[Pregnancy-Associated Breast Cancer: An analytical observational study].

BACKGROUND AND OBJECTIVE: Pregnancy-associated breast cancer is defined as breast cancer diagnosed during pregnancy and up to one year postpartum.

PATIENTS AND METHOD: A retrospective, analytical, observational study comparing 56 cases of breast cancer and pregnancy (PABC) diagnosed 1976-2008 with 73 patients with breast cancer not associated with pregnancy (non-PABC) was performed. Demographic data, prognostic factors, treatment and survival were reviewed and compared.

RESULTS: The prevalence of PABC in our center is 8.3/10,000. The highest frequency (62%) appeared during the postpartum period. The stages are higher in PABC, being 31.3% advanced (EIII and EIV) in PABC versus 13.3% in non-PABC (P < .05). Regarding prognostic factors, 27.3% in PABC had a tumoral grade 3 versus 15.8% of non-PABC. Among women with PABC, 33.3% had negative estrogen receptors, 48.7% negative progesterone receptors and 34.5% positive Her2Neu compared with 22.2, 24.1 and 31%, respectively of non-PABC patients. Finally, positive lymph nodes were found in 52.8% of PABC, versus 33.8% non-PABC (P < .05). Overall and disease-free survival rate at 5 years for PABC was 63.7 and 74.2%, respectively.

CONCLUSIONS: The poorer survival observed is possibly due to the presence of adverse prognostic features such as lymph node metastases, negative hormone receptors, tumoral grade iii, as well as a delay in diagnosis with a higher rate of advanced stages.