FOLFOX combined with cetuximab is a recommended first-line treatment regimen for RAS/BRAF wild-type metastatic colorectal cancer (mCRC). CAPEOX combined with cetuximab differs from the FOLFOX regimen by using oral capecitabine instead of continuous infusion of fluorouracil, offering greater convenience and cost-effectiveness with higher patient acceptance. However, the comparative efficacy of these two regimens remains debatable, necessitating further evidence to explore any differences in their efficacy. This study collected medical records of mCRC patients who were treated with CAPEOX or FOLFOX combined with cetuximab from 1 October 2021 to 16 October 2023 at Harbin Medical University Cancer Hospital and the First Hospital of Shanxi Medical University. Eligible patients were selected based on inclusion criteria and followed up through the hospital's follow-up system and telephone interviews. Kaplan-Meier survival analysis and Cox proportional hazards regression analysis were used to assess patients' progression-free survival (PFS) and overall survival (OS). A total of 71 eligible patients were enrolled in this study; 43 patients received CAPEOX combined with cetuximab (Group A, n  = 43), and 28 patients received FOLFOX combined with cetuximab (Group B, n  = 28). The two groups achieved similar median PFS (mPFS) and median OS (mOS), with mPFS of 18 months and 12 months, respectively ( P  = 0.23), and mOS of 33 months and 20 months, respectively ( P  = 0.21), with no statistically significant differences. The results of this study demonstrated that CAPEOX combined with cetuximab is an equally viable option for first-line treatment of RAS/BRAF wild-type mCRC as FOLFOX combined with cetuximab.

Meta-analysis is a useful method for combining evidence from multiple studies to detect treatment effects that could perhaps not be identified in a single study. While traditionally meta-analysis has assumed that populations of included studies are comparable, over recent years the development of precision medicine has led to identification of predictive genetic biomarkers which has resulted in trials conducted in mixed biomarker populations. For example, early trials may be conducted in patients with any biomarker status with no subgroup analysis, later trials may be conducted in patients with any biomarker status and subgroup analysis, and most recent trials may be conducted in biomarker-positive patients only. This poses a problem for traditional meta-analysis methods which rely on the assumption of somewhat comparable populations across studies. In this review, we provide a background to meta-analysis methods allowing for synthesis of data with mixed biomarker populations across trials.

For the methodological review, PubMed was searched to identify methodological papers on evidence synthesis for mixed populations. Several identified methods were applied to an illustrative example in metastatic colorectal cancer.

We identified eight methods for evidence synthesis of mixed populations where three methods are applicable to pairwise meta-analysis using aggregate data (AD), three methods are applicable to network meta-analysis using AD, and two methods are applicable to network meta-analysis using AD and individual participant data (IPD). The identified methods are described, including a discussion of the benefits and limitations of each method.

Methods for synthesis of data from mixed populations are split into methods which use (a) AD, (b) IPD, and (c) both AD and IPD. While methods which utilise IPD achieve superior statistical qualities, this is at the expense of ease of access to the data. Furthermore, it is important to consider the context of the decision problem in order to select the most appropriate modelling framework.

Single-agent MEK1/2 inhibition has been disappointing in clinical trials targeting RAS mutant (MT) cancers, probably due to upstream receptor activation, resulting in resistance. We previously found that dual c-MET/MEK1/2 inhibition attenuated RASMT colorectal cancer (CRC) xenograft growth. In this study, we assessed safety of MEK1/2 inhibitor PD-0325901 with c-MET inhibitor crizotinib and determined the optimal biological doses for subsequent clinical trials.

In this dose-escalation phase I trial, patients with advanced solid tumours received PD-0325901 with crizotinib, using a rolling-6 design to determine the maximum tolerable dose (MTD) and safety/tolerability. Blood samples for pharmacokinetics and skin biopsies were collected.

Twenty-five patients were recruited in 4 cohorts up to doses of crizotinib 200 mg B.D continuously with PD-0325901 8 mg B.D, days 1-21 every 28 days. One in six patients exhibited a dose-limiting toxicity at this dose level. Drug-related adverse events were in keeping with single-agent toxicity profiles. The best clinical response was stable disease in seven patients (29%).

PD-0325901/crizotinib can be given together at pharmacologically-active doses. The MTD for PD-0325901/crizotinib was 8 mg B.D (days 1-21) and 200 mg B.D continuously in a 28-days cycle. The combination was further explored with an alternate MEK1/2 inhibitor in RASMT CRC patients.

2014-000463-40.

The EXOsome and cell-free miRNAs of anti-EGFR ResistAnce (EXONERATE) study was an open-label, biomarker interventional study designed to develop, test, and validate a liquid biopsy predictive of progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) for first-line EGFR inhibitors in metastatic colorectal cancer (mCRC).

Patients with newly diagnosed RAS wild-type, chemotherapy-naïve mCRC, both right- and left-sided, were enrolled in two nationwide trials to receive cetuximab or panitumumab along with chemotherapy. The primary endpoint was 12-month PFS, which was hierarchically tested in left- and right-sided mCRCs to predict PFS, OS, and ORR.

Genome-wide small RNA sequencing identified 12 cell-free and 14 exosomal candidates that were differentially expressed in both plasma and tumor tissue of good versus poor responders (based on PFS <12 months). The 8 and 9 best performing candidates, respectively, were used to generate the EXONERATE assay. In left-sided mCRC, 65% were EXONERATE-high, correlating with shorter median PFS (9.5 vs. 18.5 months; P < 0.001). In the independent right-sided mCRC cohort, 80.8% were EXONERATE-high and experienced a similarly shorter median PFS (8.6 vs. 41.2 months; P = 0.0004). In the right-sided group, EXONERATE predicted PFS ≥12 months with 100% sensitivity. A linear relationship existed between EXONERATE values and response depth. Multivariate analysis revealed that EXONERATE predicts PFS and OS independently of tumor sidedness.

The EXONERATE assay robustly predicted PFS and OS outcomes in patients with mCRC, both right- and left-sided, before they received either panitumumab or cetuximab. It stratified PFS, OS, and ORR better than a right versus left approach.

