Cutaneous eccrine spiradenoma: Insights into cytomorphological features via fine needle aspiration biopsy and a comprehensive literature review

Eccrine spiradenoma (ES) is an uncommon and benign adnexal tumour originating from sweat glands. The cytological examination of ES poses a diagnostic challenge, as it can be mistaken for various benign and malignant basaloid skin neoplasms. The cytomorphologic features of ES are infrequently documented in existing literature. This study seeks to present a thorough exploration of the cytomorphologic traits associated with ES, accompanied by an analysis of ancillary testing that contribute to the accurate identification of this entity in cytological specimens. Eccrine spiradenoma is infrequently encountered in fine needle aspiration (FNA) cytopathology, and the available literature on its cytomorphologic features is limited. The challenge arises from its similarity to other benign and malignant dermal basaloid neoplasms, emphasizing the critical role of clinicopathologic correlation and immunohistochemical staining in achieving a precise diagnosis.