CYTOGENETIC HETEROGENEITY IN A 2ND PRIMARY RADIATION-INDUCED BLADDER-CARCINOMA - 10 KARYOTYPICALLY UNRELATED CLONES

Cytogenetic analysis of a transitional cell carcinoma (TCC) of the bla dder, the tumor having developed 32 years after the patient received p elvic irradiation and interstitial radium implantation for an endometr ial carcinoma, revealed the presence of 10 cytogenetically abnormal, u nrelated clones. Although the tumor was poorly differentiated, all clo nes were pseudo- or near-diploid with rather simple balanced or unbala nced structural rearrangements or both. The chromosomes involved in st ructural changes more than once rr ere chromosomes 8, 9, and 11, which were rearranged in three clones, and chromosomes 3 and 17, both rearr anged in two clones. No previous TCC of the bladder with cytogenetical ly unrelated clones has been reported, nor has any such radiation-indu ced tumor with chromosomal abnormalities been described. The distinct karyotypic and clonal pattern of the case presented here is probably i ndicative of a carcinogenic field effect due to the previous pelvic ir radiation. Postradiation bladder carcinomas thus seem to be distinct c ytogenetically in addition to their known unique etiological and clini cal features. (C) Elsevier Science Inc., 1998