The origin of invasive carcinoma of the bladder.

One-hundred and four consecutive cases of invasive bladder carcinoma were studied. Twenty of the 104 cases had a history of papillary neoplasms of the bladder while the remaining 84 cases did not. Further, 22 of the 104 cases had cystoscopies, months to years prior to the diagnosis of invasive bladder carcinoma, which documented the absence of previous papillary neoplasms of the bladder. Therefore, this study suggests that papillary neoplasms of the bladder may not be the most common precursor of invasive bladder carcinoma. Consequently, vigorously attacking the highly visible papillary neoplasms of the bladder may not be as fruitful in preventing invasive bladder carcinoma as attempting to identify the presence of other less visible nonpapillary lesions which may be the most frequent precursors of invasive bladder carcinoma.