Colorectal cancer (CRC) remains a significant global health challenge, demanding continuous advancements in treatment strategies. This review explores the complexities of targeting colorectal cancer stem cells (CSCs) and the mechanisms contributing to resistance to 5-fluorouracil (5-FU). The efficacy of 5-FU is enhanced by combination therapies such as FOLFOXIRI and targeted treatments like bevacizumab, cetuximab, and panitumumab, particularly in KRAS wild-type tumors, despite associated toxicity. Biomarkers like thymidylate synthase (TYMS), thymidine phosphorylase (TP), and dihydropyrimidine dehydrogenase (DPD) are crucial for predicting 5-FU efficacy and resistance. Targeting CRC-CSCs remains challenging due to their inherent resistance to conventional therapies, marker variability, and the protective influence of the tumor microenvironment which promotes stemness and survival. Personalized treatment strategies are increasingly essential to address CRC's genetic and phenotypic diversity. Advances in immunotherapy, including immune checkpoint inhibitors and cancer vaccines, along with nanomedicine-based therapies, offer promising targeted drug delivery systems that enhance specificity, reduce toxicity, and provide novel approaches for overcoming resistance mechanisms. Integrating these innovative strategies with traditional therapies may enhance the effectiveness of CRC therapy by addressing the underlying causes of 5-FU resistance in CSCs.

Fatal anaphylactic reactions to cetuximab remain a clinical issue, although they are associated with preexisting immunoglobulin E (IgE) directed against the galactose-α1,3-galactose epitope (α3Gal). We aimed to compare the clinical usefulness of the two assays and determine the prevalence of preexisting anti-α3Gal IgE.

An anti-α3Gal IgE assay was developed (70BP assay) and compared with a commercial assay [bovine thyroglobulin (bTG) assay]. Both assays were applied to two cohorts: 299 healthy blood donors and 41 patients with head and neck cancer treated with cetuximab, including four patients with a history of anaphylactic reaction (9.8%).

The prevalence of anti-α3Gal IgE was 6% and 5% using 70BP and bTG assays, respectively, in healthy blood donors. Among the head and neck cancer patients, the four who had an anaphylactic reaction were included in the seven (17.1%) and six (14.6%) patients with a signal above the detection threshold using the 70BP and bTG assays, respectively. This resulted in a sensitivity and negative predictive value of 100% for both assays, with a specificity of 91.9% and 94.6%, respectively, and a positive predictive value of 57.1% and 66.6% for the 70BP and bTG assays, respectively. Using an optimized threshold in the bTG assay, the prevalence of anti-α3Gal IgE in blood donors decreased to 1.3%, and five patients (12.2%) were eventually considered positive, giving a specificity of 97.3% and a positive predictive value of 80%.

The predictive value of anti-α3Gal IgE using these two assays was excellent and useful in clinical practice.

Subsequent lines of therapy for chemotherapy-resistant metastatic colorectal cancer (CRC) have shown limited efficacy. Herein, we retrospectively investigated the efficacy and safety of hepatic artery infusion chemotherapy (HAIC) using oxaliplatin plus 5-FU/FUDR in patients with unresectable colorectal liver metastases (CRLM) who progressed following standard chemotherapy regimens.

From March 2017 to April 2023, CRC patients with unresectable CRLM who progressed following standard chemotherapy and subsequently received HAIC oxaliplatin plus 5-FU/FUDR were evaluated. Objective response rate (ORR), disease control rate (DCR), median depth of tumor response (DpR), no evidence of disease (NED) rate, progression-free survival (PFS), overall survival (OS), and safety were assessed.

A total of 21 patients who progressed after a median of two (range: 1-4) lines of standard systemic chemotherapy were included. The ORR and DCR were 28.6 % and 95.2 %, respectively, with six patients reaching partial response. Additionally, the median DpR was 10.6 %, and seven patients underwent successful conversion surgery. Stratification revealed significantly better PFS in patients with liver-limited metastases compared to those with concurrent hepatic and extrahepatic metastases (P = 0.0003).

HAIC oxaliplatin plus 5-FU/FUDR is a robust regimen for treatment-resistant CRC patients with unresectable CRLM, particularly those with liver-limited disease.

Encorafenib + cetuximab (EC) is approved for previously treated BRAF V600E-mutant metastatic colorectal cancer (mCRC) based on the BEACON phase 3 study. Historically, first-line treatment of BRAF V600E-mutant mCRC with chemotherapy regimens has had limited efficacy. The phase 3 BREAKWATER study investigated EC+mFOLFOX6 versus standard of care (SOC) in patients with previously untreated BRAF V600E mCRC. The dual primary endpoint of progression-free survival is event driven; data were not mature at data cutoff. BREAKWATER met the other dual primary endpoint of objective response rate, demonstrating significant and clinically relevant improvement in objective response rate (EC+mFOLFOX6: 60.9%; SOC: 40.0%; odds ratio, 2.443; 95% confidence interval (CI): 1.403-4.253; 99.8% CI: 1.019-5.855; one-sided P = 0.0008). Median duration of response was 13.9 versus 11.1 months. At this first interim analysis of overall survival, the hazard ratio was 0.47 (95% CI: 0.318-0.691; repeated CI: 0.166-1.322). Serious adverse event rates were 37.7% versus 34.6%. The safety profiles were consistent with those known for each agent. BREAKWATER demonstrated a significantly improved response rate that was durable for first-line EC+mFOLFOX6 versus SOC in patients with BRAF V600E mCRC. ClinicalTrials.gov identifier: NCT04607421 .

