Fifty-three month persistence of ring chromosome in noninvasive bladder carcinoma

In a recurrent noninvasive papillary carcinoma of the bladder cytogenetic analysis by the direct technique was carried out on cystoscopic biopsies obtained at 53 month intervals. Persistent similar karyotypic abnormalities including aneuploidy, and ring and other marker chromosomes, the hallmarks of invasive cancer, were present in both specimens. In the 1973 specimen, DNA banding was identified in 35 per cent of the metaphases and in 56 per cent of the karyotypes. The continuing abnormal chromosomal silhouette of this tumor supports the stemline cell concept for malignancies, even when applied to such relatively benign neoplasms as this noninvasive carcinoma of the bladder.