REPRODUCTIVE HISTORY AND PROGNOSIS IN PATIENTS WITH OPERABLE BREAST-CANCER

Background. Late menarche, early menopause, high parity, and early fir st birth decrease the risk of development of breast cancer. The influe nce of these factors on the survival of breast cancer patients has not been explained. Methods. A group of 1885 patients with operable breas t cancer was studied retrospectively. A univariate analysis was used t o calculate 10-year overall survival (OS) and disease free survival (D FS) in relation to age, menopausal status, age at menarche and menopau se, and number of pregnancies and deliveries. A multivariate analysis (Cox model) was performed in which classic prognostic factors (tumor s ize and grade, lymph node involvement) were included in addition to re productive factors. Results. Univariate analysis demonstrated better p rognosis in patients who had never been pregnant compared with those w ho had (OS, 62% vs. 54%, respectively; P = 0.01; DFS, 53% vs. 44%, res pectively; P = 0.005) and in nulliparous compared with parous patients (OS, 62% vs. 53%, respectively; P = 0.006; DFS, 52% vs. 44%, respecti vely; P = 0.004). Survival rates decreased with the number of pregnanc ies and deliveries. Patients with late menarche had worse survival the n those whose first menstruation occurred before the age of 16 years ( DFS, 47% vs. 41%, respectively; P = 0.04). By multivariate analysis, p arity remained an independent prognostic indicator in addition to clas sic highly significant prognostic factors (nodal involvement, tumor gr ade and size). Conclusions. Results suggest that reproductive factors known to decrease the risk of breast cancer development have an advers e effect on prognosis.