Metastatic Microcystic Adnexal Carcinoma with DNA Sequencing Results and Response to Systemic Antineoplastic Chemotherapy.

Microcystic adnexal carcinoma (MAC) is a rare cutaneous malignancy. Due to its rarity, the molecular characteristics and treatment for metastatic MAC remain undefined. Here we present, as far as we are aware, the first case of metastatic MAC with DNA sequencing results indicating a mutation in TP53 and chromosomal losses in cyclin dependent kinase inhibitor 2A (CDKN2A) and cyclin dependent kinase inhibitor 2B (CDKN2B). In addition, this is the first case of metastatic MAC with a documented objective response to systemic antineoplastic chemotherapy (carboplatin and paclitaxel) confirmed by positron emission tomography/computed tomography. Our case increases the very limited medical knowledge of this rare disease.