Status of prezygotic chromosome lesions in relation to cancer.

There are currently three recognized prezygotic chromosome defects that are associated with specific cancers. These are a deletion of band 13q14 with retinoblastoma, deletion of band 11p13 with Wilms' tumor associated with aniridia, and a reciprocal translocation of chromosomes 3 and 8 with clear cell cancer of the kidney. The two deletions have been assumed to be variants of the hereditary subgroup of tumors. There are many obvious similarities between retinoblastoma associated with deletion of 13q13 and Wilms'-aniridia associated with deletion of 11p13, but there are also significant disparities. Each time a deletion of 13q14 has been found it is associated with a retinoblastoma, while deletions of 11p13 have been associated with nephroblastoma in only 4 of 11 cases. When bilateral disease occurs it is usually seen simultaneously in both eyes with retinoblastoma, but with bilateral nephroblastoma the appearance of the first and second tumors is separated by a year or more. These disparities indicated the possibility that more than one etiologic mechanism may operate even within this group of specific chromosomal mutations associated with specific tumors.