| Summary: | Cutaneous sweat gland tumors are a subset of adnexal neoplasms that derive or differentiate into the sweat apparatus. Their great diversity, rarity, and complex terminology make their pathological diagnosis challenging. Recent findings have revealed a wide spectrum of oncogenic drivers, several of which are of diagnostic interest for pathologists. Most of these molecular alterations are represented by gene fusions, which are shared with other homologous neoplasms occurring in organs containing exocrine glands, such as salivary and breast glands, which show similarities to the sweat apparatus. This review aims to provide a synthesis of the most recent immunohistochemical and molecular markers used for the diagnosis of sweat gland tumors and to highlight their relationship with similar tumors in other organs. It will cover adenoid cystic carcinoma (<i>NFIB</i>, <i>MYB,</i> and <i>MYBL1</i> fusion), cutaneous mixed tumor (<i>PLAG1</i> fusion), cylindroma and spiradenoma and their carcinomas thereof (NF-κB activation through <i>CYLD</i> inactivation or <i>ALKP1</i> hotspot mutation), hidradenoma and hidradenocarcinoma (<i>MAML2</i> fusion), myoepithelioma (<i>EWSR1</i> and <i>FUS</i> fusion), poroma and porocarcinoma (<i>YAP1</i>, <i>MAML2,</i> and <i>NUTM1</i> fusion), secretory carcinoma (<i>ETV6</i>, <i>NTRK3</i> fusion), tubular adenoma and syringo-cystadenoma papilliferum (<i>HRAS</i> and <i>BRAF</i> activating mutations). Sweat gland tumors for which there are no known molecular abnormalities will also be briefly discussed, as well as potential future developments.
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