Soft-tissue sarcoma: neutrons versus photons for post-operative irradiation.

Between November 1980 and June 1981, 14 patients with soft-tissue sarcoma were entered into a prospective randomized trial comparing the efficacy of megavoltage photon irradiation with cyclotron-generated fast neutrons as post-operative adjuvant therapy. It became apparent that patients whose primary tumours had been treated with very wide excision, in particular by compartmental resection, suffered severe late tissue damage when subsequently irradiated with fast neutrons. It was therefore decided to terminate the trial after only 14 patients had been entered. Unacceptable late tissue damage may result from the therapeutic use of fast neutron irradiation when applied in these circumstances.