Short- and long-term outcomes of local excision with adjuvant radiotherapy in high-risk T1 rectal cancer patients.

Purpose: The standard of care for early rectal cancer is radical surgery; however, it carries high postoperative morbidity. This study aimed to assess the short-term and oncological outcomes of local excision and adjuvant radiotherapy in patients with high-risk pathological stage (p) T1 rectal cancer.

Methods: Fifty-five patients underwent local excision with adjuvant radiotherapy or radical resection for high-risk T1 rectal cancer. Patients with adenocarcinoma within 10 cm from the anal verge; pT1 with high-risk features (grade 3-4); a tumor size of ≥3 cm; a positive margin; a lymphovascular or perineural invasion; or a submucosal invasion depth of ≥SM2 were included.

Results: The rates of postoperative complications and stoma formation were higher in the radical surgery group (P = 0.021 and P = 0.003, respectively). No significant differences were observed in the overall survival and disease-free survival (DFS) between the 2 groups (P = 0.301 and P = 0.076, respectively). Vascular invasion was a significantly poor prognostic factor for DFS (P = 0.033). The presence of 3 or more high-risk features was associated with a poor DFS (P = 0.002).

Conclusion: Local excision with adjuvant radiotherapy significantly reduces the risk of complications and stoma formation. It is also an alternative option for patients with fewer than 3 high-risk features.