Behavior and outcomes of pregnancy associated breast cancer: a cohort study

Introduction: Pregnancy Associated Breast cancer (PABC) is associated with poor prognosis and a decreased overall survival. A retrospective review was conducted to review the experience and outcome in a tertiary care hospital, and to compare those seen in a matched group for year of diagnosis. Materials and Methods: This is a retrospective review of a prospectively collected breast cancer registry. The study was conducted in a tertiary care hospital in Riyadh, Saudi Arabia from January to Decamber 2014 . Female patients with PABC were identified and matched with similar cohort of non-pregnant breast cancer patients that were diagnosed between 2001-2010. Clinical data including age, tumor biology, clinical stage, follow up and outcomes (disease free survival, DFS) were analyzed and compared between the two groups using SAS 9.3 and R-2.14.1 Results: A total of 110 patients in Group 1 and 114 patients in Group II were analyzed. In both groups, the patient age ranged was between 20 to 45 years; the median follow up was 34 months in PABC and 54 months in non-pregnant cohort. PABC were statistically more likely to be triple negative (p value-0.05) and diagnosed at advanced stage (stage 3 and 4) (p value-0.02). There was no difference in the occurrence of Her-2 positive disease. In pregnant patients there was a 5-year survival rate of 65% compared to non-pregnant cohort of 82% with p value of 0.002 and DFS was also 47.5% versus 65.4% with a p value .002 which is statistically significant. Conclusion: Pregnancy associated breast cancer (PABC) is diagnosed at a more advanced stage and tends to be triple negative and they are associated with a worse DFS and overall survival. Early detection during pregnancy may improve outcome.