Breast cancer and pregnancy: a comparative analysis of a Chilean cohort

INTRODUCTION: Recent reports show that pregnancy-associated breast cancer (PABC) survival is similar to that of non-pregnant young patients. We evaluate the characteristics and prognosis of PABC patients treated in our cancer centre. PATIENTS AND METHODS: We identified patients with invasive PABC who were treated between 1999 and May 2013 and compared their characteristics with a no PABC cohort of similar age. RESULTS: The prevalence of PABC was 1% (n = 17). The median age was 35 years (range: 29– 42 years). The initial tumour was suspected clinically in 93% of the cases. Total mastectomy rates were higher in women with PABC (78.6% versus 40.5%, p = 0.02), and more tumours in the PABC group were triple negative, epidermal growth factor type 2 (HER2)–positive, and at advanced stages; however, these differences were not statistically significant. While estimated overall survival at ten years was higher in the non-PABC group (75.5% versus 80.5%, p = 0.043), disease-specific survival (DSS) rate at ten years was not statistically different between groups (83.9% for PABC and 75.5% for unrelated pregnancy BC, p = 0.37). CONCLUSIONS: PABC is a rare event. In our cohort, it tended to be more aggressive. Compared with a similar age cohort, the DSS was not worse.