Immune-checkpoint blockades (ICBs) are now used in early-stage diseases like triple-negative breast cancer (TNBC). While effective, they can cause severe toxicities. We report the first case of life-threatening immune thrombocytopenia (ITP) induced by pembrolizumab during neoadjuvant chemo-immunotherapy for early TNBC. A 42-year-old woman with early-stage TNBC developed grade 4 thrombocytopenia, diagnosed as ITP, after 107 days of pembrolizumab treatment. She required intensive care unit (ICU) admission and high-dose steroids, and intravenous immunoglobulin therapy, leading to a rapid recovery. ITP is a rare but potentially fatal complication of immunotherapy, with an incidence of less than 1% and a mortality rate of up to 20% in affected patients. Immediate recognition and steroid therapy are critical, as platelet transfusion is usually ineffective. Diagnosis is often delayed due to its similarity to chemotherapy-induced marrow toxicity. Immunotherapy-induced ITP generally contraindicates further use of the treatment. ITP, although uncommon, is a serious complication of immunotherapy requiring immediate intervention. The growing use of immunotherapy necessitates increased awareness of its potential toxicities among healthcare providers.

Ovarian cancer, ranking fifth in cancer mortality, presents a significant therapeutic challenge. The immunomodulatory functions of CD38in epithelial ovarian cancer (EOC) and its influence on the tumor microenvironment (TME) remain poorly understood.

Public datasets, RT-qPCR and immunohistochemistry (IHC) were used to analyze CD38 expression and clinicopathological features in EOC. Gene manipulation techniques were employed to elucidate its functions, while integrated IHC and bioinformatics were conducted to assess its involvement in immune/stromal infiltration. Immune-related functions of CD38 were explored using GO, KEGG analysis and TIP database. TIDE algorithm was employed to predict the correlation between CD38 and immune checkpoint blocking responsiveness. CD38 inhibitor efficacy was evaluated in an EOC mouse model, with flow cytometry monitoring cellular changes. The involvement of CD38 in the PI3K-AKT and IL-6 signaling pathways was evaluated using RT-qPCR, western blot, and publicly datasets.

CD38 is significantly upregulated in EOC, influencing the cell proliferation and metastasis. It regulates the PI3K-AKT and IL-6 signaling pathways, thereby increasing tumor malignancy. CD38 is also upregulated in immune and stromal cells, affecting TME remodeling by facilitating immune cell and CAF infiltration, impeding T cell recognition of tumor cells, and enhancing CAF-tumor cell communication. Additionally, CD38 correlates with multiple immune checkpoint molecules. Notably, CD38 inhibitor therapy inhibited effectively EOC progression and modulates immune responses.

Elevated CD38 expression is associated with EOC progression, TME remodeling, and immune response modulation. Thus, CD38 could be a promising target for ovarian cancer immunotherapy.

Tumor-stroma ratio (TSR), tumor budding (TB), and tumor-infiltrating lymphocytes (TILs) are prognostic markers in some cancers but with unknown significance in vulvar squamous cell carcinoma (VSCC). This pilot study primarily aimed to develop a digital method for evaluating TSR, TB and TILs in VSCC and secondarily to investigate variation in these factors by p16 status. An independent training set stained with CD3/cytokeratin and CD8/cytokeratin was used to develop a deep learning-based Application Protocol Package (APP) segmenting tissue into background, epithelium, or stroma. TSR was defined as percentage of tumor epithelium relative to total tumor area, and tumor buds were defined as clusters of 1-4 tumor cells. A second APP quantified CD3+ and CD8+ lymphocytes in the intraepithelial and stromal compartments, respectively. The digital algorithms were applied to the study cohort of 41 VSCC cases, achieving satisfactory performance without manual corrections. TSR ranged between 33 and 91% with median of 64%, and median number of buds was 4 (range: 0-48) buds/mm2. Median density and range of CD3+ lymphocytes were 222 (13-2320) cells/mm2 in the intraepithelial and 1978 (397-6683) cells/mm2 in the stromal compartment, respectively. CD8+ lymphocyte counts were lower. There was a tendency towards lower TSR and higher number of buds in p16-negative compared with p16-positive VSCC. Finally, automated measures were compared with manual evaluations showing high concordance. The developed automated method provided precise and objective measurements of TSR, TB and TILs. The algorithms should be validated in a larger cohort and correlated with clinicopathological characteristics and prognosis to determine their clinical relevance.

Hormone receptor (HR) status may be unstable during breast cancer (BC) progression, and changes occur in approximately 20-30% of BC patients at the time of recurrence. The biologic tumor switch from HR+ to HR- status is associated with worse clinical outcomes and warrants alternative management. We aimed to characterize clinical and pathologic features of a subset of ER+/HER2- breast cancer patients who converted to triple negative phenotype upon recurrence, and investigate the molecular alterations associated with HR loss during BC progression.

We retrospectively identified 112 patients who had primary ER+/HER2- breast cancer and developed local or distant recurrence through our institutional database. Patients were divided into two cohorts based on receptor profile of recurrent tumor: discordant TNBC (n = 20) and concordant ER+/HER2- tumors. The following variables were collected: tumor histology, grade, pT, pN, ER, PR, HER2 expression in primary and recurrent tumors, molecular profiling, and adjuvant treatment history.

The average time for HR+ tumors to recur as TNBC was 148 months. The two cohorts showed similar clinicopathologic characteristics, including patient's age at diagnosis, tumor type, grade, stage, ER expression, and treatment history before tumor recurrence. PTEN inactivating mutations were more frequently identified in the discordant TNBC (6/20, 30%) compared to the concordant ER+/HER2- tumors (6/92, 5.5%) (p = 0.007).

Increased signaling via the PI3K/AKT/PTEN pathway may be a mechanism for the transition to hormone independence in recurrent diseases.

In women with high-grade serous ovarian cancer (HGSOC), a CT-based radiomic prognostic vector (RPV) predicted stromal phenotype and survival after primary surgery. The study's purpose was to fully externally validate RPV and its biological correlate.

In this retrospective study, ovarian masses on CT scans of HGSOC patients, who underwent primary cytoreductive surgery in an ESGO-certified Center between 2002 and 2017, were segmented for external RPV score calculation and then correlated with overall survival (OS) and progression-free survival (PFS). A subset of tissue samples subjected to fibronectin immunohistochemistry were evaluated by a gynaeco-pathologist for stromal content. Kaplan-Meier log-rank test and a Cox proportional hazards model were used for outcome analysis.

