Chromosomes in Noninvasive Papillary Carcinoma of the Bladder

Noninvasive papillary carcinoma of the bladder has the apparent potential to progress in a matter of months or years to invasive cancer. To identify this malignant potential a cytogenetic study was carried out on nine tumors. The results were then compared with similar studies in 11 invasive tumors. In the seven cases of noninvasive papillary carcinoma suitable for analysis, five karyotypic abnormalities were noted; at least four of these were present in each tumor. Coupled with these karyotypic irregularities were marker chromosomes and aneuploidy constituting a triad common to invasive carcinoma of the bladder. These genetic changes precede histologic evidence of invasiveness but support the clinical concept that noninvasive papillary carcinoma is a stage in the development of invasive carcinoma.