Pregnancy-associated breast cancer: a case— control study in a young population with a high-fertility rate

Abstract

Pregnancy-associated breast cancer (PABC) is not a rare event. The association frequently imposes a management challenge. We intended to review the clinical features, therapy, and outcome of patients with PABC seen at a single institution over a five-year period and to compare those with that seen in a matched control group.

Data of all patients with PABC diagnosed during pregnancy were retrospectively reviewed (Group I). For each patient in Group I, three matched controls with breast cancer without pregnancy were identified (matched for age, stage, and year of diagnosis, Group II).

72 patients in Group I and 216 in Group II were identified. Their median age was similar (34 vs 35 y, respectively). The median number of prior pragnancies for patients in Groups I and II was 5. Patients had shorter duration of symptoms prior to diagnosis as compared with their controls (5.6 vs 9.4 months,P<0.0001). 3%, 31%, 40%, and 26% of patients had Stage I to IV, respectively. A pattern that was similar to that seen in our breast cancer population. Pregnancy was terminated in 34 patients (47%), while 38 (53%) had normal spontaneous vaginal delivery. 47 patients in Group I had surgery; 37 (52%) had modified radical mastectomy and 10 (14%) had conservative surgery. In 37 patients surgery was performed after termination of pregnancy and 10 had surgery performed during pregnancy. The median number of positive lymph nodes in Group I was 4 as compared with 2 for patients in Group II. No patients in Group I had systemic chemotherapy during first trimester, while only 4 (6%) and 3 (4%) received adjuvant or neoadjuvant during second and third trimester, respectively. No congenital malformation in the newborns was diagnosed. None of the patients in Group I received radiotherapy during pregnancy.