Cutaneous T-cell lymphomas (CTCLs) are a type of non-Hodgkin lymphoma that usually involves the skin. It has different subtypes including mycosis fungoides (MFs), Sézary syndrome (SS), primary cutaneous anaplastic large lymphoma (PC-ALCL), lymphomatoid papulosis (LyP), and subcutaneous panniculitis-like T-cell lymphoma (SPTCL). There are several reports of incidence, relapse, or progression of CTCLs by using specific drugs. We aim to identify drug- and vaccine-induced CTCL characteristics. A systematic search was conducted using MeSH terms/keywords: CTCL and drug-induced or drug-associated or vaccine-associated or vaccine induced through PubMed/Medline, Scopus, Web of Science, and Embase until May 10, 2024. Out of 14,031 papers, 60 articles were included, involving 71 patients with a mean age of 53.5 ± 17 years. Among them, 52.1% were male. Medications were categorized into four groups: conventional, biologics, small molecules, and vaccines. The most frequently reported medications in the first group were fingolimod (n = 8) and methotrexate (n = 7). Infliximab (n = 6) and etanercept (n = 5) were the most commonly reported biologics. Pfizer-BioNTech (n = 11) vaccine and JAK inhibitors (n = 3) were the most reported vaccine and small molecules. LyP (n = 17) was the most frequently reported type of CTCL, followed by PC-ALCL (n = 13), MF (n = 11), SS (n = 8), and SPTCL (n = 8). The most common underlying conditions were rheumatoid arthritis (n = 15) and multiple sclerosis (n = 10). Twenty patients (28%) experienced disease regression after discontinuing the drug, with a mean ± SD of 8.6 ± 8.8 weeks. In 14 patients (20%), chemotherapy and/or radiotherapy were initiated. Six patients passed away after being diagnosed with CTCL: two because of CTCL recurrence and four because of other complications. It is important recognizing CTCL as a possible, although rare, adverse effect of certain drugs and vaccines, and taking a history of vaccinations, especially COVID-19 vaccines, and immunosuppressive drugs such as fingolimod, TNF-a inhibitors, and methotrexate.

Cutaneous T-cell lymphoid neoplasms in childhood are exceedingly rare, presenting with a wide spectrum of clinical presentation and outcomes. Due to numerous clinical and pathological mimics, an integrated evaluation of clinical, histopathological, immunohistochemical, and molecular findings is critical for a diagnosis. Here, we review the clinical and pathological features, updated classifications, and critical differential diagnoses of cutaneous T-cell lymphoid neoplasms in children.

Primary cutaneous anaplastic large cell lymphoma (pcALCL) is a type of skin T-cell lymphoma with a favorable prognosis. Some patients may experience recurrence, but systemic involvement is rare. Some studies suggest that systemic progression is associated with poor prognosis. The value of 18F-FDG PET/CT in diagnosing lymphoma has been recognized, but there is often controversy over the application value of 18F-FDG PET/CT in pcALCL. We present a rare case of pcALCL involving multiple systemic lesions, monitored and evaluated using 18F-FDG PET/CT to assist in clinical treatment decisions. Through this case, we consider that 18F-FDG PET/CT has significant value in diagnosing pcALCL. However, more clinical cases are needed to confirm whether high FDG uptake is associated with the invasiveness of pcALCL and the impact of high FDG uptake and Ki-67 expression on the progression and prognosis of pcALCL.

Anaplastic large cell lymphoma (ALCL) is a rare T-cell lymphoma characterized by CD30 expression. This report describes the case of a 10-year-old female who presented with non-resolving cutaneous lesions initially treated as a bacterial infection. A biopsy confirmed the diagnosis of anaplastic lymphoma kinase-negative (ALK-negative) ALCL with cutaneous and nodal involvement. Further imaging revealed neoplastic uptake in the right lung, and the patient was diagnosed with Murphy stage II ALCL. She began chemotherapy according to established pediatric oncology protocols. ALCL presents diagnostic challenges due to its non-specific symptoms, which can mimic benign conditions. This case underscores the importance of early biopsy and molecular testing when standard treatments fail. Early recognition and routine examinations, including lymph node assessments and skin biopsies, are critical for improving patient outcomes, as timely diagnosis leads to more effective treatment options and potential remission.