Among 340 women with HGSOC, 244 ovarian lesions were available for segmentation in 198 women (mean age 59.8 years, range 34-92). Median OS was 48.69 months (IQR: 27.0-102.5) and PFS was 19.3 months (IQR: 13-32.2). Using multivariate Cox analysis, poor OS was associated with RPV-high (HR 3.17; 95% CI: 1.32-7.60; p = 0.0099), post-operative residual disease (HR 2.04; 95% CI: 1.30-3.20; p = 0.0020), and FIGO stage III/IV (HR 1.79; 95% CI: 1.11-2.86; p = 0.016). Age did not influence OS. RPV-high tissue had higher stromal content based on fibronectin expression (mean 48.9%, SD 10.5%) compared to RPV-low cases (mean 14.9%, SD 10.5%, p < 0.0001). RPV score was not significantly associated with PFS.

Patients with HGSOC and RPV-high ovarian mass on pre-operative CT had significantly worse OS following primary surgery and a higher stromal content compared to RPV-low masses, externally validating the RPV and its biological interpretation.

Question Can the performance of a previously described RPV in women with HGSOC be replicated when licenced to an external institution? Findings External validation of RPV among 244 ovarian lesions demonstrated that, on multivariate analysis, OS was associated with RPV, stage, and postoperative residual disease, replicating previous findings. Clinical relevance External validation of a radiomic tool is an essential step in translation to clinical applicability and provides the basis for prospective validation. In clinical practice, this RPV may allow more personalized decision-making for women with ovarian cancer being considered for extensive cytoreductive surgery.

To determine the value of radiomics data extraction from baseline 18F FDG PET/CT in the prediction of tumor-infiltrating lymphocytes (TILs) among patients with primary breast cancer (BC).We retrospectively evaluated 74 patients who underwent baseline 18F FDG PET/CT scans for BC evaluation between October 2020 and April 2022. Radiomics data extraction resulted in a total of 131 radiomic features from primary tumors. TILs status was defined based on histological analyses of surgical specimens and patients were categorized as having low TILs or moderate & high TILs. The relationships between TILs groups and tumor features, patient characteristics and molecular subtypes were examined. Features with a correlation coefficient of less than 0.6 were analyzed by logistic regression to create a predictive model. The diagnostic performance of the model was calculated via receiver operating characteristics (ROC) analysis.Menopausal status, histological grade, nuclear grade, and four radiomics features demonstrated significant differences between the two TILs groups. Multivariable logistic regression revealed that nuclear grade and three radiomics features (Morphological COMShift, GLCM Correlation, and GLSZM Small Zone Emphasis) were independently associated with TIL grouping. The diagnostic performance analysis of the model showed an AUC of 0.864 (95% CI: 0.776-0.953; p < 0.001). The sensitivity, specificity, PPV, NPV and accuracy values of the model were 69.6%, 82.4%, 64%, 85.7% and 78.4%, respectivelyThe pathological TIL scores of BC patients can be predicted by using radiomics feature extraction from baseline 18F FDG PET/CT scans.

To correlate between immunohistochemical expression of tumor-infiltrating lymphocytes (TILs), tumor-associated macrophages (TAMs), and natural killer (NK) cells with the AJCC 8th edition TNM staging system and other disease-modifying clinico-pathological variables.

The representative histology sections of tumor invasive margin (IM) and tumor core (TC) were selected according to the International Immuno-Oncology Biomarker Working Group and were subjected to immunohistochemistry with antibodies for TILs (CD3, CD8, FOXP3), NK Cells (CD57), TAMs (CD68, CD163) and pan-leukocyte marker (CD45). Histo-immuno-density-intensity (HIDI) scoring was calculated as a product of the proportion and intensity of staining. Ordinal-ordinal and continuous-ordinal variables were correlated using Kendall's tau-b (τb), and binary-ordinal variables were correlated using Rank-Biserial (rrb) statistics.

A total of 111 patients were included in the study. None of the clinical and pathological parameters showed a strong correlation with any of the immune infiltrates including TNM staging.

We hypothesize an independent activity of tumor immunology in the disease prognosis.

CTRI/2020/07/026335.

An 80-year-old woman with a left breast mass was referred to our department. Mammography showed an oval mass, 2.5cm in size, with circumscribed margins in her left breast. Ultrasound showed an oval tumor with circumscribed margins, heterogenous internal echoes including numerous punctate hyperechoic foci, and posterior echo enhancement. Magnetic resonance imaging (MRI) of the tumor showed low and high signal intensity on T1-weighted images and on fat-suppressed T2-weighted images, respectively. Kinetic curve assessment of the tumor showed a fast and plateau pattern. After the pathological confirmation of malignant cells, the patient underwent mastectomy and sentinel node biopsy. Postoperative pathological study showed that atypical cells formed irregularly arranged papillary nests and grew in a medullary fashion accompanied by massive lymphocyte infiltration, leading to the diagnosis of invasive ductal carcinoma with medullary features (IDCMF). Immunostaining showed that the tumor had a triple negative phenotype and a high Ki-67 labelling index of 52%. In conclusion, breast diagnostic physicians should note that IDCsMF show a fast and plateau enhancement pattern on MRI kinetic curve assessment. Furthermore, the presence of punctate hyperechoic foci in the tumor can be useful in distinguishing IDCsMF from medullary breast carcinomas.

The breast cancer (BC)-related mortality is higher and the immunity is altered in women living with HIV (WLWH) compared to HIV-negative women. Therefore, tumor samples of 296 black BC patients from South Africa and Namibia with known age, HIV status, tumor stage, hormone receptor and HER2 status and overall survival (OS) are analyzed for components of the tumor microenvironment (TME). WLWH (n = 117), either with suppressed viral activity (HR = 1.25) or with immune suppression (HR = 2.04), have a shorter OS. HIV status is associated with increased numbers of CD8+ T cells in the TME compared to HIV-negative patients; no correlation is found with CD4+ T cell numbers in the blood. Moreover, an increased expression of CD276/B7-H3 and a more pronounced IFN-γ signaling in the tumors are found in WLWH, independent of age, stage, and BC subtypes. In conclusion, altered T cell composition and CD276 expression in WLWH may contribute to inferior survival and can be used for targeted treatment.

Estrogen receptor (ER) expression is critical in breast cancer treatment. While low ER (1-9%) resembles triple-negative cancer with chemotherapy efficacy, the significance of "intermediate expression" (≥ 10%) and the therapeutic efficacy remain unclear. This study explores the differences in staining patterns and molecular characteristics of ER-low to intermediate expression to guide treatment.

