Is postoperative adjuvant chemotherapy necessary in locally advanced rectal cancers after preoperative chemoradiation

Abstract

Materials/Methods: Between 1986 and 2000, 209 patients with tethered or fixed rectal cancers were treated with preoperative chemoradiation according to 3 different schedules. In schedule I, 54 patients were treated with 40 Gy RT plus concurrent 5FU infusion and mitomycin C. In schedule II, 27 patients were treated with “sandwich” chemoradiation: 40 Gy preoperative RT with concurrent 5FU infusion, leucovorin and mitomycin C, and 18 Gy postoperative RT with similar concurrent chemotherapy. The design of both schedules I and II did not include any postoperative adjuvant chemotherapy. In schedule III, 128 patients were treated with 50 Gy preoperative RT concurrent with 5FU infusion, leucovorin and mitomycin C, followed by 5 cycles of postoperative bolus 5FU/leucovorin chemotherapy. After excluding patients with M1 disease and patients in schedules I and II who have received some postoperative chemotherapy off-protocol, 184 patients were available for the analysis. There were 134 males and 50 females. The median age was 62 years (range: 30 – 82 years). There were 141 tethered and 43 fixed rectal cancers. There were 91 low(3–5 cm from the anus), 82 mid(6 –10 cm) and 11 high( 10 cm) rectal cancers. 97 patients had an abdominoperineal resection, 84 patients had an anterior resection, 2 patients had a Hartman’s resection and one patient had an exenteration. The post-chemoradiation TNM stage distribution was as follow: 36 stage 0 (T0N0M0), 52 stage I, 58 stage II, and 38 stage III. 99 patients (in schedule III) received postoperative bolus 5FU/leucovorin chemotherapy and 85 patients did not. 65% (55/88) of stages 0 and I, and 46% (44/96) of stages II and III had received postoperative adjuvant chemotherapy.