Background/Objective: The prognostic value of specific hot-spot mutations within KRAS, NRAS, and BRAF genes in metastatic colorectal cancer (mCRC) genes remains debatable. This study explores whether certain KRAS, NRAS, and BRAF mutations are associated with the risk of all-cause mortality in mCRC. Methods: We retrospectively analyzed records of 494 patients with mCRC treated at the University of Texas Medical Branch between January 2016 and July 2023. Data on genetic mutations and clinicopathological features were collected for this analysis. We estimated survival probabilities and conducted multivariable Cox proportional hazards regression to evaluate the impact of specific mutations on all-cause mortality risk. Results:KRAS c.35G>T (p.Gly12Val) and c.34G>T (p.Gly12Cys) mutations were significantly associated with an increased risk of all-cause mortality in the overall mCRC population and the treated mCRC subgroup. KRAS c.38G>A (p.Gly13Asp) was significantly associated with an increased risk of all-cause mortality in the treated mCRC subgroup but BRAF c.1799T>A (p.Val600Glu) was significantly associated with an increased risk of all-cause mortality in the overall mCRC population. No significant association was observed between NRAS mutations and mortality risk in mCRC, possibly due to their lower frequency or different biological effects compared to KRAS and BRAF mutations. Conclusions: These findings suggest that specific KRAS [c.35G>T (p.Gly12Val), c.34G>T (p.Gly12Cys), and c.38G>A (p.Gly13Asp)] and BRAF c.1799T>A (p.Val600Glu) mutations may have prognostic value in mCRC. However, given the single-center study design and lack of direct therapeutic implications, larger multicenter studies are needed to substantiate these results and better define the clinical relevance of these mutations.

Colorectal cancer (CRC) is a major cause of cancer-related mortality worldwide, with a significant impact on public health. Current treatment options include surgery, chemotherapy, radiotherapy, molecular-targeted therapy, and immunotherapy. Despite advancements in these therapeutic modalities, resistance remains a significant challenge, often leading to treatment failure, poor progression-free survival, and cancer recurrence. Mechanisms of resistance in CRC are multifaceted, involving genetic mutations, epigenetic alterations, tumor heterogeneity, and the tumor microenvironment. Understanding these mechanisms at the molecular level is crucial for identifying novel therapeutic targets and developing strategies to overcome resistance. This review provides an overview of the diverse mechanisms driving drug resistance in sporadic CRC and discusses strategies currently under investigation to counteract this resistance. Several promising strategies are being explored, including targeting drug transport, key signaling pathways, DNA damage response, cell death pathways, epigenetic modifications, cancer stem cells, and the tumor microenvironment. The integration of emerging therapeutic approaches that target resistance mechanisms aims to enhance the efficacy of current CRC treatments and improve patient outcomes.

Metastatic colorectal cancer (mCRC) poses a high rate of morbidity and mortality despite various treatment advances. Cetuximab, an anti-EGFR, has shown promising efficacy in improving outcomes when combined with chemotherapy. Understanding its efficacy is essential for optimizing treatment strategies in mCRC. This systematic review and meta-analysis aims to evaluate the effectiveness of combining cetuximab with chemotherapy in mCRC.

PubMed and Google Scholar were systematically searched following the benchmarks indicated by PRISMA. The primary outcomes of the study were progression-free survival (PFS) and overall survival (OS). Statistical analyses were executed using Stata version 16.

The meta-analysis encompassed 25 studies involving 3788 mCRC patients. The median age spans from 18 to 77 years. The cetuximab plus chemotherapy exhibited a higher PFS and OS with a significant difference (PFS: HR = 0.79, 95% CI = 0.63-0.96, p < 0.01, I2 = 38% and OS: HR = 0.78, 95% CI = 0.60-0.91, p < 0.01, I2 = 47%) compared to the control group. Subgroup analysis based on randomized controlled trials demonstrated consistent treatment effects for PFS (HR = 0.77, 95% CI = 0.62-0.93) and OS (HR = 0.76, 95% CI = 0.61-0.88) in the cetuximab treatment group.

Combining cetuximab with chemotherapy offers a potential benefit in improving survival outcomes for metastatic colorectal cancer patients, as indicated by this study. These results suggest that cetuximab may be a valuable addition to mCRC treatment strategies, warranting further clinical investigation and integration into standard care.

The molecular characterization of early-stage (1-3) colorectal cancer (CRC) remains incomplete, as opposed to metastatic disease, where comprehensive genomic profiling (CGP) is routinely performed. This study aimed to characterize the genomics of stages 1-3 versus IV CRC, and the genomics of patients recurring within 1 year of diagnosis.

Patients from a de-identified CRC clinico-genomic database who received Foundation Medicine testing (FoundationOne/FoundationOne CDx) during routine clinical care at approximately 280 US cancer clinics between March 2014 and June 2023 were included. Genomic alterations (GA) were compared by Fisher's exact test.

A total of 4702 patients were included; 1902 with stages 1-3 and 2800 with stage 4 disease. Among patients with stages 1-3 disease, 546 recurred within 1 year. Patients staged 1-3 had higher prevalence of microsatellite instability (MSI-H, 11.4% vs 4.5%, P < .001), tumor mutational burden (TMB) ≥ 10 Mut/Mb (14.6% vs 6.8%, P < .001), GA in RNF43 (11.2% vs 5.7%, P < .001), MSH6 (3.9% vs 1.7%, P < .001), MLH1 (2.3% vs 0.7%, P < .001), and MSH2 (1.5% vs 0.6%, P < .01) compared to those with stage 4 disease. Patients who recurred within 1 year had higher prevalence of MSI-H (13.2% vs 4.4%, P < .001), TMB ≥ 10 Mut/Mb (16.2% vs 6.9%, P < .001), BRAF V600E (17.2% vs 7.9%, P < .003), GA in RNF43 (13.7% vs 5.3%, P < .001), MSH6 (4.2% vs 1.6%, P = .035), and BRCA1/2 (6.2% vs 3.0%, P = .030). On recurrence, more patients received targeted therapy when CGP was performed before versus after first-line therapy (43% vs 19%, P < .001).

Early-stage CRC patients can have distinct genomic profiles and CGP in this population can help expand access to targeted therapies.

The use of targeted drugs and immunotherapy has significantly impacted the treatment of Colorectal Cancer. However, horizontal comparison among various regimens is extremely rare. Therefore, we evaluated the survival efficacy of multiple treatment regimens of targeted therapy and/or immunotherapy with or without chemotherapy in patients with Colorectal Cancer.

