Primary cutaneous apocrine carcinoma: 2 cases and review of the pertinent histologic findings

Primary cutaneous apocrine carcinoma (PCAC) is a rare cutaneous adnexal tumor that presents a diagnostic challenge, with histology and staining mirroring those seen in mammary ductal carcinoma and other adnexal neoplasms. We report the first case, to our knowledge, of PCAC with in-transit metastasis responding to primary radiotherapy as a treatment. We also describe a case of PCAC treated with axillary lymph node dissection, wide local excision, and adjuvant radiotherapy. We hope this review provides greater awareness of this neoplasm in the differential diagnoses of metastatic breast carcinoma, as the prognostic implications may differ significantly.