Age at menarche as a prognostic factor in human breast cancer.

Abstract An analysis of a series of 926 female patients, of whom 755 were followed for 3 years and 647 for 5 years after mastectomy, revealed age at menarche to be a valuable prognosticator. Survival rates were the lowest for women who had very early menarche (≦ 11 years of age) but prognosis improved progressively with increase in menarchial age. Optimal menarchial age was found to be at age 15 ; onset of menses beyond this age was once again associated with an unfavorable outcome. The possible relationship between age at menarche and axillary node involvement was then examined from two points of view in an effort to establish whether early menarche would be associated with extensive nodal involvement, or whether it would retain its unfavorable prognostic significance independently of the extent of this involvement. Both of these hypotheses were found to be plausible in our series. It is stressed that further research on larger study populations is required before definitive conclusions can be drawn.