Primary cutaneous anaplastic large-cell lymphoma (PC-ALCL) is a rare T-cell lymphoma belonging to the CD30 + T-cell lymphoproliferative disorders. The case of PC-ALCL in the temporal region is exceedingly rare. Herein, we report a case of PC-ALCL involving the temporal region mimicking infratemporal space infection.

A 78-year-old woman presented to maxillofacial surgery service with a 6-month history of swelling and pain in the left side of her face. Laboratory investigations found an elevated C-reactive protein (CRP). Imaging findings showed enlarged lymph nodes and extensive thickening of subcutaneous tissue of the left temples. Based on these findings, the infratemporal space infection was suspected initially. The patient underwent incision and drainage, and we unexpectedly found no pus in the lesion area. Incisional biopsy showed necrosis and extensive involvement of the left temples by a diffuse infiltrate containing large, atypical cells. The tumor cells were positive for CD30, CD3, Ki67. They were negative for ALK (SP8), CD5, CD8, CD20 and PAX5. After considering these findings, a diagnosis of PC-ALCL was rendered. The patient was admitted to the lymphoma department for systemic chemotherapy and no relapse occurred during a follow-up period of six months.

This report suggests that if there are suspicious intraoperative manifestations, carrying out a biopsy simultaneously, using Hematoxylin and eosin (HE) staining, and a comprehensive Immunohistochemistry (IHC) panel are essential to diagnosing PC-ALCL to prevent misdiagnosis.

Primary cutaneous anaplastic large cell lymphoma (PC-ALCL) differs from systemic anaplastic large cell lymphoma (sALCL) in cell biological behavior, clinical features, treatment, and outcome. PC-ALCL has been reported to rarely transition into sALCL, but the underlying mechanism is not clear. Here we report such a case with certain characteristics that shed light on this.

Herein, we report a 43-year-old male with symptoms of a skin nodule and histologically confirmed PC-ALCL with high expression of Ki-67. After three months of observation, two skin nodules re-appeared with muscle layer involvement and was histologically confirmed as sALCL. Seventeen months after receiving six cycles of CHOP regimen, the patient had pain in the chest and back, cough, shortness of breath, and night sweats. This was confirmed as relapse of sALCL by immunohistochemistry and several organs, such as the lung were involved as shown by positron emission tomography/computed tomography. After four cycles of DICE plus chidamide regimens followed by auto-hematopoietic stem cell transplantation (ASCT), complete remission (CR) duration was achieved for twelve months while the patient was on maintenance with chidamide (20 mg) pills.

This case had significantly high expression of Ki-67 when diagnosed as PC-ALCL initially and then transitioned into sALCL, which is rare. Auto-ASCT combined with demethylation drugs effectively maintained CR and prolonged progression free survival.

Mature T-cell and natural killer (NK)-cell neoplasms (MTNKNs) are a highly heterogeneous group of lymphomas that represent 10-15 % of lymphoid neoplasms and have usually an aggressive behavior. Diagnosis can be challenging due to their overlapping clinical, histological and immunophenotypic features. Genetic data are not a routine component of the diagnostic algorithm for most MTNKNs. Indeed, unlike B-cell lymphomas, the genomic landscape of MTNKNs is not fully understood. Only few characteristic rearrangements can be easily identified with conventional cytogenetic methods and are an integral part of the diagnostic criteria, for instance the t(14;14)/inv(14) or t(X;14) abnormality harbored by 95 % of patients with T-cell prolymphocytic leukemia, or the ALK gene translocation observed in some forms of anaplastic large cell lymphoma. However, advances in molecular and cytogenetic techniques have brought new insights into MTNKN pathogenesis. Several recurrent genetic alterations have been identified, such as chromosomal losses involving tumor suppressor genes (SETD2, CDKN2A, TP53) and gains involving oncogenes (MYC), activating mutations in signaling pathways (JAK-STAT, RAS), and epigenetic dysregulation, that have improved our understanding of these pathologies. This work provides an overview of the cytogenetics knowledge in MTNKNs in the context of the new World Health Organization classification and the International Consensus Classification of hematolymphoid tumors. It describes key genetic alterations and their clinical implications. It also proposes recommendations on cytogenetic methods for MTNKN diagnosis.