[Histological effect of preoperative irradiation in bladder cancer].

Forty-seven patients with high grade invasive bladder cancer were treated with preoperative radiation therapy (910 rad by fast neutron or 3000 rad by X-ray for two weeks) followed by radical cystectomy and urinary diversion. Stage down effect was observed in 32% of patients when comparison was made between the clinical and pathological stages. Those who showed stage down effect had better prognosis when compared those without it. Histopathological effect of Grade 2B or Grade 3, according to the criteria described by Ohboshi and Shimosato, was noticed in 49% of the patients. Five year survival was as follows: 100% (PT0, PTis), 75% (PT1), 100% (PT2), 47% (PT3), 0% (PT4). These results clearly showed the improvement of prognosis compared to the historical control.