[HLA and susceptibility to malignancies]

From the large amount of data pertaining to a possible relationship between MHC and susceptibility to malignancies in humans, some significant findings emerge. 1. In population studies, HLA-A2 in ALL and A1 in Hodgkin's disease are observed significantly increased in frequency in comparison to the normal controls. Some significant associations with an HLA phenotype are also observed in several cancers. 2. HLA genotyping of familial cases of Hodgkin's disease, with multiplex affected sibs, lead to the conclusions that an excess of HLA identical pairs are observed among the patients. This could indicate a linkage between the susceptibility gene and the HLA region. Another linkage might exist with familial malignant melanoma fitting with a dominant mode of transmission of the trait. These facts strongly support the role of the MHC among the polyfactorial and polygenic determinism of some malignancies. The mechanisms are discussed.