A systematic search was conducted in PubMed, EMBASE, and Cochrane databases, covering the period from the establishment of the databases to October 29, 2024. To obtain articles that met the inclusion and exclusion criteria and contained the required data for conducting a network meta-analysis (NMA). The NMA evaluated overall survival (OS) and progression-free survival (PFS).

A total of 90 studies were identified, comprising a sample size of 33,167 subjects. In terms of PFS, compared with simple chemotherapy strategies, most of the other single or combined strategies are significantly effective, among which targeted therapy strategies have more advantages. Encorafenib + Binimetinib + Cetuximab (ENC-BIN-CET) shows significant benefits in all comparisons except when compared with Chemotherapy + Cetuximab + Dalotuzumab (Chemo-CET-DAL), Encorafenib + Cetuximab (ENC-CET), and Panitumumab + Sotorasib (PAN-SOT). The ENC-CET and PAN-SOT targeted strategies also show significant benefits. Pembrolizumab (PEM) monotherapy has advantages over all others except when it is not superior to some targeted strategies. Chemotherapy + Bevacizumab + Atezolizumab is only inferior to some strategies. In terms of OS, the combinations of Chemotherapy + Bevacizumab, ENC-CET, Chemotherapy + Panitumumab, and ENC-BIN-CET are superior to simple chemotherapy regimens. ENC-BIN-CET shows OS benefits in all comparisons except some. ENC-CET significantly improves OS in most cases, and PEM also significantly improves OS in some regimens. In the probability ranking of OS and PFS, ENC-BIN-CET has the best effect, followed by ENC-CET.

In conclusion, pembrolizumab is still effective in prolonging survival. Dual- and triple-drug targeted strategies are the best in terms of OS and PFS, and the combination of targeted immunotherapy and chemotherapy also works. However, not all combinations are beneficial. As targeted drugs play an active role, specific drugs for colorectal cancer regimens should be carefully selected.

The FIRE-4 study randomly assigned patients with first-line RAS wild-type (RASwt) metastatic colorectal cancer to either flourouracil (FU), folinic acid, and irinotecan (FOLFIRI) plus cetuximab until progression or intolerable toxicity (standard arm) or to FOLFIRI plus cetuximab followed by a switch maintenance treatment using FU plus bevacizumab (experimental arm). Here, we investigate the relevance of liquid biopsy (LB) RAS and BRAF testing compared with tissue-based analyses.

LBs were taken at baseline and during treatment and were analyzed for RAS and BRAFV600E mutations using the in vitro diagnostics-certified ONCOBEAM RAS procedure (Sysmex Inostics) and digital-droplet polymerase chain reaction technology.

Six hundred seventy-two RASwt patients were randomly assigned. LBs of 540 patients were evaluable at baseline. Of those, 70 (13%) were RAS mutant (RASmut) and 38 (7%) BRAFV600E mutant. RASmut patients had significantly shorter survival compared with RASwt patients (progression-free survival [PFS], 9.0 months v 11.5 months; P < .001; hazard ratio [HR], 1.66; overall survival [OS], 22.1 months v 33.6 months; P < .001; HR, 1.85). RASmut patients had a numerically greater benefit from early switch maintenance compared with continuation of FOLFIRI/cetuximab (PFS, 10.1 months v 6.4 months; HR, 0.82; OS, 24.9 months v 16.3 months; HR, 0.57). Patients with a BRAFV600E mutation in LB showed poor outcome (PFS, 5.4 months; OS, 12.0 months). On the basis of serial LB analyses, the conversion rate from RASwt to RASmut at disease progression was significantly higher in the arm with continuous cetuximab administration than in the switch maintenance arm.

LB allows the detection of RAS and BRAF mutations in patients deemed RASwt on the basis of tissue analyses. These patients show outcome characteristics expected for RAS- and BRAF-mutant patients in tissue. The study thus confirms the high clinical relevance of LB performed at baseline before the start of therapy.

The burden of colorectal cancer (CRC) is high in the Asia-Pacific region, and several countries in this region have among the highest and/or fastest growing rates of CRC in the world. A significant proportion of patients will present with or develop metastatic CRC (mCRC), and BRAFV600E-mutant mCRC represents a particularly aggressive phenotype that is less responsive to standard chemotherapies. In light of recent therapeutic advances, an Asia-Pacific expert consensus panel was convened to develop evidence-based recommendations for the diagnosis, treatment, and management of patients with BRAFV600E-mutant mCRC. The expert panel comprised nine medical oncologists from Australia, Hong Kong, Singapore, and Taiwan (the authors), who met to review current literature and develop eight consensus statements that describe the optimal management of BRAFV600E-mutant mCRC in the Asia-Pacific region. As agreed by the expert panel, the consensus statements recommend molecular testing at diagnosis to guide individualized treatment decisions, propose optimal treatment pathways according to microsatellite stability status, advocate for more frequent monitoring of BRAFV600E-mutant mCRC, and discuss local treatment strategies for oligometastatic disease. Together, these expert consensus statements are intended to optimize treatment and improve outcomes for patients with BRAFV600E-mutant mCRC in the Asia-Pacific region.

Patients diagnosed with metastatic colorectal cancer (mCRC) have a poor prognosis with survival ranging 2-3 years. The prevalence of human epidermal growth factor receptor 2 (HER2) amplification is approximately 3-4% in mCRC and increases up to 8% in patients with KRAS/NRAS/BRAF wild-type (WT) CRC tumors. Tucatinib is a highly selective HER2-directed tyrosine kinase inhibitor that, in combination with trastuzumab, has demonstrated clinically meaningful activity in patients with chemotherapy-refractory, HER2-positive (HER2+), RAS WT mCRC in the MOUNTAINEER trial. The MOUNTAINEER-03 phase III trial is designed to investigate the efficacy and safety of first-line tucatinib in combination with trastuzumab and modified FOLFOX6 (mFOLFOX6) versus standard of care (mFOLFOX6 plus bevacizumab or cetuximab) in patients with untreated HER2+, RAS WT locally advanced unresectable or mCRC. MOUNTAINEER-03 will include two arms of approximately 400 patients randomized 1:1 to either treatment arm. The primary endpoint is progression-free survival per RECIST v1.1 by blinded independent central review (BICR). Key secondary endpoints are overall survival and confirmed objective response rate (according to RECIST v1.1 per BICR). Safety assessments will include surveillance and recording of adverse events, physical examination findings, vital signs, cardiac assessments, Eastern Cooperative Oncology Group performance status, concomitant medications, and laboratory tests.Clinical trial registration: NCT05253651 (ClinicalTrials.gov).