A total of 104 breast cancer patients treated between January 2008 and July 2024 with an Allred Proportion Score (PS) of 2-4 were included. PS2 (n = 21) was classified as ER-low, while PS3 (n = 26) and PS4 (n = 57) as ER-intermediate (ER-int). ER-int was further divided by ER staining pattern: "Island" (heterogeneous) and "Scatter," (uniform) subgroups. The prognosis, clinical factors, and gene expression profiles (n = 11) were analyzed.

The Island subgroup was associated with poorest prognosis (p = 0.0116), particularly among the patients treated with endocrine-only treatment patients (p < 0.0001). Elevated tumor-infiltrating lymphocyte (TIL) levels correlated with worse prognosis in endocrine-only treatment patients (p < 0.0043), with TIL levels highest in ER-low, followed by Island and Scatter subgroups. Island tumors were enriched in CD36, GZMB, and type I interferon genes; additionally, 23 "ISLAND" genes showed significant prognostic differences in the TCGA BRCA ER-int (10-69%) cohort.

This study emphasizes the importance of recognizing heterogeneity within the ER-int subtype. Identifying distinct ER staining patterns and prognostic significance of TILs and transcriptome in ER-int tumors suggests the need for individualized treatment strategies for Island subtype.

Immune checkpoint inhibitors (ICIs) are shown to improve cancer treatment effectiveness by boosting the immune system of the patient. Nevertheless, the unique and highly suppressive TME poses a significant challenge, causing heterogeneity of response or resistance in a considerable number of patients. This review focuses on the evasive attributes of the TME. Immune evasion mechanism in TME include immunosuppressive cells, cytokine and chemokine signaling, metabolic alterations and overexpression of immune checkpoint molecules such as PD-1, CTLA-4, LAG-3, TIM-3, TIGIT, BTLA and their interactions within the TME. In addition, this review focuses on the overcoming resistance by targeting immunosuppressive cells, normalizing tumor blood vessels, blocking two or three checkpoints simultaneously, combining vaccines, oncolytic viruses and metabolic inhibitors with ICIs or other therapies. This review also focuses on the necessity of finding predictive markers for the stratification of patients and to check response of ICIs treatment. It remains to be made certain by new research and intelligent innovations how these discoveries of the TME and its interplay facilitate ICI treatment and change the face of cancer treatment.

Breast cancer remains a formidable global health challenge, with tumor-infiltrating lymphocytes (TILs) serving as pivotal biomarkers associated with disease progression, therapeutic response, and survival. While research typically focused on stromal TILs (sTILs), we hypothesize that intratumoral TILs (iTILs), which are in direct contact with tumor cells, have a more profound role in the immune-tumor interactions. In light of this, we have developed an iTIL-centric model for breast cancer patient stratification and prognostic prediction.

We sourced RNA-seq data and clinical profiles of breast cancer patients from The Cancer Genome Atlas (TCGA) and the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) to form our training dataset. Testing datasets, including GSE20685, GSE42568, GSE48390, and GSE88770, were retrieved from Gene Expression Omnibus (GEO). Employing consensus clustering and Weighted Correlation Network Analysis (WGCNA), we identified iTIL-associated hub genes. Our iTIL-centric signature was developed using a machine learning framework integrating 101 algorithms, validated across independent testing sets. Kaplan-Meier analysis and a nomogram model were utilized to evaluate the prognostic accuracy and clinical correlation of our model. GO and KEGG analyses elucidated the biological processes and pathways related to the iTIL signature. The immune profiling provided a comprehensive assessment of the immunological landscape. Moreover, potential drugs for high-risk patients were identified using CTRP v.2.0 and PRISM databases.

Our study constructed a pioneering prognostic model based on iTIL-centric signature via a machine learning framework that evaluated 101 algorithm combinations. This model revealed significant differences in the immune landscape among stratified patient cohorts, and demonstrated robust predictive capabilities across multiple datasets. The model showed excellent predictive performance with area under the curve (AUC) values of 0.940, 0.959, and 0.973 for 3-, 5-, and 10-year survival predictions, respectively. Additionally, it was identified as a significant risk factor for overall survival (OS) in the univariate analysis, with a hazard ratio (HR) > 1 and a p-value < 0.001.

Our prognostic model, founded on machining learning algorithms and anchored by an iTIL-centric signature, stands out as an invaluable tool for breast cancer patients, offering advanced prognostic insights and facilitating the development of personalized therapeutic strategies.

Stromal tumor-infiltrating lymphocytes (sTILs) have significant prognostic value for breast cancer patients, but its accurate assessment can be very challenging. We comprehensively studied the pitfalls faced by pathologists with different levels of professional experience, and explored clinical applicability of reference cards (RCs)- and artificial intelligence (AI)-assisted methods in assessing sTILs.

Three rounds of ring studies (RSs) involving 12 pathologists from four hospitals were conducted. AI algorithms based on the field of view (FOV) and whole section were proposed to create RCs and to compute whole-slide image interpretations, respectively. Stromal regions identified and the associated sTIL scores by the AI method were provided to the pathologists as references. Fifty cases of surgical resections were used for interobserver concordance analysis in RS1. A total of 200 FOVs with challenge factors were assessed in RS2 for accuracy of the RC-assisted and AI-assisted methods, while 167 cases were used to validate their clinical performance in RS3.

With the assistance of RCs, the intraclass correlation coefficient (ICC) in RS1 increased significantly to 0.834 [95% confidence interval (CI) 0.772-0.889]. The largest enhancement in ICC, from moderate (ICC: 0.592; 95% CI 0.499-0.677) to good (ICC: 0.808; 95% CI 0.746-0.857) was observed for heterogeneity. Accuracy evaluation showed significant grade improvement for heterogeneity and stromal factor FOVs among senior, intermediate, and junior groups. The ICC of heterogeneity and stromal factor analysis by the AI-assisted method achieved a level comparable to that of the senior group with RC assistance. The area under the receiver operating characteristic (ROC) curve, denoted as AUC, for AI-assisted sTIL scores in predicting pathological complete response after neoadjuvant therapy was 0.937, which was superior to visual assessment with an AUC of 0.775.

RC- and AI-assisted technology can reduce the uncertainty of interpretation caused by heterogeneous distribution.

Breast cancer diagnosed during pregnancy (PrBC) is a rare occurrence but may become more prevalent as women nowadays tend to postpone childbearing until later in life. Further understanding of how pregnancy affects the tumor microenvironment (TME) is essential. We constructed Tissue Microarrays (TMA) of tumor specimens from 126 pregnant breast cancer (BC) patients and examined standard BC markers such as ER, PR, Ki67, HER2, tumor infiltrating lymphocytes (TILs), and immunomarkers HLA class I, HLA-G, PD-L1, TIGIT and Nectin-4. Subsequently, we compared our findings with those from a matched non-pregnant cohort of young BC patients. Pregnant BC patients were younger, had significantly higher proliferation rates and a higher expression of Nectin-4. Higher pregnancy related estrogen levels may boost proliferation und Nectin-4 overexpression, promoting BC progression. No further evidence supporting impaired maternal anti-tumor response in BC was observed in this study.

