Successful Treatment of HER-2-Positive Metastatic Apocrine Carcinoma of the Skin with Lapatinib and Capecitabine

© 2012 The Authors. doi: 10.2340/00015555-1354 Journal Compilation © 2012 Acta Dermato-Venereologica. ISSN 0001-5555 Primary cutaneous apocrine carcinoma (AC) is a rare and highly aggressive cutaneous adenocarcinoma. In general, most cutaneous AC occurs in the axilla and it is more common in middle-age women (1). Complete remission by chemotherapy is uncommon and median survival was only 2 years for patients with Bloom-Richardson grade 3 tumours (2). HER-2 is a 1260-amino-acid transmembrane protein with tyrosine kinase that plays a central role in cell differentiation, adhesion and motility (3). In the treatment of breast cancer, HER-2 signal inhibitors, such as the humanized monoclonal antibody trastuzumab and the small molecule tyrosine kinase inhibitor lapatinib, have been used as a standard therapy for HER-2 overexpressing metastatic tumour (4). Moreover, several reports have indicated that the apocrine subtype of breast cancer consistently overexpressed HER-2 (5). Interestingly, AC has a marked histological similarity to the apocrine subtype of breast cancer, including immunohistochemistry (6). Therefore, we hypothesized that a HER-2 signal inhibitor, such as lapatinib, can be effective for HER-2 overexpressing metastatic AC. We report here a patient with a metastatic AC showing a complete remission following the administration of lapatinib with capecitabine. To our knowledge, this is the first case report describing the successful treatment of metastatic AC with HER-2 signal inhibitors.