Late toxicity after short course preoperative radiotherapy and total mesorectal excision for resectable rectal cancer

The late toxicity of short-course preoperative radiotherapy (SCPRT) after total mesorectal excision (TME) in resectable rectal cancer has not been adequately documented. The acute toxicity in a series of 176 consecutive patients has been previously reported. In this study, the late toxicity in the same cohort is presented.

Side-effects occurring more than 3 months after the start of SCPRT were graded using the EORTC/RTOG late radiation toxicity system. We performed multivariate analysis to identify associated factors.

Of 176 patients, 15 died within 3 months of SCPRT and five patients were lost to follow-up. One hundred and fifty-six patients were assessable at a median follow-up interval of 41 months: severe (grade 3-4) toxicity was seen in 20 patients (13%), of which 13 were gastrointestinal (8%); three urological (2%); three thromboembolic (2%), and one musculoskeletal (1%). On multivariate analysis, abdomino-perineal (AP) resection (P < 0.02) was associated with a lower risk of grade 3-4 toxicity.

In this retrospective study, the rate of late grade 3-4 toxicity after SCPRT and TME was 13%. Although AP resection seems to be associated with a lower incidence of late toxicity, this could be counterbalanced by the impact of a stoma on quality of life. These factors should be considered when determining the optimal management of resectable rectal cancers.