In the phase II NIMBUS trial, patients with human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC) and high tumor mutational burden (TMB ≥ 9 mut/Mb) received nivolumab (3 mg/kg biweekly) and low-dose ipilimumab (1 mg/kg every 6 weeks) for 2 years or until progression. The primary endpoint was objective response rate (ORR) per RECIST 1.1 criteria. Among 30 patients enrolled, the median TMB was 10.9 mut/Mb (range: 9-110) and the confirmed objective response rate was 20%. Secondary endpoints included progression-free survival, overall survival, clinical benefit rate, and safety and tolerability, including immune-related adverse events (irAEs). A prespecified correlative outcome was to evaluate the ORR in patients with a TMB ≥ 14 mut/Mb. Patients with TMB ≥ 14 mut/Mb (n = 6) experienced higher response rates (60% vs 12%; p = 0.041) and showed a trend towards improved progression-free survival and overall survival compared to patients with TMB < 14 mut/Mb. Exploratory genomic analyses suggested that ESR1 and PTEN mutations may be associated with poor response, while clinical benefit was associated with a decrease or no change in tumor fraction by serial circulating tumor DNA during treatment. Stool microbiome analysis revealed that baseline blood TMB, PD-L1 positivity, and immune-related diarrhea are associated with distinct taxonomic profiles. In summary, some patients with hypermutated HER2-negative MBC experience extended clinical benefit with a dual immunotherapy regimen; a higher TMB, and additional genomic and microbiome biomarkers may optimize patient selection for therapy with nivolumab plus low-dose ipilimumab. (Funded by Bristol Myers Squibb; ClinicalTrials.gov identifier, NCT03789110).

The RANK pathway has been extensively investigated for its role in bone resorption; however, its significance extends beyond bone metabolism. Preclinical models suggest that inhibition of RANK signaling can prevent mammary tumor development by reducing proliferation and tumor cell survival. Additionally, both preclinical and clinical data support the ability of RANK pathway inhibitors to enhance the anti-tumor immune response.

D-BIOMARK is a prospective, randomized window-of-opportunity clinical trial assessing the biological effects of denosumab, a monoclonal antibody against RANKL, in patients with HER2-negative early breast cancer. The study aims to assess denosumab's impact on breast tumor cell proliferation, apoptosis, and its potential to influence the tumor immune microenvironment. A total of 60 patients were enrolled and randomized 2:1 to receive two doses of single agent denosumab (120 mg one week apart) before surgery or to the control arm (no treatment). Fifty-eight patients were evaluated, 27 pre-menopausal and 31 post-menopausal women, 48 with luminal tumors and 10 with triple negative breast cancer. Paired tumor samples were collected to compare baseline (core biopsy) and surgical (surgical specimen) time points, as well as serum samples at both time points.

Denosumab demonstrated its ability to reduce serum free RANKL levels (experimental p < 0.001, control p = 0.270). However, a reduction in tumor cell proliferation or cell survival was not observed. A denosumab-driven increase in tumor infiltrating lymphocytes (TILs) was observed (experimental p = 0.001, control p = 0.060), particularly in the luminal B-like population (experimental p = 0.012, control p = 0.070) and a similar trend in the TNBC group (experimental p = 0.079, control p = 0.237). Denosumab led to increased TILs in both pre-menopausal (experimental p = 0.048, control p = 0.639) and post-menopausal (experimental p = 0.041, control p = 0.062) women with luminal tumors. RANK protein expression in tumor and stroma was associated with markers of tumor aggressiveness but an increase in TILs was observed in the experimental arm, irrespectively of RANK and RANKL expression in tumor or stromal cells.

The D-BIOMARK trial suggests a potential role for denosumab as an immune-enhancing agent in early HER2-negative breast cancer. Although preoperative denosumab did not reduce tumor proliferation or increased apoptosis, it led to an increase in TILs, particularly in luminal B-like tumors. These findings underscore the importance of further investigation into the multifaceted aspects of the RANK pathway. Trial registration EudraCT number: 2016-002678-11 registered on June 15, 2018.

gov identifier: NCT03691311, retrospectively registered on September 04, 2018.

Treatment of early breast cancer is currently experiencing a rapid evolution because of important insight into tumor subtypes and continuous development and improvement of novel therapeutics. Historically considered non-immunogenic, breast cancer has seen a paradigm shift with increased understanding of immune microenvironment, which have revealed extensive heterogeneity in tumor-associated inflammation. Notably, the more aggressive breast cancer subtypes, including triple-negative and HER2-positive, have exhibited favorable responses to combined chemo-immunotherapy protocols. Neoadjuvant therapy has emerged as the standard of care for these tumors, with pathological complete response used as a surrogate endpoint for long-term clinical outcomes and coincidently expediting new drug approval. The neoadjuvant setting affords a unique opportunity for in vivo treatment response evaluation and effects on the tumor microenvironment. In this review, the predictive and prognostic value of the tumor immune microenvironment before, during, and after treatment across various therapeutic regimens, tailored to distinct breast cancer subtypes, is carefully examined.

Breast cancer (BC) is a leading cause of death among women, with approximately 30% HER2-positive (HER2+). Although HER2-targeted therapies have improved outcomes for patients with HER2+ metastatic breast cancer (mBC), clinical challenges and prognostic variability remain. Tumor-infiltrating lymphocytes (TILs) have emerged as prognostic and predictive biomarkers in various tumors, including BC, but their role in HER2+ mBC is poorly understood. This multicentric retrospective cohort study evaluated the prognostic significance of TILs in 110 patients with HER2+ mBC treated with pertuzumab, trastuzumab, and taxane-based chemotherapy at two Italian institutes from June 2013 to May 2024. TILs were assessed on metastatic or primary tumor samples. High TILs levels (>5%) were independently associated with longer PFS and OS. TILs levels were higher in primary tumours than in metastases (p = 0.009), with significant variation by metastatic site. These findings underscore the potential of TILs as prognostic biomarkers in HER2+ mBC, necessitating further prospective studies.

