Human leukocyte antigens (HLA) are cell surface glycoproteins that have a significant role in the immune system. In some cancers, changes in major histocompatibility complex (MHC) class I and II expression, usually a reduction or loss of these molecules, appear to provide a mechanism whereby tumor cells may escape host immunity. HLA analysis in patients with advanced adenocarcinoma of the prostate revealed the antigens with the highest relative risk factors as DRw52, DRw53, Bw73, DR2, and B5(51). As a result, determination of HLA haplotypes may prove to be useful in determining the men with a higher risk of developing prostate cancer. (C) 1994 Wiley-Liss, Inc.