A Case of Basal Cell Carcinoma Arising on the Palm

Abstract

An 88-year-old man had an ostium on his left palm for approximately 20 years. Several months prior to his rst visit, the lesion began to grow quickly ; therefore, he visited our department. At the initial examination, he presented with a 15×12 mm red nodule with a well-dened margin and supercial erosion in the center of the left palm. Histopathology revealed tumor nests comprising basophilic tumor cells connected to the epidermis. No partial skin ulcer or differentiation to the lower part of the follicle was identied. These ndings were characteristic of basal cell carcinoma (BCC). Fissure formation, mucin, and deposition were not observed. The surrounding area was abundant in spindle cells. These ndings suggested benign trichoblastoma (TB). Immunohistochemical analysis revealed that the tumor cells expressed Ber-EP4 and were partially positive for PHLDA-1. Scattered androgen receptor-positive cells were observed, whereas no CK20-positive Merkel cells were found in the nests. These ndings were characteristic of BCC. Based on the comprehensive assessment of the above ndings, we diagnosed the tumor as nodular ulcerative BCC. Cases of BCC on the palm are rare. Skin Research, 18 : 94-98, 2019