Transient and chronic neurological complications of fast neutron radiation for adenocarcinoma of the prostate

The records of 132 patients participating in clinical trials using fast neutron ( n = 94), mixed neutron and photon ( n = 16), or conventional photon ( n = 22) irradiation for primary management of prostatic cancer were retrospectively reviewed to assess treatment-related neurological complications. With a median follow-up of 14 months (range 1 to 101 months), 31 132 patients (26 neutron, 3 mixed beam, 2 photon) have experienced either sciatica beginning during or shortly after treatment, or diminished bladder or bowel continence that developed at a median time of 6.5 months following treatment. Sciatica responded to oral steroids and was usually self-limited, whereas sphincter dysfunction appears to be permanent. Pre-treatment risk factors for complications included a history of hypertension, diabetes, cigarette smoking or peripheral vascular disease, with 81% of affected patients having one or more risk factors compared with 55% of unaffected patients ( p = 0.01). Seven patients have moderate (5) or severe (2) residual problems, all in the cohorts receiving neutrons ( 6 7 ) or mixed beam therapy ( 1 7 ).