Randomized trial of oral adjuvant razoxane (ICRF 159) in resectable colorectal cancer: five-year follow-up.

Razoxane is one of the few agents which has shown activity in the treatment of advanced colorectal cancer. The drug has therefore been evaluated in a prospective randomized controlled trial as an adjuvant to surgery for resectable colorectal cancer. The results to median follow-up of 5 years are reported here. Accrual has ceased and a total of 272 patients entered the trial (133 control, 139 treatment). Treated patients received razoxane postoperatively on a continuous, long-term basis while control patients received identical clinical care but no adjuvant chemotherapy. Analysis of the results shows a significant prolongation of the time to recurrence for Dukes' C patients. All other groups including the overall analysis show no benefit although there is a consistent trend in favour of the treated patients except in Dukes' group 'D'. Razoxane is tolerated well by patients and causes minimal side-effects. However acute leukaemia occurred in three patients (2.45 per cent) after prolonged exposure to the drug and further evaluation should be in patients who are at high risk of developing recurrent cancer, in whom such a risk may be acceptable. It is concluded that razoxane is suitable for further evaluation in colorectal cancer and for incorporation into combination chemotherapy regimens.