Natural history of more than 20 years of node-positive primary breast carcinoma treated with cyclophosphamide, methotrexate, and fluorouracil-based adjuvant chemotherapy: a study by the Cancer and Leukemia Group B.

Purpose: Breast cancer heterogeneity dictates lengthy follow-up to assess outcomes. Efficacy differences for three regimens that are based on adjuvant cyclophosphamide, methotrexate, and fluorouracil (CMF) are presented in this article, but cancer recurrence sites, time of relapse, subsequent primary cancers, and causes of death in the natural history of node-positive breast cancer are emphasized.

Patients And Methods: Beginning in 1975, 905 patients with node-positive cancer were randomly assigned to receive CMF or two regimens of CMF plus other agents.