Background: The addition of CPT-11 to 5FU/leucovorin resulted in survival benefit in patients with advanced colorectal cancer suggesting that this combination could be used successfully in the adjuvant setting. We studied the toxicity profile of postoperatively administered CPT-11 plus leucovorin (LV)-modulated 5FU and radiotherapy in patients with rectal cancer.
Patients and methods: Thirty-seven patients with Dukes' B2 and C rectal adenocarcinoma were treated with CPT-11, 80 mg/m2 ii.v. over 90 minutes followed by LV 200 mg/m2 over 2 hours and 5FU 450 mg/m2 i.v.-bolus weekly for 4 weeks followed by a 2-week rest period. One cycle included 4 infusions. The first cycle of chemotherapy was followed by pelvic radiation to a total dose of 45 Gy to the whole pelvis and a boost of 5 Gy to the tumor bed. 5FU was administered daily as a rapid infusion during the first 3 as well as the last 3 days of radiotherapy. CPT-11 plus LV-modulated 5FU was continued for a total of 6 cycles or consent withdrawal.
Results: The main toxicity was reversible diarrhea (grade 3 and 4) in 9 (26%) patients during chemotherapy and in 3 (9%) patients during chemoradiotherapy. Furthermore, grade 3 leucopenia in 2 (6%) and 1 (3%) patient was observed during chemotherapy and chemoradiotherapy, respectively.
Conclusion: This study provides evidence that adjuvant therapy using CPT-11 plus LV modulated 5FU and radiotherapy can be used in patients with rectal cancer.