Prognosis of pregnancy-associated breast cancer: a meta-analysis of 30 studies.
BACKGROUND
Pregnancy-associated breast cancer (PABC) is relatively rare with considerable controversy regarding its prognosis.


METHODS
Two of the authors independently performed a literature search with no date or language restrictions. Eligible studies were control-matched, population-based and hospital-based studies that addressed the outcome of patients diagnosed during pregnancy or 1-year afterwards. The primary and secondary end-points were overall and disease-free survival respectively. Pooling of data was done using the random effect model.


RESULTS
30 studies were included in this meta-analysis (3,628 cases and 37,100 controls). PABC patients had a significantly higher risk of death compared to those with non-pregnancy-related breast cancer (pooled hazard ratio (pHR): 1.44; 95% CI [1.27-1.63]). The same results were encountered on restricting the analysis to HRs of multivariate analyses (pHR: 1.40 [1.17-1.67]). A clearer trend of poorer outcome was seen in those diagnosed postpartum (pHR: 1.84; 95% CI [1.28-2.65]) than those diagnosed during pregnancy (pHR: 1.29; 95% CI [0.74-2.24]). DFS analysis showed a significantly higher risk of relapse associated with PABC as well (pHR: 1.60 [1.19-2.16]).


CONCLUSIONS
Our results show that PABC is independently associated with poor survival particularly those diagnosed shortly post-partum. This underscores a possible impact of the pregnant breast microenvironment on the biology and consequently the prognosis of these tumors.
Breast Cancer Translational Research Laboratory J.C. Heuson, Université Libre de Bruxelles, Institut Jules Bordet, 1000 Brussels, Belgium. hatem.azim@bordet.be
Hatem A
HA
Azim
Luigi
L
Santoro
William
W
Russell-Edu
George
G
Pentheroudakis
Nicholas
N
Pavlidis
Fedro A
FA
Peccatori
D001943:Breast Neoplasms / Q000401:mortality*; D016022:Case-Control Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D011247:Pregnancy; D011252:Pregnancy Complications, Neoplastic / Q000401:mortality*; D011379:Prognosis; D015996:Survival Rate