Microcystic Adnexal Carcinoma of the Nipple

BACKGROUND: Microcystic adnexal carcinoma (MAC) is a rare infiltrative cutaneous tumor, but with its locally aggressive nature, high rate of recurrence, and rare metastatic potential, it is an important clinical entity to consider when faced with a nipple lesion. These tumors are frequently misdiagnosed based on superficial biopsy alone. CASE REPORT: This case of a 15-year-old girl with MAC of the nipple demonstrates the importance of having a high index of suspicion in order to obtain a diagnosis, to determine the extent of disease, and to achieve adequate resection before reconstruction. Close clinical observation is recommended due to the possibility of future recurrences. CONCLUSIONS: Between the confusing nomenclature, indolent course, and inadequacy of superficial biopsy to achieve an accurate diagnosis, MAC is a clinical entity that the plastic surgeon must be aware of in order to facilitate proper diagnosis and treatment.