The influence of timing of surgery in relation to menstrual period on survival of breast cancer patients has been both advanced advocated and disputed. A meta-analysis on published series showed a statistically significant overall odds reduction when surgery is performed in the luteal phase. The records of 165 premenopausal M- breast cancer women, not on hormonal therapies, consecutively operated on from 1977 to 1991 were reviewed. All patients underwent modified radical mastectomies or quadrantectomies plus operative radiotherapy, Node-positive patients received standard adjuvant chemotherapy. Cox regression analysis was used to estimate the relative risk (RR) of death in three models including timing of surgery, age, histology, pathological T and N. In each model, patients were divided into two groups according to the criteria proposed by Badwe, Hrushesky, and Senie. Multivariate analysis showed a significant association between pT and pN and survival, whereas no association with survival was observed for timing of surgery according to Badwe or Hrushesky or Senie criteria (RR = 1.26, RR = 0.91, and RR = 0.88 respectively). Up-to-date agreement on the menstrual phase and relative expected better prognosis is still lacking.