An evaluation of the effect of vincristine added to cyclophosphamide, 5-fluorouracil, methotrexate, and prednisone in advanced breast cancer.

A multi-institutional randomized clinical trial was carried out to evaluate the effect of vincristine (V) added to cyclophosphamide, methotrexate, 5-fluorouracil, and prednisone (CMFP) for the treatment of metastatic breast cancer. There were 427 patients entered into the study and randomly assigned to one of the two treatments, i.e. the five drug therapy CMFPV or the four drug therapy CMFP. The differences in patient survival and tumor response between the two treatment groups were not statistically significant. The data were also analyzed using multivariate procedures to determine those factors ascertained at entry into the study which were predictors of survival or predictors of response to therapy. The one factor that predicted both response and survival was performance status. An additional important predictor of survival was sites of metastatic involvement. Other significant predictors of response were menopausal age, BUN, and hematocrit.