Levamisole in primary breast cancer. A controlled study in conjunction with l-phenylalanine mustard

Between September 1976 and May 1980, 135 patients with operable breast cancer and positive axillary nodes received l-phenylalanine mustard, adjunct to surgery, 0.15 mg/kg for five days, six weekly, and were randomised prospectively to levamisole 150 mg for three days, two weekly, or a placebo. Treatment was continued for two years or until evidence of treatment failure, whichever was the sooner. At 4 1/2 years, for all patients, there was no significant difference between the two groups (P = 0.09), but in a subgroup of women less than or equal to 50 with 1-3 positive nodes, levamisole had a negative effect (P = 0.05). Although an analysis of the same age group, independent of the nodal status, did not reach significance, there was a trend in favor of placebo (P = 0.08) which was also apparent in premenopausal women (P = 0.15). In postmenopausal patients, however, and in those with more advanced disease with four or more positive nodes, although the results also failed to reach significance the trend in these subgroups favored levamisole. The results of this study suggest that levamisole has no place in the primary therapy of breast cancer in younger women and those with more favorable disease. The value of this agent in older patients and those with more advanced primary disease, remains unproven, but the favorable trends are in accord with a number of other studies with levamisole in metastatic breast and resectable lung cancer. Retrospective analysis confined to those women who received 75% or more of the total dose of l-phenylalanine mustard showed no evidence for a dose-responsive effect of adjuvant chemotherapy on the described pattern of results.