A review of cutaneous apocrine carcinoma: epidemiology, diagnosis, prognosis, and treatment options.

Cutaneous apocrine carcinoma is a rare skin cancer arising from apocrine sweat glands. Disease-specific treatments are required for cutaneous adnexal carcinomas due to their heterogeneous treatment responsiveness. This review reports on the epidemiology, diagnosis, pathological features, surgical management, and use of systemic therapies for cutaneous apocrine carcinoma. Diagnosing cutaneous apocrine carcinoma requires presenting with distinctive pathological features and excluding metastatic adenocarcinomas, particularly breast cancer. Clinical findings are essential to exclude metastatic adenocarcinomas, and immunohistochemistry can be used as an adjunctive tool to rule out other diseases. Wide local excision is the standard treatment for resectable cutaneous apocrine carcinomas. Prophylactic lymphadenectomy should be considered as a treatment option given the high incidence of lymph node metastasis. Generally, cutaneous apocrine carcinomas are resistant to chemotherapy and radiation therapy; however, adjuvant radiotherapy is recommended for high-risk patients. Radiation or systemic therapy is administered to patients with distant metastases or recurrence. The systemic therapeutic options include cytotoxic chemotherapy, hormonal therapy, targeted therapy, and immune checkpoint inhibitors. Given the lack of data on clinical prognosis and standardized treatments, further studies are needed to improve our understanding of cutaneous apocrine carcinomas.