BRAF mutations occur in 5-10% of metastatic colorectal cancer (mCRC) cases, but their implications for prognosis and optimal treatment remain unclear.

This multicenter, prospective observational study analyzed 377 RAS wild-type cases from 511 patients across 32 centers, using PCR-based methods.

BRAF mutations were identified in 21% (79/377) of cases, predominantly V600E (89.9%) with a minority of non-V600E (10.1%). Microsatellite instability (MSI) testing revealed MSI-high in 11.3%, exclusively among V600E cases. V600E mutations were linked to right-sided tumors, poor differentiation, and elevated CA19-9 levels. Median survival was significantly lower in V600E cases compared to BRAF wild-type (12.4 vs. 37.5 months, HR 3.25, p < 0.001) and marginally lower non-V600E cases (12.4 vs. 34.7 months, HR 0.61, p = 0.057). Chemotherapy regimens (doublet vs. triplet) and targeted treatments (bevacizumab vs. anti-EGFR) showed no significant survival differences in V600E patients. Similarly, RAS/BRAF wild-type patients had comparable survival with bevacizumab versus anti-EGFR, even for left-sided tumors.

These findings highlight distinct clinical and prognostic profiles for BRAF V600E and non-V600E mutations, while treatment choice appears to have limited impact on survival in these subgroups or RAS/BRAF wild-type cases.

MAPK pathway inhibitors (MAPKi) are increasingly used in the treatment of advanced colorectal cancer, but often produce short-lived responses in patients. Although acquired resistance by de novo mutations in tumors have been found to reduce response in some patients, additional mechanisms underlying the limited response durability of MAPK targeting therapy remain unknown. Here, we denote new contributory tumor biology and provide insight on the impact of tumor plasticity on therapy response. Analysis of MAPKi treated patients revealed activation of stemness programs and increased ASCL2 expression, which are associated with poor outcomes. Greater ASCL2 with MAPKi treatment was also seen in patient-derived CRC models, independent of driver mutations. We find ASCL2 denotes a distinct cell population, arising from phenotypic plasticity, with a proliferative, stem-like phenotype, and decreased sensitivity to MAPKi therapy, which were named adaptive plasticity tumor (APT) cells. MAPK pathway suppression induces the APT phenotype in cells, resulting in APT cell enrichment in tumors and limiting therapy response in preclinical and clinical data. APT cell depletion improved MAPKi treatment efficacy and extended MAPKi response durability in mice. These findings uncover a cellular program that mitigates the impact of MAPKi therapies and highlights the importance of addressing tumor plasticity to improve clinical outcomes.

Cancers of the digestive system are major contributors to global cancer-associated morbidity and mortality, accounting for 35% of annual cases of cancer deaths. The etiologies, molecular features, and therapeutic management of these cancer entities are highly heterogeneous and complex. Over the last decade, genomic and functional studies have provided unprecedented insights into the biology of digestive cancers, identifying genetic drivers of tumor progression and key interaction points of tumor cells with the immune system. This knowledge is continuously translated into novel treatment concepts and targets, which are dynamically reshaping the therapeutic landscape of these tumors. In this review, we provide a concise overview of the etiology and molecular pathology of the six most common cancers of the digestive system, including esophageal, gastric, biliary tract, pancreatic, hepatocellular, and colorectal cancers. We comprehensively describe the current stage-dependent pharmacological management of these malignancies, including chemo-, targeted, and immunotherapy. For each cancer entity, we provide an overview of recent therapeutic advancements and research progress. Finally, we describe how novel insights into tumor heterogeneity and immune evasion deepen our understanding of therapy resistance and provide an outlook on innovative therapeutic strategies that will shape the future management of digestive cancers, including CAR-T cell therapy, novel antibody-drug conjugates and targeted therapies.

Cancer remains a leading cause of mortality globally and a major health burden, with chemotherapy often serving as the primary therapeutic option for patients with advanced-stage disease, partially compensating for the limitations of non-curative treatments. However, the emergence of chemotherapy resistance significantly limits its efficacy, posing a major clinical challenge. Moreover, heterogeneity of resistance mechanisms across cancer types complicates the development of universally effective diagnostic and therapeutic approaches. Understanding the molecular mechanisms of chemoresistance and identifying strategies to overcome it are current research focal points. This review provides a comprehensive analysis of the key molecular mechanisms underlying chemotherapy resistance, including drug efflux, enhanced DNA damage repair (DDR), apoptosis evasion, epigenetic modifications, altered intracellular drug metabolism, and the role of cancer stem cells (CSCs). We also examine specific causes of resistance in major cancer types and highlight various molecular targets involved in resistance. Finally, we discuss current strategies aiming at overcoming chemotherapy resistance, such as combination therapies, targeted treatments, and novel drug delivery systems, while proposing future directions for research in this evolving field. By addressing these molecular barriers, this review lays a foundation for the development of more effective cancer therapies aimed at mitigating chemotherapy resistance.

The impact of sidedness on survival of later-line treatment in patients with metastatic colorectal cancer (mCRC) is undetermined. This study aimed to investigate the association between sidedness and survival among chemotherapy refractory patients with mCRC treated with trifluridine/tipiracil (TAS-102) or regorafenib or both.

