Peri-operative heparin: a possible adjuvant to surgery in colo-rectal cancer?

Analysis of data from a randomised trial of adjuvant razoxane involving 603 patients with colo-rectal cancer having curative surgery is reported. The results show that razoxane was ineffective but peri-operative subcutaneous heparin treatment apparently conferred a statistically significant improvement in survival at 5 years, or equivalently a reduction in the risk of death. This beneficial effect is apparent in both razoxane treated and control patients and is not explained by demonstrable differences between heparin and non-heparin treated patients in the distribution of known prognostic factors. Adjustment for these factors slightly increased the apparent magnitude of the beneficial effect.