Prognostic role of pregnancy occurring before or after treatment of early breast cancer patients aged35 years: a GET(N)A Working Group analysis

BACKGROUND: Usual practices recommend waiting at least 2 years between diagnosis of early breast cancer (EBC) and pregnancy. Few data highlighted a harmful effect of an early pregnancy for low-risk patients. The authors analyzed retrospectively data from women younger than 35 years who became pregnant before or after treatment of EBC. METHODS: Between 1990 and 1999, 908 consecutive EBC patients were analyzed. The primary endpoint was to compare overall survival (OS) between pregnant and nonpregnant patients. The secondary endpoint was to establish a score index laying down the risk of distant recurrence. RESULTS: Within the year before the diagnosis, 105 (11.6%) patients became pregnant and 118 (13%) were pregnant after treatment. In a multivariate model, a pregnancy before the diagnosis was not predictive of death but of local relapse. A pregnancy subsequent to breast cancer therapy resulted in a 77% decrease of death (P < .001). In good-prognosis score index patients, the annual risk of relapse remained low. In patients having the higher score, recurrences occurred mainly during the first years after the treatment. Beyond 80 months, the annual risk of relapse seemed to be similar to those of lower-risk subgroups. CONCLUSIONS: In women aged younger than 35 years, a pregnancy occurring before or after the diagnosis of breast cancer was not an independent prognostic factor of death. In the subset of patients having a high risk of relapse, it may be preferable to postpone a pregnancy beyond 5 years after the breast cancer therapy.