Patients with mCRC treated with TAS-102 or regorafenib between 2015 and 2020 was retrospectively collected. Patients were stratified into TAS-102 first and regorafenib first, then subdivided into TAS-102 followed by regorafenib (T-R) and regorafenib followed by TAS-102 (R-T) groups. The oncologic outcomes were presented with time-to-treatment failure (TTF) and overall survival (OS).

After matching, 376 TAS-102 patients and 376 regorafenib patients were included for outcomes comparison. TTF had insignificant differences while OS was significantly different between TAS-102 and regorafenib groups. Median TTF and OS were 1.9 months versus 2.0 months (P = .701) and 9.1 months versus 7.0 months (P = .008) in TAS-102 and regorafenib, respectively. The OS benefits were consistent regardless primary tumor location. Subgroup analysis with 174 T-R patients and 174 R-T patients was investigated for treatment sequences. TTF and OS had significant differences in both groups. Median TTF and OS were 8.5 months versus 6.3 months (P = .001) and 14.4 months versus 12.6 months (P = .035) in T-R and R-T groups, respectively. The TTF and OS benefits were persisted regardless primary tumor location.

TAS-102 first provided a better survival benefit in chemotherapy refractory patients with mCRC across all sidedness. Further prospective studies are warranted to validate our conclusions.

To date, the clinical benefit and utility of implementing a DPYD/UGT1A1 pharmacogenetic-informed therapy with fluoropyrimidines and/or irinotecan have not been prospectively investigated.

To examine clinically relevant toxic effects, hospitalizations, and related costs while preserving treatment intensity and efficacy outcomes in patients with gastrointestinal cancer.

This nonprespecified secondary analysis stems from Pre-Emptive Pharmacogenomic Testing for Preventing Adverse Drug Reactions (PREPARE), a multicenter, controlled, open, block-randomized, crossover implementation trial conducted from March 7, 2017, to June 30, 2020, and includes data from Italy according to a sequential study design. The study population included 563 patients (intervention, 252; control [standard of care], 311) with gastrointestinal cancer (age ≥18 years) who were eligible for fluoropyrimidine and/or irinotecan treatment. Data analysis for the present study was performed from May 27 to October 10, 2024.

Participants with actionable variants (DPYD*2A, DPYD*13, .DPYD c.2846A>T, and DPYD c.1236G>A for fluoropyrimidines, and UGT1A1*28, UGT1A1*6, and UGT1A1*27 for irinotecan) received drug or dose adjustments based on Dutch Pharmacogenetics Working Group recommendations.

The primary outcome was clinically relevant toxic effects (National Cancer Institute Common Terminology Criteria for Adverse Events grade ≥4 hematologic, grade ≥3 nonhematologic, or causing hospitalization, fluoropyrimidines and/or irinotecan causally related). Secondary outcomes included hospitalization rates, toxic effect management costs, intensity of treatment, quality-adjusted life-years, and 3-year overall survival.

Overall, 1232 patients were enrolled in Italy, with 563 included in this analysis (317 [56.3%] men; median age, 68.0 [IQR, 60.0-75.0] years). In the intervention arm, carriers of any actionable genotype exhibited a 90% lower risk of clinically relevant toxic effects compared with the control arm (odds ratio, 0.1; 95% CI, 0.0-0.8; P = .04). They also presented higher toxic effect management costs per patient ($4159; 95% CI, $1510-$6810) compared with patients in the intervention arm ($26; 95% CI, 0-$312) (P = .004) and a higher rate of hospitalization (34.8% vs 11.8%; P = .12). The differences were not significant among all patients. Three-year overall survival did not differ significantly between arms, while quality-adjusted life-years significantly improved in the intervention arm. The pharmacogenetics-informed approach did not manifest a detrimental effect on treatment intensity in actionable genotype carriers.

In this secondary analysis of PREPARE, pretreatment application of DPYD- and UGT1A1-guided treatment appeared to increase safety and reduce hospitalizations and related costs in patients with gastrointestinal cancer. Clinical benefit did not appear to be affected.

ClinicalTrials.gov Identifier: NCT03093818.

Individualized treatment of colorectal cancer liver metastases (CRLM) remains challenging due to differences in the severity of metastatic disease and tumour biology. Exploring specific prognostic risk subgroups is urgently needed. The current study aimed to investigate the prognostic value of chromosomal instability (CIN) in patients with initially resectable CRLM and the predictive value of CIN for the efficacy of bevacizumab.

Ninety-one consecutive patients with initially resectable CRLM who underwent curative liver resection from 2006 to 2018 at Sun Yat-sen University Cancer Center were selected for analysis. CIN was evaluated by automated digital imaging systems. Immunohistochemistry (IHC) was performed to detect interleukin-6 (IL-6), vascular endothelial growth factor A (VEGFA) and CD31 expression in paraffin-embedded specimens. Recurrence-free survival (RFS) and overall survival (OS) were analysed using the Kaplan-Meier method and Cox regression models.

Patients with high chromosomal instability (CIN-H) had a worse 3-year RFS rate (HR, 1.953; 95% CI, 1.001-3.810; p = 0.049) and a worse 3-year OS rate (HR, 2.449; 95% CI, 1.150-5.213; p = 0.016) than those with low chromosomal instability (CIN-L). CIN-H was identified as an independent prognostic factor for RFS (HR, 2.569; 95% CI, 1.078-6.121; p = 0.033) and OS (HR, 3.852; 95% CI, 1.173-12.645; p = 0.026) in the multivariate analysis. The protein levels of IL-6, VEGFA and CD31 were upregulated in patients in the CIN-H group compared to those in the CIN-L group in both primary tumour and liver metastases tissues. Among them, 22 patients with recurrent tumours were treated with first-line bevacizumab treatment and based on the clinical response assessment, disease control rates were adversely associated with chromosomal instability (p = 0.043).

Our study showed that high chromosomal instability is a negative prognostic factor for patients with initially resectable CRLM after liver resection. CIN may have positive correlations with angiogenesis through expression of IL-6-VEGFA axis and be used as a potential predictor of efficacy of bevacizumab.

