Primary Cutaneous Cribriform Tumor with Clinical and Histological Diagnostic Challenges: Case Report and Literature Review of a Rare Skin Neoplasm.

BACKGROUND The skin is the largest organ of the human body and plays a critical role in maintaining homeostasis. It helps regulate body temperature, protects against physical and chemical environmental insults, and serves as a barrier to microbial invasion by acting as a vital interface between the internal body and the external environment. Skin neoplasms encompass a wide variety of tumors. Because they are heterogeneous in their cell of origin, biological behavior, treatment, and prognosis, their classification is often complex and can sometimes mislead clinicians in distinguishing clearly between malignant and benign entities. CASE REPORT In this article, we report the case of a previously healthy man who presented with a solitary subcutaneous left leg skin nodule. After appropriate clinical examination, surgical excision, radiological tests, and pathological analysis, it was ultimately diagnosed as cribriform tumor (previously known as primary cutaneous cribriform carcinoma), an exceedingly rare adnexal skin neoplasm, which has been reported approximately only 50 times in the scientific literature. We describe its clinical features and biological characteristics, and describe the diagnostic procedure and available treatment. Because of the rarity of this tumor and consequently the limited research and available data, diagnosis and treatment can be particularly challenging for histopathologists and clinicians. CONCLUSIONS This article provides additional insights and description of this extremely rare entity, cribriform tumor, contributing to the growing body of evidence and aiding clinicians in avoiding potential misdiagnosis with other malignant or benign skin neoplasms.