Long-term oncological outcomes after local excision of T1 rectal cancer

Background A growing proportion of patients with early rectal cancer is treated by local excision only. The aim of this study was to evaluate long-term oncological outcomes and the impact of local recurrence on overall survival for surgical local excision in pT1 rectal cancer. Methods Patients who only underwent local excision for pT1 rectal cancer between 1997 and 2014 in two Dutch tertiary referral hospitals were included in this retrospective cohort study. The primary outcome was the local recurrence rate. Secondary outcomes were distant recurrence, overall survival and the impact of local recurrence on overall survival. Results A total of 150 patients (mean age 68.5 +/- 10.7 years, 57.3% males) were included in the study. Median length of follow-up was 58.9 months (range 6-176 months). Local recurrence occurred in 22.7% (n = 34) of the patients, with a median time to local recurrence of 11.1 months (range 2.3-82.6 months). The vast majority of local recurrences were located in the lumen. Five-year overall survival was 82.0%, and landmark analyses showed that local recurrence significantly impacted overall survival at 6 and 36 months of follow-up (6 months, p = 0.034, 36 months, p = 0.036). Conclusions Local recurrence rates after local excision of early rectal cancer can be substantial and may impact overall survival. Therefore, clinical decision-making should be based on patient- and tumour characteristics and should incorporate patient preferences.