The Usefulness of CD10 in Distinguishing between Cutaneous Basal Cell Carcinoma and Squamous Cell Carcinoma

Background & Objectives:  CD10 is a cell surface enzyme with metalloendopeptidase activity, also known as Common Acute Lymphoblastic Leukaemia Antigen, which mainly serves as a marker for acute lymphoblastic leukemia (ALL). To date and to the best of our knowledge, only few comparative immunohistochemical studies have assessed CD10 expression in cutaneous epithelial neoplasms. Our goal was to determine whether CD10 can be used in pathologic distinction of cutaneous basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Methods: This study included 27 BCC and 17 SCC cases   immunohistochemically stained for CD10. Cytoplasmic +/- cell membrane staining was considered as positive. Each slide was studied by two pathologists and scored semi- quantitatively as follows: negative (<10%); 1+ (10-50% positive cells); and 2+ (>50% positive cells). Results: The rate of CD10 expression in tumor cells was significantly higher in BCCs in comparison to SCCs. (20/27 vs., 2/17; P <0.0001). Discussion: Our findings suggest CD10 as a useful adjunct marker in distinguishing cutaneous BCC and SCC.