The amplification or overexpression of human epidermal growth factor receptor 2 (HER2) defines a breast cancer subtype, which benefits from neoadjuvant HER2-targeted therapy. However, at least 40% of patients respond poorly or do not respond to treatment. We analyzed the main genomic alterations of 64 HER2+ patients by next-generation sequencing to identify new predictors of response and correlate them with clinicopathological parameters. We also compared the genomic alterations between primary and residual tumors after neoadjuvant treatment. The TP53 gene was the most frequently mutated gene, and in combination with ERBB2 overexpression, the 2 were predictive of residual cancer burden (P = .001). Furthermore, the combination of their immunohistochemical counterpart (p53 mutant and score 3+ for HER2) can predict complete pathological response and the grade of response (P = .038 and P = .031, respectively). Therefore, p53 could be included in the initial panel of breast cancer biomarkers to help therapeutic decision-making in HER2+ cases.

The intricateness of tumor immune microenvironment types (TIMTs) complicates identifying responders to immune checkpoint inhibitors (ICIs). Our purpose was to explore the metabolic characteristics of TIMTs in breast cancer using 18F-fluorodeoxyglucose (FDG) PET/CT and to establish radiomics-based predictive models for TIMTs.

Consecutive 207 breast cancer patients (211 primary lesions), who underwent 18F-FDG PET/CT examination from Sep 2022 to Aug 2024 in our hospital, were retrospectively reviewed. The programmed death-ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) were evaluated for TIMTs: TMIT-I (PD-L1-, TILs-), TMIT-II (PD-L1+, TILs+), TMIT-III (PD-L1-, TILs+), and TMIT-IV (PD-L1+, TILs-). The relationship between metabolic parameters (such as maximum standardized uptake value (SUVmax) and tumor-to-liver SUV ratio (TLR)) and TIMTs was analyzed. Then composite predictive models based on radiomics were further developed.

TIMT-II represented the highest proportion in HER2+ (14/22, 64%) and triple-negative (17/27, 63%) breast cancer. Most metabolic parameters (such as SUVmax and TLR) exhibited significant differences in TIMT-II vs. -I or TIMT-II vs. -III (P < 0.05). TLR (P = 0.03; OR: 1.1) and Nottingham grade (P = 0.006; OR: 3.1) were independent impact factors of TIMT-II. We further developed a composite model that integrated radiomics, metabolic parameter, and clinicopathological data, which demonstrated promising predictive efficacy for TIMT-II (AUC testing set = 0.86).

Metabolic differences existed among different TIMTs, with TIMT-II exhibiting markedly elevated metabolic characteristics. The composite model based on radiomics demonstrated high predictive efficacy for TIMT-II and has the potential to screen ICIs responders.

The SWI/SNF complex is an important chromatin remodeling complex that has been reported in various tumors. To date, there have been no reports on the subunits of this complex in primary small bowel adenocarcinoma (PSBA).

Hematoxylin & Eosin (H&E) staining slides were reviewed, and the expression of MMR protein, BRM (SMARCA2), BRG1 (SMARCA4), INI1 (SMARCB1), and ARID1A proteins was detected. Molecular genetic testing was performed utilizing the amplification-refractory mutation system (ARMS) and high-throughput sequencing technology.

In this cohort of 58 cases, there was a trend toward a female predominance in ARID1A loss (P = 0.084), and BRM (SMARCA2) loss was associated with lymphatic invasion (P = 0.043). A significant positive correlation was observed between ARID1A loss and dMMR (P = 0.021), and BRG1 (SMARCA4) loss was more prevalent in poorly differentiated PSBA (P = 0.023). ARID1A loss was positively correlated with PIK3CA gene mutation (r = 0.551, P < 0.001), and loss of MMR protein expression was also positively correlated with PIK3CA gene mutation (r = 0.354, P = 0.006). Additionally, BRM (SMARCA2) loss showed a significant positive correlation with NRAS gene mutation (r = 0.293, P = 0.025) and a significant negative correlation with KRAS gene mutation (r = -0.281, P = 0.033). Univariate analysis indicated a trend toward poor prognosis with BRM (SMARCA2) loss (P = 0.097).

This study represents the initial description of loss of the SWI/SNF complex expression in PSBA, which is rare and primarily originates in the jejunum and ileum. Further investigations are warranted to elucidate potential targets of PIK3CA inhibitors for dMMR PSBA and ARID1A loss of expression in PSBA.

This study evaluates the reproducibility of the IRSN-23 model, which classifies patients into highly chemotherapy-sensitive (Gp-R) or less-sensitive (Gp-NR) groups based on immune-related gene expression using DNA microarray analysis, and its impact on breast cancer subtype classification.

Tumor tissues from 146 breast cancer patients receiving neoadjuvant chemotherapy (paclitaxel-FEC) ± trastuzumab at Osaka University Hospital (OUH) were used to classify patients into Gp-R or Gp-NR using IRSN-23. The ability to predict a pathological complete response (pCR) was assessed and the results were validated with independent public datasets (N = 1282).

In the OUH dataset, the pCR rate was significantly higher in the Gp-R group than in the Gp-NR group without trastuzumab (29 versus 1%, P = 1.70E-5). In all validation sets without anti-HER2 therapy, the pCR rate in the Gp-R group was significantly higher than that in the Gp-NR group. The pooled analysis of the validation set showed higher pCR rates in the Gp-R group than in the Gp-NR group, both without (N = 1103, 40 versus 12%, P = 2.02E-26) and with (N = 304, 49 versus 35%, P = 0.017) anti-HER2 therapy. Collaboration analyses of IRSN-23 and Oncotype Dx or PAM50 could identify highly chemotherapy-sensitive groups and refine breast cancer subtype classification based on the tumor microenvironment (offensive factor-PAM50 and defensive factor-IRSN-23), and the immune subtype was correlated with a better prognosis after NAC.

This study offers new validation analyses of IRSN-23 in predicting chemotherapy efficacy, showing high reproducibility. The findings indicate the clinical value of using IRSN-23 for refining breast cancer subtype classification, with implications for personalized treatment strategies and improved patient outcomes.

B cells play diverse roles in different pathological circumstances, such as neoplastic diseases, autoimmune disorders, and neurological maladies. B cells, which are essential elements of the adaptive immune system, demonstrate exceptional functional variety, including the generation of antibodies, the presentation of antigens, and the secretion of cytokines. Within the field of oncology, B cells display a multifaceted nature in the tumor microenvironment, simultaneously manifesting both tumor-promoting and tumor-suppressing characteristics. Studies have found that the existence of tertiary lymphoid structures, which consist of B cells, is linked to better survival rates in different types of cancers. This article examines the involvement of B cells in different types of malignancies, emphasizing their importance in the development of the diseases and their potential as biomarkers. Additionally, the review also examines the crucial role of B cells in autoimmune illnesses and their potential as targets for therapy. The article also analyses the role of B cells in immunization and exploring their potential uses in cancer immunotherapy. This analysis highlights the intricate and occasionally contradictory roles of B cells, underlining the necessity for additional research to clarify their varied actions in various illness scenarios.

