Adjuvant radiotherapy following total mesorectal excision for stage IIA rectal cancer: is it beneficial?

Purpose: The benefit of adjuvant radiotherapy in patients with stage IIA (T3N0) rectal cancer following total mesorectal excision (TME) is controversial. We evaluated the effect of adjuvant chemoradiotherapy (CRT) versus chemotherapy (CT) alone on the local recurrence and survival of patients with stage IIA rectal cancer after TME.
Methods: Between 1996 and 2004, patients with stage IIA rectal cancer who received adjuvant CT (n = 29) or CRT (n = 122) following TME were enrolled. Oncologic outcomes were compared between groups, and risk factors for local recurrence and overall survival rates were analyzed.
Results: The median follow-up period was 78 months. No significant differences were observed in the 5-year local recurrence (3.4% versus 9.0%; P = 0.348) or 5-year overall survival rates (86.2% versus 80.3%; P = 0.924) between CT and CRT. However, involvement of the circumferential resection margin and age >60 years were associated with adverse oncologic outcomes.
Conclusions: Additional postoperative radiotherapy did not alter local recurrence or survival after TME in patients with stage IIA rectal cancer. Postoperative radiation may be an overtreatment as an adjuvant therapy in patients with stage IIA rectal cancer if they had no other risk factors. However, randomized controlled trials are warranted to confirm this suggestion.