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

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.

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.

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).

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.