Comut Erdem, Karstarli Bakay Ozge S, Demirkan Nese Calli
Faculty of Medicine, Department of Pathology, Pamukkale University, Denizli, 20000, Turkey.
Faculty of Medicine, Department of Dermatology, Pamukkale University, Denizli, 20000, Turkey.
BMC Cancer. 2025 Feb 25;25(1):336. doi: 10.1186/s12885-025-13706-y.
Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine skin carcinoma. The pathogenesis involves Merkel cell polyomavirus (MCPyV) and ultraviolet radiation exposure. Studies on MCC in Turkey are scarce, with essential data on local etiopathogenic and prognostic factors still lacking. We aimed to analyze the clinical and histopathologic features, biomarkers, and to evaluate these findings alongside Turkish literature to infer the etiopathogenesis, prognosis, and possible treatment options for the disease.
We analyzed the clinicopathologic features of 7 MCC patients diagnosed at the Pathology Department of Pamukkale University between 2003 and 2024 in this retrospective study. Clinical data was retrieved from the hospital's electronic records. Formalin-fixed, paraffin-embedded tumor specimens stained with hematoxylin-eosin were examined microscopically. MCPyV, Retinoblastoma 1 (RB1), p53, PRAME, PD-L1, and MMR proteins were evaluated immunohistochemically. Research on MCC from Turkey was sourced from Turkish databases (ULAKBIM, Turkiye Atif Dizini, DergiPark, Turk Medline) and international databases (Pubmed, Google Scholar, Scopus, Embase). The literature review identified original research, case reports, theses, and conference presentations.
The patients in our series, all aged over 50 (mean age 76.1 ± 14.8), with a slight predominance of one gender (F: M = 1.33:1). During a mean follow-up of 16.1 months, 42.9% (3/7) had lymph node metastases, and 57.1% (4/7) showed distant metastases. PRAME was positive in 42.9% of the cases (3/7). The total number of MCC cases reported from Turkey was estimated at 227 ± 46, with MCPyV status available in a subset, showing a positivity rate of 70.3%. PD-L1 expression was observed in the tumor microenvironment in 55% of virus-positive MCC cases from Turkey.
The 9% incidence of gluteal localization in Turkish MCC cases, considering its geographical significance, is noteworthy. Notably, all MCC cases from Turkey in which microsatellite instability status has been assessed were found to be microsatellite stable. PRAME should be investigated in larger series for its potential role in the shared oncogenic pathways of MCC.
默克尔细胞癌（MCC）是一种罕见的侵袭性神经内分泌皮肤癌。其发病机制涉及默克尔细胞多瘤病毒（MCPyV）和紫外线辐射暴露。土耳其关于MCC的研究较少，仍缺乏有关局部病因和预后因素的重要数据。我们旨在分析其临床和组织病理学特征、生物标志物，并结合土耳其文献评估这些发现，以推断该疾病的病因、预后及可能的治疗方案。
在这项回顾性研究中，我们分析了2003年至2024年期间在棉花堡大学病理科诊断的7例MCC患者的临床病理特征。临床数据从医院电子记录中获取。对苏木精-伊红染色的福尔马林固定石蜡包埋肿瘤标本进行显微镜检查。免疫组织化学评估MCPyV、视网膜母细胞瘤1（RB1）、p53、PRAME、PD-L1和错配修复（MMR）蛋白。来自土耳其的MCC研究来自土耳其数据库（ULAKBIM、土耳其文摘索引、DergiPark、土耳其医学索引）和国际数据库（PubMed、谷歌学术、Scopus、Embase）。文献综述确定了原始研究、病例报告、论文和会议报告。
我们系列中的患者均年龄超过50岁（平均年龄76.1±14.8岁），女性略占优势（女：男 = 1.33:1）。在平均16.1个月的随访期间，42.9%（3/7）有淋巴结转移，57.1%（4/7）有远处转移。42.9%的病例（3/7）PRAME呈阳性。据估计，土耳其报告的MCC病例总数为227±46例，部分病例有MCPyV状态信息，阳性率为70.3%。在土耳其病毒阳性的MCC病例中，55%在肿瘤微环境中观察到PD-L1表达。
考虑到其地理意义，土耳其MCC病例中9%的臀部分布率值得关注。值得注意的是，在土耳其所有已评估微卫星不稳定性状态的MCC病例中，均发现为微卫星稳定。PRAME在MCC共同致癌途径中的潜在作用应在更大系列中进行研究。
