HLA typing in familial testicular cancer

Support is given to the theory of genetic influence in the etiology and pathogenesis of testicular germ cell tumors by the report of four new familial clusters of testicular cancer. One pair of brothers both afflicted with seminoma underwent HLA typing and they were shown to share one complete haplotype. A review of 119 families of the literature with aggregation of germ cell tumors is given. The evaluation of eight previously reported familial clusters of germ cell tumors with HLA-typing results in conjunction with the present case shows a haplotype sharing in all cases which is more than expected. This finding is another piece of evidence for the theory of genetic anticipation of germ cell tumors.