The combination of preoperative chemotherapy and surgical treatment has been shown to significantly enhance the prognosis of colorectal cancer with liver metastases (CRLM) patients. Nevertheless, as a result of variations in clinicopathological parameters, the prognosis of this particular group of patients differs considerably. This study aimed to develop and evaluate Cox proportional risk regression model and competing risk regression model using two patient cohorts. The goal was to provide a more precise and personalized prognostic evaluation system.

We collected information on individuals who had a pathological diagnosis of colorectal cancer between 2000 and 2019 from the Surveillance, Epidemiology, and End Results (SEER) Database. We obtained data from patients who underwent pathological diagnosis of colorectal cancer and got comprehensive therapy at the hospital between January 1, 2010, and June 1, 2022. The SEER data collected after screening according to the inclusion and exclusion criteria were separated into two cohorts: a training cohort (training cohort) and an internal validation cohort (internal validation cohort), using a random 1:1 split. Subgroup Kaplan-Meier (K-M) survival analyses were conducted on each of the three groups. The data that received following screening from the hospital were designated as the external validation cohort. The subsequent variables were chosen for additional examination: age, gender, marital status, race, tumor site, pretreatment carcinoembryonic antigen level, tumor size, T stage, N stage, pathological grade, number of tumor deposits, perineural invasion, number of regional lymph nodes examined, and number of positive regional lymph nodes. The primary endpoint was median overall survival (mOS). In the training cohort, we conducted univariate Cox regression analysis and utilized a stepwise regression approach, employing the Akaike information criterion (AIC) to select variables and create Cox proportional risk regression models. We evaluated the accuracy of the model using calibration curve, receiver operating characteristic curve (ROC), and area under curve (AUC). The effectiveness of the models was assessed using decision curve analysis (DCA). To evaluate the non-cancer-related outcomes, we analyzed variables that had significant impacts using subgroup cumulative incidence function (CIF) and Gray's test. These analyses were used to create competing risk regression models. Nomograms of the two models were constructed separately and prognostic predictions were made for the same patients in SEER database.

This study comprised a total of 735 individuals. The mOS of the training cohort, internal validation cohort, and QDU cohort was 55.00 months (95%CI 46.97-63.03), 48.00 months (95%CI 40.65-55.35), and 68.00 months (95%CI 54.91-81.08), respectively. The multivariate Cox regression analysis revealed that age, N stage, presence of perineural infiltration, number of tumor deposits and number of positive regional lymph nodes were identified as independent prognostic risk variables (p < 0.05). In comparison to the conventional TNM staging model, the Cox proportional risk regression model exhibited a higher C-index. After controlling for competing risk events, age, N stage, presence of perineural infiltration, number of tumor deposits, number of regional lymph nodes examined, and number of positive regional lymph nodes were independent predictors of the risk of cancer-specific mortality (p < 0.05).

We have developed a prognostic model to predict the survival of patients with synchronous CRLM who undergo preoperative chemotherapy and surgery. This model has been tested internally and externally, confirming its accuracy and reliability.

Substantial progress is being made in the development of novel therapies directed against colorectal cancer. The discovery of various molecular markers and advances in tumor profiling have facilitated the development of new targeted agents and immunotherapy. Not only have these drugs improved progression-free survival and even overall survival in some cases, but their related outcomes have also raised questions as to how to best combine or sequence therapies for even greater efficacy. Furthermore, we are beginning to understand how these combination therapies may yield for greater therapeutic response for patients with microsatellite stable colorectal cancer for which there is much need for improvement. In this article, we review recent trial data and explore the outcomes of various targeted therapies and immunotherapies for patient with advanced colorectal cancer.

We aimed to compare FOLFIRI and bevacizumab with FOLFIRI and aflibercept in terms of overall survival (OS), progression-free survival (PFS) and safety in patients with RAS-mutant metastatic colon cancer who progressed after first-line FOLFOX or XELOX and bevacizumab treatment. This retrospective study included 243 patients from 15 different centres in Turkey. The endpoints of the study were OS, PFS and safety and side effect outcomes. The median age of the patients included in the study was 60 (21-85) years. Of the patients enrolled in the study, 114 patients (46.9%) received aflibercept and 129 patients (53.1%) received bevacizumab. Median OS was 11.2 (95% CI: 9.1-13.2) months in patients receiving FOLFIRI + aflibercept and 14.1 (95% CI: 11.2-17.1) months in patients receiving FOLFIRI + bevacizumab. The median PFS was 5.7 (95% CI: 4.9-6.5) months in the aflibercept arm and 7.7 (95% CI: 7.1-8.3) months in the bevacizumab arm. Grade 3-4 side effects were observed in 58 (50.9%) patients in the aflibercept arm and 33 (25.6%) patients in the bevacizumab arm. As a result of our study, in patients with metastatic RAS-mutant colon cancer who progressed after first-line oxaliplatin-based doublet chemotherapy and bevacizumab, better OS and PFS results were obtained in patients receiving bevacizumab with FOLFIRI compared to patients receiving aflibercept with FOLFIRI. In addition, the side effect profile was more tolerable in the bevacizumab arm.

Metastatic colorectal cancer is a leading cause of cancer-related death across the world. The treatment paradigm has shifted away from systemic chemotherapy alone to include targeted therapy and immunotherapy. The past two decades have been characterized by increased investigation into molecular profiling of colorectal cancer. These molecular profiles help physicians to better understand colorectal cancer biology among patients with metastatic disease. Additionally, improved data on genetic pathways allow for specific therapies to be targeted at the underlying molecular profile. Investigation of the EGFR, VEGF, HER2, and other pathways, as well as deficient mismatch repair, has led to the development of multiple targeted therapies that are now utilized in the National Comprehensive Cancer Network guidelines for colon and rectal cancer. While these new therapies have contributed to improved survival for metastatic colorectal cancer, long-term survival remains poor. Additional investigation to understand resistance to targeted therapy and development of new targeted therapy is necessary. New therapies are under development and are being tested in the preclinical and clinical settings. The aim of this review is to provide a comprehensive evaluation of molecular profiling, currently available therapies, and ongoing obstacles in the field of colorectal cancer.

