HLA antigens in malignant melanoma patients.

One hundred and forty melanoma patients, divided in 2 groups, i.e., patients with clinical evidence of melanoma and patients with no clinical evidence of melanoma, were typed for HLA-A, -B and -C antigens and compared with 340 to 905 (according to each HLA antigen examined) healthy adult blood donors. Overall, a highly significant increase in HLA-B40 antigen (p = 5.6 x 10(-7)) and a decrease in HLA-BW35 (p = 1.6 x 10(-4)) was observed. No relevant difference was found between the 2 groups. Moreover, an unexpected excess of HLA blanks was observed at both A and B loci in the first group (p = 1.3 x 10(-2) and p = 3.3 x 10(-6), respectively) and only at the B locus in the second (p = 1.2 x 10(-2)), when the patients were compared to 288 healthy individuals HLA typed at the same time and with the same HLA antisera as the patients. The increase in HLA blanks in melanoma patients deserves further investigation to ascertain whether it may be due to the tumor not yet surgically removed or may be referred to technical pitfalls.