The Heterogeneity of Invasive Bladder Carcinoma and Different Responses to Treatment

Abstract

Patients (475) with bladder carcinoma were studied to test the effect of adjuvant radiotherapy (4500 R in 28-32 days) on the surgical management of patients with histological proof of muscle invasion. The patients were randomized to receive radiotherapy or not and an appropriate open operation (more than 85% cystectomy). All patients never completed the protocol. Of those who did, it was almost immediately evident that radiotherapy resulted in apparent destruction of the tumor as determined by pathological examination in 1/3 of the surgical specimens (Po). For several yr no advantage to the radiotherapy group was evident; subsequent follow-up revealed that the Po group was surviving significantly better than the control group. The current analysis, while lacking complete data on all patients, indicates that invasive bladder carcinoma usually is solid and that solid tumors most commonly invade lymphatics and are not radiosensitive. Invasive papillary carcinomas are more commonly radiosensitive and do not invade lymphatics as frequently as solid tumors. Patients with papillary invasive carcinoma who have no lymphatic involvement in the transurethral resection specimen, receive radiotherapy and are Po have a probability of surviving 5 yr in excess of 85%; patients with solid tumor and lymphatic invasion who receive radiotherapy and are P+ have a 20% probability of surviving 5 yr. Invasive bladder carcinomas are exceedingly heterogeneous; examination of the transurethrally resected specimen and the cystectomy specimen provides valuable information concerning the probability of survival. These data provide the basis for testing this hypothesis and for developing therapuetic strategies based on prognostic indicators.