Pregnancy-associated breast cancer (PABC): a matched case-control study of young women

To compare the clinical characteristics and prognosis of pregnancy-associated breast cancer (PABC) patients and non-PABC subjects in Hebei Breast Disease Treatment Center. A total of 40 PABC patients, including 10 pregnant women and 30 postpartum women, and 80 non-PABC subjects were recruited. The mean age of pregnancy in PABC patients was significantly older than that of non-PABC subjects (26.8 years vs. 23.5 years, P<0.05). Categorized by the receptor status, the ratio of hormone receptor (HR) positive breast cancer was lower in PABC patients than that of non-PABC subjects (57.5% vs. 70.0%, P=0.221), while the ratios of HER2- (42.5% vs. 37.5%, P=0.692) and triple-negative PABC patients (20% vs. 12.5%, P=0.578) were higher than those of non-PABC patients, although no significant differences were detected. There were no significant differences in the DFS (54.2 months vs. 63.5 months, P=0.271) and OS (54.2 months vs. 65.4 months, P=0.116) between PABC patients and non-PABC subjects. Compared with non-PABC subjects, the average age of pregnancy of PABC patients was later, while share similar pathological characteristics, as well as DFS and OS.