Human leukocyte antigens and multiple basal cell carcinomas.

This study presents data on human leukocyte antigen (HLA) phenotypes of 49 unrelated patients with multiple basal cell carcinomas (five or more BCC). Previous investigators noted an association with HLA-DR1 and a negative association with HLA-DR4. However, the previously found association was weak. HLA typing for class I (HLA-A, -B, -C) and class II antigens (HLA-DR, -DQ) was done from acid citrate dextrose (ACD)-stabilized peripheral blood using the modified lymphocytotoxicity test after T/B cell separation by immunobeads. Antigen frequencies of the patient group were compared to those of healthy individuals of a local German population (n = 716). Chi-square test and Fisher's exact test were used for statistical evaluation. While a significant association with HLA-DR1 was not observed in our study, we were able to confirm a significant decrease of HLA-DR4 in the patient group (12.2% versus 25.1%; p < 0.05; relative risk, RR, 0.48). In addition, HLA-Cw7 was significantly increased in the patient group (61.2% versus 40.8%; p < 0.01; RR, 2.29). In a subgroup of patients with multiple BCC located on the trunk (n = 25), the negative association with HLA-DR4 was even stronger (4% versus 25.1%; p < 0.02; RR, 0.12), whereas HLA-Cw7 was not significant (60.0% versus 40.8%; p = 0.06). Our results showed decreased frequencies of HLA-DR4 and increased frequencies of HLA-Cw7 in cases of multiple BCC, although statistical evaluation revealed only a weak association. This might be due to possible heterogeneity in this disease, e.g., BCC of the trunk versus BCC of the face, or any other cofactors.(ABSTRACT TRUNCATED AT 250 WORDS)