Assessment of the tumor-immune microenvironment can be used as a prognostic tool for improved survival and as a predictive biomarker for treatment benefit, particularly from immune-modulating treatments including cytotoxic chemotherapy. Using digital spatial profiling (DSP), we studied the tumor-immune microenvironment of 522 breast cancer cases by quantifying 35 immune biomarkers on tissue microarrays from the MA.5 phase III clinical trial. In this trial, node-positive breast cancer patients were randomized to receive either non-anthracycline chemotherapy (cyclophosphamide, methotrexate, 5'-fluorouracil [CMF]) or anthracycline-containing cytotoxic chemotherapy (CEF). Donor block hematoxylin and eosin (H&E)-stained sections were scored for the level of stromal tumor-infiltrating lymphocytes (sTILs), according to the international guidelines. We hypothesized that patients with higher levels of tumor-immune infiltration, assessed by either DSP or H&E staining, would benefit from CEF (relative to CMF) more than patients with lower immune infiltration. Unsupervised hierarchical clustering of digitally scored biomarkers revealed 2 patient clusters: immune infiltrated versus ignored. Following a prespecified statistical plan crafted to meet REMARK (REporting recommendations for tumor MARKer prognostic studies) guidelines, we found that the DSP-derived Immune Cluster assignment did not predict an improved 10-year relapse-free survival for patients receiving CEF compared with CMF. However, a secondary hypothesis revealed a significant predictive value for H&E sTILs assessed on full-faced sections for CEF benefit over CMF in the entire cohort and the human epidermal growth factor receptor 2-enriched subset. As exploratory analyses, supervised clustering of DSP-scored biomarkers suggested that low levels of T-cell immunoglobulin and mucin domain 3 TIM-3 and high levels of human leukocyte antigen HLA-DR and programmed cell death protein ligand PD-L-1 are associated with sensitivity to CEF. Although novel high-plex techniques provide a detailed insight into the tumor microenvironment, conventional H&E staining remains a powerful tool that can be applied to full-faced sections to assess the value of the immune microenvironment, particularly sTILs, in predicting benefits from immunogenic chemotherapies.

Oral Cancer is one of the most prevalent malignant tumors of the head and neck. The three primary clinical treatments available till now for oral cancer are chemotherapy, radiation, and surgery. The goal of this review was to outline the basic principles of immunotherapy along with various immunotherapeutic agents on Oral Squamous Cell Carcinoma.

A comprehensive search in PubMed, Scopus, and Google Scholar was performed using relevant keywords. All the articles, both English as well as non-English were included also with inclusion data from high-incidence countries (South-east Asia) and the compilation was ten done after getting the data reviewed from two pathologists who were blinded to the data.

All the data has been compiled and the various sections in the manuscript provides an insight into the current trends in immunotherapy.

Advanced research studies are needed to counteract the hurdles associated with immunotherapy so that a greater proportion of patients can be treated.

One of the more recent developments that is promising is immunotherapy, which can be quite beneficial when used as a monotherapy or an adjuvant treatment. This more recent treatment approach could serve as the fourth pillar in cancer care, alongside radiation, chemotherapy, and surgery. Because immunotherapy relies on the patient's immunological environment, careful patient selection is essential to its effectiveness.

The immune cell component of the tumor microenvironment is an important modulator of tumor progression. In patients with breast cancer, tumor-infiltrating lymphocytes (TILs) and tertiary lymphoid structures (TLS) represent core aspects of antitumor immunity, both increasingly recognized for clinical relevance. In this study, we evaluated immune-related histology features using whole-slide hematoxylin and eosin (H&E) images of The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) data set (n = 1035) and analyzed these distinct features relative to gene expression, PAM50 subtypes, and patient survival. H&E images were evaluated for TILs, plasma cells (PCs), high-endothelial venule-associated lymphoid aggregates (HALA), and mature TLS. For HALA and TLS, location relative to the tumor (nontumor, peritumor, and intratumor) was determined. HER2-enriched (HER2E) and basal-like breast tumors exhibited the highest mean TILs and the presence of PCs. HALA were present in 35.1% of cases and TLS in 6.5% of cases, also predominantly in HER2E and basal-like tumors. We derived gene expression signatures for 10 histologically defined immune features and tested their clinical significance using transcriptomic and survival data from the Sweden Cancerome Analysis Network - Breast (SCAN-B) cohort. Signatures related to TILs, PCs, HALA/TLS, TLS, and specifically intratumor HALA and TLS were associated with better survival in HER2E and basal-like tumors. Peritumor HALA/TLS and nontumor signatures were nonsignificant or associated with worse outcomes. Furthermore, we compared the immune microenvironment of high-TIL (TILs > 10%) tumors from TCGA-BRCA by PAM50 subtype through supervised analyses of 200+ immune gene expression signatures, and unique immune features were identified for each subtype. In high-TIL luminal tumors, enriched immune signatures had little relation to prognosis. High-TIL HER2E and basal-like tumors had distinct immune signatures linked to improved survival, related to B and T cells, respectively. Overall, PAM50 subtypes of breast cancer exhibit distinct immune microenvironments, both histologically and molecularly. These differences in immune properties should be considered when developing precise treatment strategies to achieve optimal therapeutic efficacy for patients.

Triple-negative breast cancer (TNBC) continues to present a therapeutic challenge due to the fact that by definition, these cancer cells lack the expression of targetable receptors. Current treatment options include cytotoxic chemotherapy, antibody-drug conjugates (ADC), and the PD-1 checkpoint inhibitor, pembrolizumab. Due to high rates of recurrence, current guidelines for early-stage TNBC recommend either multi-agent chemotherapy or chemo-immunotherapy in all patients other than those with node-negative tumors < 0.5 cm. This approach can lead to significant long-term effects for TNBC survivors, driving a growing interest in de-escalating therapy where appropriate. Tumor infiltrating lymphocytes (TILs) represent a promising prognostic and predictive biomarker for TNBC. These diverse immune cells are present in the tumor microenvironment and within the tumor itself, and multiple retrospective studies have demonstrated that a higher number of TILs in early-stage TNBC portends a favorable prognosis. Research has also explored the potential of TIL scores to predict the response to immunotherapy. However, several barriers to the widespread use of TILs in clinical practice remain, including logistical and technical challenges with the scoring of TILs and lack of prospective trials to validate the trends seen in retrospective studies. This review will present the current understanding of the role of TILs in TNBC and discuss the future directions of TIL research.

