Swiss adjuvant trial (OSAKO 06/74) with chlorambucil, methotrexate, and 5-fluorouracil plus BCG in node-negative breast cancer patients: nine-year results.

Between 1974 and 1977, a total of 254 patients with stages T1-3a, N0-1, and M0 operable breast cancer (node negative and node positive, stratified) were randomized to either modified radical mastectomy alone or the same surgery and adjuvant chlorambucil, methotrexate, 5-fluorouracil (LMF) plus BCG. After a median follow-up of 9 years (January 1985), we concluded that LMF plus BCG significantly increased relapse-free survival (RFS) in 240 fully evaluated patients, especially postmenopausal women. This gain in RFS ceased to transform into a gain in overall survival (OAS) after 7 years of median follow-up for the whole patient group. In the 122 node-negative patients studied, LMF plus BCG produced a marked increase in RFS up to the fifth year and in OAS up to 8 years after initial surgery, thus prolonging significantly the median disease-free interval compared with surgical control patients. This trend favoring LMF plus BCG-treated patients continues. Although median time to first relapse and to generalized disease were increased in relapsing patients by LMF plus BCG, the subsequent intervals from local relapse to distant disease and from distant metastases to death were equal for both treatment regimens. Subjective and objective acute toxicity from LMF plus BCG was mild. At 9 years of median follow-up, fewer second tumors were noted in the node-negative group receiving LMF plus BCG than in surgical controls.