Reevaluation of Preoperative Chemoradiotherapy for Clinical T3 Lower Rectal Cancer: A Multicenter Collaborative Retrospective Clinical Study

This study aimed to re-evaluate the usefulness of preoperative chemoradiotherapy for clinical T3 lower rectal cancers without lateral lymph node metastasis.

Between 2010 and 2014, 132 patients with clinical T3 lower rectal cancer without lateral lymph node metastasis, 80 years of age or younger, who underwent curative resection at four Jikei University Hospitals were enrolled into this retrospective study. Of these, 22 patients received chemoradiotherapy (CRT) before surgery, 16 patients received intensive chemotherapy after surgery without preoperative CRT, and 94 patients underwent neither preoperative CRT nor intensive chemotherapy after surgery including 47 patients with postoperative oral chemotherapy for pathological diagnosis of stage III.

The 3-year disease-free survival (DFS) of the 22 patients who received preoperative CRT was 95.5%, whereas that of the 94 patients who received neither preoperative CRT nor intensive chemotherapy was 72.0% (p=0.024). However, there was no significant difference in 5-year DFS between the two groups. No significant difference was identified in DFS between the 22 patients who received preoperative CRT and the 16 patients who received intensive chemotherapy after surgery without preoperative CRT.

Intensive chemotherapy after surgery seems to yield a similar prognosis to preoperative CRT in patients with clinical T3 lower rectal cancer without lateral lymph node metastasis.