The addition of low-dose leucovorin to the combination of 5-fluorouracil- levamisole does not improve survival in the adjuvant treatment of Dukes' C colon cancer. IKN Colon Trial Group.
OBJECTIVE
To assess the effect of the addition of leucovorin to the combination of 5-fluorouracil (5-FU)-levamisole on recurrence risk and overall survival in patients after a resection with curative intent of a Dukes' C colon cancer.


METHODS
Five hundred patients with Dukes' C colon cancer were randomly assigned to adjuvant treatment for one year with 5-fluorouracil (450 mg/m2 i.v. weekly) and levamisole (150 mg p.o. every two weeks), the C-group or with leucovorin (20 mg/m2 i.v.), 5-fluorouracil and levamisole, the L-group. The median follow-up for patients still alive is 36 months. Four patients were ineligible because of advanced disease at the time of randomisation.


RESULTS
Sixty percent of the patients have completed all courses of chemotherapy. Of the remaining 40% of the patients who did not complete one-year treatment with chemotherapy, 46% discontinued because of toxic and/or emotional reasons. They were equally divided over both treatment arms. The addition of leucovorin increased toxicity (especially mucositis and conjunctivitis) without a significant increase in treatment withdrawal. Five-year disease-free interval (C-group: 49%, L-group: 46%; log-rank test, P = 0.86) and overall survival (C-group: 55%, L-group: 59%, log-rank test: P = 0.96) were very similar in both treatment arms.


CONCLUSIONS
The addition of low dose leucovorin to the combination of 5-fluorouracil and levamisole in a 12-month adjuvant therapy for curatively resected Dukes' C colon cancer patients does not improve disease-free interval nor overall survival. The addition of leucovorin to the combination of 5-FU levamisole increases toxicity. Therefore leucovorin 5-FU levamisole is not recommended in a 12 months adjuvant regime of Dukes' C colon cancer.
Bleeker
W A
WA
The Comprehensive Cancer Centre North Netherlands, Groningen.
Mulder
N H
NH
Hermans
J
J
Otter
R
R
Plukker
J T
JT
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery*; D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000601:surgery*; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D007978:Levamisole / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D000276:Adjuvants, Immunologic; D007978:Levamisole; D002955:Leucovorin; D005472:Fluorouracil