Aims: To assess the effect of prognostic factors on overall survival from node negative breast cancer.
Methods: Information was collected on 1138 node negative breast cancer patients in the Auckland region, diagnosed between 1976 and 1985. Prognostic variables investigated included oestrogen (ER) and progesterone (PR) receptor status, tumour grade, tumour size, body mass index, lactation history and parity. The effects of these variables on overall survival were assessed separately in pre and postmenopausal groups.
Results: Over a median follow up time of 10.2 years, improved survival was seen in premenopausal women with PR+ status (p = 0.0007), ER+ status (p = 0.03), positive lactational history (p = 0.03) and low tumour grade (p = 0.04). In postmenopausal women, only ER+ status (p = 0.01) and PR+ status (p = 0.02) were associated with improved survival. Multivariate analysis suggested that positive PR status combined with tumour size provided the best prognostic discrimination in premenopausal women, whereas ER status was the dominant prognostic variable in postmenopausal patients.
Conclusions: For premenopausal node negative women, progesterone receptor status, considered either alone, or together with tumour size, provides the best prognostic prediction of survival. By comparison, oestrogen receptor status is the most important predictor of overall survival in postmenopausal women.