Anal cancer treated with radio-chemotherapy: correlation between length of treatment interruption and outcome

The purpose of this study was the evaluation of the feasibility and outcome of definitive radio-chemotherapy without split-course technique but with individualised short treatment interruption in anal cancer patients. Between 1993 and 2008, 101 patients with anal cancer were treated in our institution with definitive radio-chemotherapy with individualised short treatment interruptions. Treatment was halted independent of dose in case of acute grade 3 toxicities and started again until improvement. Short interruption was defined as completing treatment without exceeding six cumulative treatment days beyond a scheduled plan; otherwise, it was defined as prolonged interruption. Median overall treatment time was 47 days corresponding to an interruption of six cumulative treatment days. Fifty-one patients (50%) had treatment interruption of a parts per thousand currency sign6 days. No acute grade 4 toxicities were observed. One fatality occurred during treatment due to ileus-like symptoms according to acute grade 5 toxicity. After a median follow-up of 56 months, the 5-year actuarial rates for local control comparing patients with short vs. prolonged treatment interruption were 78% vs. 81% (p = 0.904) and, for colostomy-free survival, 83% vs. 85% (p = 0.784), respectively. Definitive radio-chemotherapy with short individualised treatment interruption shows high local control and colostomy-free survival rates.