Chromosomes in renal carcinoma with reference to intratumor heterogeneity.

Cytogenetic studies of renal tumors from seven patients were performed (six renal cell carcinomas, one transitional cell carcinoma). Multiple samples were obtained from each tumor as well as one sample from normal tissue. Cultures were established after collagenase disaggregation. From five tumors, two or more cultures were available for chromosome analysis. All tumors were chromosomally abnormal, although some cultures had a normal chromosome complement. Aberrations involving chromosome 3 were seen in four tumors. Two patients had an identical marker chromosome del(3)(p14), suggesting that the breakpoint may be of significance for the development of tumors of the kidney. An extra chromosome 7 was found in four patients. In all four tumors from which two or more tumor cultures were studied, the chromosome constitution showed, besides a primary cytogenetic change, additional clonal abnormalities illustrating intratumoral heterogeneity.