Nonpapillary lesions of the urinary bladder: a retrospective study.

The histological and clinical features of nonpapillary bladder lesions in 53 patients are described. There were 8 patients (Group A) with atypical hyperplasia and/or carcinoma in situ, 16 patients (Group B) with nonpapillary invasive transitional cell carcinoma, and 29 patients (Group C) with nonpapillary bladder lesions and synchronous or metachronous papillary tumors. These lesions were usually represented clinically by irritative urinary symptoms, such as frequency, urgency, dysuria and hematuria. In 34 of the 53 patients (64.1%), bladder lesions were invisible, i.e., not seen on cystoscopic examinations, and were diagnosed by histological examination of random biopsy specimens or by cytological examination of the urine. The 5-yr survival rates for Groups A, B and C patients were 100, 30.2 and 80.9%, respectively, while the disease progression rate during the same period of time was 72.6, 69.8 and 26.8%, respectively. The significance of the invisible flat lesions of the bladder that are considered to give rise to most types of invasive metastasizing tumors is reviewed and discussed.