A randomised comparison of photons and 15 MeV neutrons for the treatment of carcinoma of the bladder.

108 patients with T2 or T3 carcinoma of the bladder were randomised to receive either photon therapy or low- or high-dose 15 MeV neutrons. Fifty-nine patients received photon treatment, 20 low-dose neutrons (LDN) and 20 high-dose neutrons (HDN). Eight patients received a combination of photon and neutron therapy, due to machine breakdown, and one patient received only one exposure, due to intercurrent illness. The three-year survival for all groups was 43% but there was no difference in survival between the treatment groups. The complication rate in the photon group was low--minor 3%, major 5%. The complication rates in the neutron groups were higher--LDN 30% and 15% respectively, HDN 15% and 10% and combined 25% and 37%. Only six patients died of complications related to therapy--photons 2, LDN 1, HDN 1, combined 2. No therapeutic gain for neutron therapy has been found in this study.