Understanding the mutational landscape of colon cancer (CC) is crucial for targeted therapy development. Microsatellite instability (MSI-H), rat sarcoma (RAS), and B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutations (MT) are pivotal markers. Further investigation into clinicopathological features of RAS and BRAF MT in microsatellite stable (MSS) and MSI-H tumors is warranted.

A retrospective analysis of 4883 localized CC patients (pts.) was conducted. Molecular profiling assessed MSI, KRAS, NRAS, and BRAF MT. Correlation with clinicopathological data employed ANOVA and Chi-square tests. Disease-free survival (DFS) and overall survival (OS) were analyzed adjusting for age, gender, sidedness, UICC stage, Charlson Comorbidity Index (CCI). A Cox model incorporated all variables as covariates.

This analysis included 4883 pts. (2302 female/2572 male, 3865 (79.2%) MSS, 1018 (20.8%) MSI-H). MSS pts. had more All-Wild Type (WT), KRAS MT, and NRAS MT tumors vs. MSI-H pts. (42.1% vs. 21.1%; 39.8% vs. 15.4%; 3.6% vs. 0.7%; p<0.001 for each). BRAF MT tumors (95.5% BRAF V600E MT) were more prevalent in MSI-H individuals (62.8% vs. 8.1%, p<0.001). KRAS and BRAF MT tumors were more frequently right-sided, while BRAF MT tumors were associated with female gender, advanced disease stage, lymph node positivity, and poorer differentiation in the MSS subset (p<0.001). Common KRAS mutations included p.G12D (30.44%) and p.G12V (21.3%) in MSS and p.G13D (28.9%) and p.G12D (22.37%) in MSI-H. NRAS MT tumors were dominated by codon 61 mutations (51.7%). Survival analysis revealed worst prognosis in BRAF MT MSS tumors (DFS: HR 1.74 (95% CI 1.15-2.62, p=0.009; OS: HR 1.61 (95% CI 0.99-2.6), p=0.055). The 3-years DFS and 5-years OS rates were lowest in this subset (61.6% and 57.7% respectively).

These findings highlight the complex interplay between molecular subtypes, clinicopathological features, and survival outcomes in early CC. Further research is needed to elucidate underlying mechanisms and develop personalized treatment strategies.

This narrative review explores the efficacy and applicability of anti-EGFR therapy as the first-line treatment for patients with RAS wild-type (WT) left-sided metastatic colorectal cancer (mCRC). It critically examines current guidelines, along with recent evidence in the literature, to assess whether it should be universally applied.

Recent evidences highlight the variability of the response to anti-EGFR therapies due to molecular diversity and several clinical factors, such as RAS mutational status and primary tumor location. Anti-EGFR plus chemotherapy is the standard first-line treatment for most patients with MSS, RAS-WT, left-sided mCRC. Whether this combination is the best treatment for these patients remains an open question. This review delves into the role of EGFR inhibition in mCRC, focusing on clinical factors and the knowledge of biology, molecular targets, and biomarkers. It underscores the crucial role of a personalized approach, empowering healthcare providers and equipping them with the confidence to make informed decisions.

Background/Objectives: Metastatic colorectal cancer remains a fatal disease, with a 5-year survival rate lower than 15%. The most common metastatic sites are the lungs and the liver, while skin metastases are very rare and often indicate a poor prognosis with a lower survival rate. Methods. Herein, we present the clinical case of a 62-year-old female patient with rectal cancer metastases to the skin of the anogenital and abdominal regions, diagnosed 2 years after completion of treatment of the underlying disease. Results: Histological examination of the skin lesions revealed adenocarcinoma, and expression of the same immunohistochemical markers was also found in the primary tumor and in the cutaneous metastases. However, next-generation sequencing demonstrated differences in the mutational profiles of the primary tumor and metastasis to the skin. Somatic mutations in the APC, TP53, and PTPN11 genes were revealed in primary rectal adenocarcinoma, but another pathogenic TP53 mutation and a frameshift variant in the DYNC1I1 gene were found in cutaneous metastases. The patient underwent several courses of FOLFOX6 chemotherapy in combination with bevacizumab, but the treatment was unsuccessful. An analysis of 50 clinical cases from the literature concerning various manifestations of cutaneous metastases of rectal cancer showed a median survival of 8.5 months from the time of detection of the skin lesions. Conclusions: In this regard, careful skin examination of patients with rectal cancer and timely detection of cutaneous metastases are essential steps in the follow-up of patients who have undergone treatment of the primary tumor.

Metastatic CRC is considered as a heterogenous disease. Its management is therefore complex and dynamic. In order the give a ready reference to community oncologists, we developed this real world recommendations.

A group of experts with academic background and real world experience in mCRC got together. We reviewed the current literature and the insights gained from our real world experience. Based on the same we put together these recommendations.

Molecular testing should be done wherever possible. Most of these patients will be treated with a palliative approach. Doublet chemotherapy is a long-standing standard of care. Triplet therapy may be offered where a more aggressive approach is indicated. Combination with anti -vascular endothelial growth factor antibodies and/or anti EGFR antibodies is also considered standard. In the first-line setting, pembrolizumab can be used for patients with mCRC and microsatellite instability-high or deficient mismatch repair tumours; Left and right sided tumours are distinct entities. Combination of chemotherapy and targeted therapy is used as per individual patient and tumour characteristics.Oligometastatic disease can be approached with potentially curative intent. Cytoreductive surgery plus chemotherapy can be offered to selected patients with peritoneal only metastases. Stereotactic body radiation therapy can be used as local therapy for patients with oligometastatic liver only disease who cannot be taken up for surgery. New strategies include induction-maintenance chemotherapy and perioperative chemotherapy. All drugs/ regimen included as standard of care in the first line can also be used in subsequent lines. Specific targetable driver mutation tumours can be treated accordingly with their complementary biological therapy.

Multidisciplinary team management and shared decision making are possible when patient and caregivers choose to become active participants.