Soft tissue sarcomas (STSs) are conventionally viewed as poorly immunogenic tumors; however, some human STSs have recently been reported to elicit an immune response, thus representing potential candidates for immunotherapy. Data regarding immune cell infiltrates in canine STSs are limited and reported without tumor-type stratification. The aim of this study was to retrospectively assess tumor-infiltrating lymphocytes (TILs) in canine STSs of 5 different histotypes. Eighty-seven canine STSs were collected: 22 perivascular wall tumors (PWTs), 19 liposarcomas, 17 fibrosarcomas, 16 myxosarcomas, and 13 leiomyosarcomas. The tumors were graded and immunolabeled for CD3, CD20, and FoxP3, and slides were scanned. T-cell, B-cell, Treg, and total TIL densities were quantified with QuPath software and expressed as cells/mm2. The B/T-cells ratio and Treg/T-cell proportions were calculated. Total TIL densities were higher in PWTs and myxosarcomas (median = 225 and 303, respectively). PWTs had higher T-cell density but lower Treg proportion (median = 152 and 7.6% respectively). Myxosarcomas had higher Treg densities and B/T-cell ratios (median = 24.4 and 1.57, respectively). No association with grade was found among STSs as a group. In myxosarcomas, higher grade was significantly associated with higher total TILs, and CD20+ and FoxP3+ cell densities (p < .05). The results suggest that PWTs and myxosarcomas may represent the most immunogenic STS types. Myxosarcomas elicit a B-cell and Treg-rich immune response; PWTs stimulate a T-cell-rich and Treg-poor reaction. The immune system response may contribute to the more aggressive behavior of myxosarcomas and the more indolent course of PWTs.

In recent years, neoadjuvant chemotherapy (NACT) has become an increasingly important treatment for triple-negative breast cancer (TNBC). As the most immunogenic subtype of breast cancer, it is imperative to comprehensively study the immune microenvironment of TNBC and the effects of NACT on it. Our study aims to address this need and provide valuable insights for the development of effective postoperative adjuvant treatment strategies.

Samples were taken prior to and following NACT with docetaxel, epirubicin, and cyclophosphamide (TEC) from 71 TNBC patients who were included in this trial. We examined the clinicopathological alterations in patients before and after NACT treatment, assessed the impact of stromal tumor-infiltrating lymphocytes (sTILs) and immune biomarkers [CD8, CD4, CD3, FOXP3, CD20, CD163, programmed cell death ligand 1 (PD-L1)] on the efficacy of neoadjuvant therapy, and identified changes in NACT-induced immune subsets and specific immune biomarkers.

Our study revealed that tumor size, histological grade, Ki-67 status, and sTILs content in baseline clinical features, as well as CD3, CD4, and CD8 content before NACT, showed significant differences between pathological complete response (pCR) and non-pCR patients (P<0.05). The expression of sTILs and PD-L1 in residual lesions after NACT was found to be higher than before NACT. Univariate analysis indicated that the levels of sTILs, CD3, CD4, and CD8 immune subsets before NACT were correlated with pCR. Importantly, multivariate regression analysis demonstrated that sTILs and CD8 immune subsets before NACT served as independent predictors of TNBC neoadjuvant therapy (P<0.05), providing crucial insights into the individualized management of TNBC.

The findings of this study suggest that increasing sTILs and CD8 can significantly enhance the neoadjuvant efficacy of TNBC. Furthermore, the addition of CD3 and CD8 immune subsets can substantially improve the efficacy of TNBC neoadjuvant prediction. The detection of relevant immune markers after neoadjuvant therapy holds great promise in providing more comprehensive and accurate prognostic and therapeutic information for TNBC patients.

With the emergence of novel anti-HER2 antibody drug conjugates, patients with HER2-low breast cancer have received increased attention. Tumor-infiltrating lymphocytes (TILs) are significantly associated with survival benefits in cancers. However, their prognostic value in patients with low her2 breast cancer is unknown. Therefore, we aimed to determine the relationship between TILs and recurrence in patients with HER2-low breast cancer.

Clinicopathological data were retrospectively collected from patients with human epidermal growth factor receptor 2 (HER2) low-expression breast cancer who underwent consultations at Qingdao University Affiliated Hospital. We determined the correlation between TILs and disease-free survival (DFS) followed by the threshold value of TILs using X-tile software. Survival was assessed using Kaplan-Meier analysis, and cox regression analysis was performed for recurrence risk modeling.

Our study showed a 15% TIL level was the optimal cutoff for DFS. The low and high TILs survival curves showed significant differences in the log-rank test (p = 0.009). Cox regression analyses found that lymph node stage, histologic grading, TILs, and Ki-67 were independent variables influencing the prognosis (p < 0.05). On this basis, we developed a risk prediction model to accurately predict the 3- and 5-year disease-free survival rates of patients with HER2-low breast cancer, the model demonstrated good overall performance.

TILs are associated with recurrence in patients with breast cancer and low HER2 levels. TILs > 0.15 is a reliable indicator of DFS. For patients with low TILs (≤ 0.15), extensive follow-up is required. These findings provide a basis for targeted, individualized treatment.

The tumour microenvironment is composed of a complex cellular network involving cancer, stromal and immune cells in dynamic interactions. A large proportion of this network relies on direct physical interactions between cells, which may impact patient responses to clinical therapy. Doublets in scRNA-seq are usually excluded from analysis. However, they may represent directly interacting cells. To decipher the physical interaction landscape in relation to clinical prognosis, we inferred a physical cell-cell interaction (PCI) network from 'biological' doublets in a scRNA-seq dataset of approximately 18,000 cells, obtained from 7 treatment-naive ovarian cancer patients. Focusing on cancer-stromal PCIs, we uncovered molecular interaction networks and transcriptional landscapes that stratified patients in respect to their clinical responses to standard therapy. Good responders featured PCIs involving immune cells interacting with other cell types including cancer cells. Poor responders lacked immune cell interactions, but showed a high enrichment of cancer-stromal PCIs. To explore the molecular differences between cancer-stromal PCIs between responders and non-responders, we identified correlating gene signatures. We constructed ligand-receptor interaction networks and identified associated downstream pathways. The reconstruction of gene regulatory networks and trajectory analysis revealed distinct transcription factor (TF) clusters and gene modules that separated doublet cells by clinical outcomes. Our results indicate (i) that transcriptional changes resulting from PCIs predict the response of ovarian cancer patients to standard therapy, (ii) that immune reactivity of the host against the tumour enhances the efficacy of therapy, and (iii) that cancer-stromal cell interaction can have a dual effect either supporting or inhibiting therapy responses.

