Leucovorin and 5-fluorouracil versus levamisole and 5-fluorouracil as adjuvant chemotherapy in rectal cancer

Abstract

Purpose: To evaluate the effectiveness of 6-month therapy with leucovorin (LV)+5-fluorouracil (5-FU) versus 12-month therapy with levamisole (LVS)+5-FU, as adjuvant chemotherapy in patients with completely resected Aster-Coller stage B(2) or C(1)/C(2) rectal cancer (RC).

Patients and methods: One hundred and fifty patients with surgically resected RC were enrolled. Seventy patients with stage B(2) and 80 with stage C were randomly assigned to adjuvant chemotherapy with 5-FU+LXx6 months or 5-FU+LVSx12 months. Patient characteristics were equally balanced between the examined groups. Adjuvant chemotherapy consisted of LV 20 mg/m(2) intravenously (i.v.) plus 5-FU 450 mg/m(2) i.v. bolus every week plus LVS tablets 50 mg t.i.dx3 days every 2 weeks for 1 year.

Results: After a median follow up for survivors of 8.7 years (range 1.8-10.5), all of the patients were evaluable. There were no significant differences between the two treatment groups with respect to the recurrence rates (p=0.821). Moreover, there were no significant differences between the two tratment groups in disease-free survival (DFS) (p=0.84) [B(2)(p=0.805) and C (p=0.978)] and overall survival (OS) rates for patients of either stage B(2) or C (p=0.78). Toxicities were more frequent in the 5-FU+LVS versus 5-FU+LV group: myelosuppression (grade 3 leucopenia, 12 versus 4%, p<0.04), diarrhea (grade 0, 60 versus 76%, p<0.02), and liver toxicity (increase of transaminases >3-fold, 12 patients versus 2, p<0.03.). No patient stopped chemotherapy because of toxicity, and there were no treatment-related deaths.

Conclusion: Adjuvant chemotherapy in RC with LV+5-FU for 6 months is equally effective and less toxic than LVS+5-FU for 12 months.