The outcome of transanal endoscopic microsurgery and adjuvant radiotherapy in patients with high-risk T1 rectal cancer.

[INTRODUCTION] Transanal endoscopic microsurgery (TEM) is considered the technique of choice for adenoma and low-risk T1 rectal cancer. The adequacy of such treatment for high-risk T1 tumours, however, is still controversial. The aim of the study is to evaluate our results with local excision of high-risk T1 cancers.

[AND METHODS] Demographic, clinical data pertaining to patients undergoing TEM for T1 rectal cancer between 1999 and 2015 was retrospectively collected. Long-term outcomes were assessed for the entire cohort. Patients were classified into two groups: favourable and high-risk cancer features.

[RESULTS] Three hundred and fifty-five TEM procedures were recorded in the study period. Forty-three patients were included in the present study. There were 20 females and 23 males, the median age was 69 ± 9. The median tumour distance from the anal verge was 6 cm (range 1-13 cm). Post-operative histopathology showed well/moderately differentiated T1 adenocarcinoma in 30 patients and poorly differentiated in 13. The overall survival for patients with favourable and high-risk features groups were 93.5% and 77%, respectively, while the local recurrence (LR) was 3.5% and 23.1%, respectively. Nine patients with high-risk features received adjuvant radiotherapy; one (11.1%) of them experienced LR.

[CONCLUSIONS] Local excision by TEM augmented by adjuvant radiotherapy may be a feasible alternative for selected patients with high-risk T1 rectal cancer. The addition of radiotherapy seems to decrease the rates of LR.