Peripheral leucocyte count variations in rectal cancer treatment.

AIM: Mortality after curative surgery for rectal cancer is increased if surgery is not performed within a week of completed short course radiotherapy. A link to the suppression of leucocytes after neoadjuvant radiotherapy has been suggested. This study investigates the effects of radiotherapy on peripheral leucocyte counts, complications and survival. METHOD: Patient data variables from a retrospective database (Local and National Swedish Registries) of a total of 926 consecutive patients treated for rectal cancer disease at two surgical units (1993-2004) were analysed for leucocyte counts and mortality. In all 310 patients received radiotherapy. Mean follow-up time was 2.8 years. RESULTS: There was a marked suppression of leucocytes in the irradiated groups coupled with a reduction in leucocyte response to surgery (p<0.05) compared to non-irradiated patients. Long course radiotherapy resulted in a better postoperative leucocyte response. Irradiated patients with a low post/preoperative leucocyte ratio had higher complication rates. No association between leucocyte response and survival was seen in the irradiated group. CONCLUSIONS: Postoperative leucocytosis is impaired after neoadjuvant radiotherapy, independent of latency period to surgery. Irradiated patients with a suppression of leucocyte response had significantly higher complication rates. The true extent of survival could not be measured in radiotherapy groups due to the short median follow-up period. (Less)