Sorino Joana, Della Mura Mario, Colagrande Anna, Salzillo Cecilia, Ingravallo Giuseppe, Cazzato Gerardo
Section of Molecular Pathology, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari "Aldo Moro", 70124 Bari, Italy.
Dermatopathology (Basel). 2025 Jan 13;12(1):1. doi: 10.3390/dermatopathology12010001.
Cutaneous squamomelanocytic tumor (SMT) is a very rare cutaneous malignancy, composed of a dual phenotypic population of both malignant melanocytes and keratinocytes, intimately intermingled together. Herein, we report a new case of a SMT occurring in an 82-year-old man, located on the scalp. Histopathology revealed a mixed population consisting of squamous cell carcinoma and melanoma within the same lesion, also confirmed using immunohistochemical staining for high molecular-weight cytokeratins (HMWCKs) and Melan-A. Moreover, to the best of our knowledge, for the first time, we tested SMT for the preferentially expressed antigen in melanoma (PRAME), which revealed a strong and diffuse positivity in the melanocytic component. These tumors need to be distinguished by more frequent collision tumors and colonization. Furthermore, we provide a comprehensive review of the literature, focusing on clinical and histopathological aspects, biological behavior and still-debated, but fascinating histogenesis of this elusive entity.
皮肤鳞状黑素细胞肿瘤（SMT）是一种非常罕见的皮肤恶性肿瘤，由恶性黑素细胞和角质形成细胞这两种具有双重表型的细胞群体紧密混合而成。在此，我们报告一例发生在一名82岁男性头皮上的SMT新病例。组织病理学显示同一病变内存在由鳞状细胞癌和黑色素瘤组成的混合细胞群体，这也通过高分子量细胞角蛋白（HMWCKs）和Melan - A的免疫组织化学染色得到证实。此外，据我们所知，我们首次对SMT检测了黑色素瘤中优先表达的抗原（PRAME），结果显示在黑素细胞成分中呈强而弥漫的阳性。这些肿瘤需要与更常见的碰撞瘤和浸润瘤相鉴别。此外，我们对文献进行了全面综述，重点关注该难以捉摸的实体的临床和组织病理学方面、生物学行为以及仍存在争议但引人入胜的组织发生学。