Triple-negative breast cancer (TNBC) is an aggressive subtype requiring further knowledge of biomarkers to improve targeted therapy. A major resistance mechanism involves breast cancer stem cells (BCSCs) evading the immune system. Neoadjuvant or adjuvant chemotherapy may alter BCSCs and the patients' immune response. We conducted a retrospective study including 29 early-stage TNBC patients resistant to chemotherapy diagnosed at the Catalan Institute of Oncology (Girona, Spain) in 2010-2019. We obtained 44 paired tumor samples (pre- and post-chemotherapy) from the Tumor Biobank, assessing BCSC biomarkers (CD44, CD24, and ALDH1), PD-L1, and percentages of stromal tumor-infiltrating lymphocytes (TILs). Clinicopathological characteristics were also collected. At baseline, 68% of tumors had high CD44 expression, 55% showed low CD24 expression, 9% had high ALDH1 expression, 91% were PD-L1-negative (<1%), and 64% had a low percentage of stromal TILs. PD-L1 expression significantly increased post-chemotherapy, with 50% of initially negative tumors becoming PD-L1 positive (≥1%) (p = 0.006). No significant changes were observed in BCSC markers or TILs. No association was found between baseline BCSCs and increased PD-L1 expression post-chemotherapy. At a median follow-up of 58.9 months, 48.3% of patients were alive, with non-significant favorable trends in time to progression, disease-free survival, and overall survival in the PD-L1 positivization cohort post-chemotherapy. In conclusion, high-risk early-stage TNBC tumors increased PD-L1 expression after chemotherapy, potentially affecting clinical outcomes. BCSCs remained stable and independent of the tumor immunogenicity post-chemotherapy. Further studies are needed to explore the relationship between BCSCs and the immunogenicity profile, for development of new combined therapeutic strategies.

Background/Objectives: Elevated expression of human epididymis protein 4 (HE4) has been observed in breast cancer and is associated with cancer progression; however, its role in ductal carcinoma in situ (DCIS) remains unclear. This study aimed to evaluate HE4 levels in serum and tissue from patients with DCIS and their correlation with clinicopathological features. Methods: Preoperative serum HE4 levels were measured in 59 DCIS patients. HE4 mRNA and protein expression in DCIS and adjacent normal tissues were assessed using RNAscope in situ hybridization and immunohistochemistry, respectively. An additional independent tissue microarray of 41 DCIS cases was also analyzed for HE4 expression in tumor tissue only. Furthermore, the BreastMark database was applied to assess the prognostic significance of HE4 expression in a larger cohort of breast cancer. Results: Serum HE4 levels (mean ± SD: 39.4 ± 11.9 pmol/L) were within the normal range and showed no significant correlation with clinicopathological parameters except menopausal status. HE4 expression was significantly higher in DCIS tissues compared to adjacent normal tissues, with a positive correlation between mRNA and protein levels (r = 0.771, p < 0.001). High HE4 mRNA and protein expression was associated with ER positivity, HER2 negativity, low stromal tumor-infiltrating lymphocyte density, and HR+/HER2- subtypes, but was not predictive of DCIS recurrence. In breast cancer patients, high HE4 expression was significantly correlated with improved survival outcomes. Conclusions: Although serum HE4 is not elevated in DCIS, high HE4 expression in tissue is associated with favorable clinicopathological features. These findings highlight the need for further investigation into the potential prognostic role of HE4.

The prognostic relevance of tumor-infiltrating lymphocytes (TILs) has so far been recognized in several solid tumors like in breast, endometrial and ovarian cancer-nonetheless, the immune contexture of squamous cell carcinomas of the vulva, analyzed by means of stromal (s) and intratumoral (i) TILs, remains yet to be elucidated.

In this study, we examined the immunooncological biomarkers sTILs and iTILs in 157 vulvectomy specimens with histologically diagnosed vulvar squamous cell carcinoma (VSCC) according to the standardized methodology proposed by the International Immunooncology Biomarkers Working Group in 2017. In a next step, we evaluated the association of infiltrating lymphocytes to traditional histopathological parameters such as infiltration depth and HPV related tumorigenesis. After determining optimal cut-off values using Receiver Operating Characteristic (ROC) curve analysis, we assessed the prognostic relevance of sTILs and iTILs with regard to overall survival, local recurrence, and metastasis using the Log-rank (Mantel-Cox) test and Fisher's exact test.

We propose optimal cut-off values of 5% for iTILs and 20% for sTILs analysis, which identify patients with a distinct superior survival rate (sTILs: p = 0.0137; iTILs: p = 0.0226). Furthermore, a low number of iTILs was associated with a higher risk of local recurrence in our study collective (p = 0.0432).

The fast and cost-effective determination of the histological biomarkers iTILs and sTILs yields prognostic relevance in vulvar cancer. A potential integration within the routine diagnostic workflow could be globally feasible, even in resource-poor settings.

IRF4, characterized by its unique helix-turn-helix DNA-binding motif, is a member of the interferon regulatory factor (IRF) family. It plays a critical role in regulating host defense mechanisms, including innate and adaptive immune responses, as well as oncogenesis. However, the precise role of IRF4 in malignant tumors remains poorly understood. In this study, we first investigated IRF4 gene expression across various cancer types and its distribution within different molecular and immunological subtypes, providing a comprehensive understanding of its expression patterns in pan-cancer. We further explored the interacting proteins, diagnostic significance, molecular characteristics, prognostic relevance, and biological functions of IRF4 in diverse cancers. Focusing on colorectal cancer (CRC), we conducted a detailed analysis of IRF4, examining its associations with clinical features and outcomes across multiple clinical subgroups and databases. Additionally, we assessed IRF4 expression at both transcriptional and translational levels in CRC tumor specimens using tissue microarrays. Our findings revealed that IRF4 expression varies significantly not only across cancer types but also among molecular and immunological subtypes. In CRC, elevated IRF4 expression was associated with poorer overall survival. Notably, IRF4 was predominantly expressed in immune cells and showed a strong correlation with tumor immune regulation. Given its high predictive accuracy for cancer outcomes and robust prognostic associations, IRF4 may serve as a valuable prognostic biomarker for CRC. In conclusion, IRF4 represents a unique molecular biomarker for pan-cancer prognosis and an independent prognostic risk factor for CRC. Its critical role in immune regulation also positions IRF4 as a promising target for immunotherapeutic strategies in CRC.