Outcomes of Local Excision plus Chemoradiotherapy in Patients with T1 Rectal Cancer.

Objective: The National Comprehensive Cancer Network (NCCN) guidelines recommend local excision and observation as standard treatment for selected patients with clinical T1N0M0 rectal cancer. In patients with pathological T1 (pT1) rectal cancer who received local excision, the local recurrence rate is at least 10%. We studied oncological outcomes in patients with pT1 rectal cancer who received chemoradiotherapy (CRT) after local excision.

Methods: Local excision was performed in 65 patients with clinical T1N0M0 rectal cancer (≤8 cm from the anal verge, tumor size < 30 mm, well or moderately differentiated adenocarcinoma). The patients received CRT (40 or 45 Gy in 1.8-2.0 fractions with concurrent oral UFT [tegafur/uracil] or S-1 [tegafur/gimeracil/ote-racil]) after confirmation of pT1 and negative margins.

Results: Patients who had pT2 cancer or who did not provide informed consent were excluded. The remaining 50 patients additionally received CRT. The CRT was completed in 48 patients (96%). The median follow-up period was 71 months. Local recurrence occurred in 1 patient (2%). Distant metastases occurred in 3 patients (6%). The 5-year disease-free survival rate was 86%, and the 5-year overall survival rate was 92%.

Conclusions: Our study suggested that multidisciplinary treatment with local excision plus CRT can be used as a treatment option in selected patients with clinical T1N0M0 rectal cancer.