Uncommon neoplasms mistakenly diagnosed as hidradenitis suppurativa: Report of three consecutive cases.

Hidradenitis suppurativa (HS) poses diagnostic challenges due to its clinical overlap with various skin conditions and neoplasms, potentially leading to misdiagnoses. The absence of a definitive diagnostic test and infrequent use of histopathology contribute to diagnostic complexities, exacerbated by the recent increased focus on HS. Three cases initially diagnosed and treated as HS underwent clinical work-up and skin biopsies to resolve diagnostic complexities. Initially labeled as HS, the cases revealed a breast carcinoma on axillary ectopic tissue, a cutaneous gamma-delta T-cell lymphoma, and an infiltrating squamous cell carcinoma. Delayed recognition led to misguided therapies and adverse outcomes. This report stresses the need to explore alternative diagnoses for chronic skin nodules with or without ulcerations on the flexures. Timely skin biopsies are crucial for accurate diagnoses. Ongoing clinician education is essential to avoid misdiagnosis in challenging cases, in which histopathology aids in reaching a correct diagnosis.