The consequences of misinterpreting benign scalp masses masquerading a malignant recurrence

Hidradenocarcinoma is an exceptionally rare malignancy of skin appendages, often posing significant diagnostic challenges. We report the case of a young woman presenting with a right-sided neck swelling, five months after excision of a scalp mass that was initially diagnosed as a benign nodular hidradenoma. Biopsy of the neck lesion reported as metastatic carcinoma, prompting a re-evaluation of the scalp specimen. A second diagnosis of hidradenocarcinoma was made. The patient underwent a modified radical neck dissection followed by adjuvant radiotherapy. This case underscores the importance of revisiting histopathological diagnoses in cases of regional malignancy and highlights the critical role of a multidisciplinary approach in managing rare skin appendage tumours.