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

Pregnancy-associated breast cancer (PABC) is not a rare event. The associat ion frequently imposes a management challenge. We intended to review the cl inical features, therapy, and outcome of patients with PABC seen at a singl e institution over a five-year period and to compare those with that seen i n a matched control group. Data of all patients with PABC diagnosed during pregnancy were retrospectiv ely reviewed (Group I). For each patient in Group I, three matched controls with breast cancer without pregnancy were identified (matched for age, sta ge, and year of diagnosis, Group II). 72 patients in Group I and 216 in Group II were identified. Their median ag e was similar (34 vs 35 y, respectively). The median number of prior pregna ncies 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, r espectively. A pattern that was similar to that seen in our breast cancer p opulation. Pregnancy was terminated in 34 patients (47%), while 38 (53%) ha d normal spontaneous vaginal delivery. 47 patients in Group I had surgery; 37 (52%) had modified radical mastectomy and 10 (14%) had conservative surg ery. In 37 patients surgery was performed after termination of pregnancy an d 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. N o patients in Group I had systemic chemotherapy during first trimester, whi le only 4 (6%) and 3 (4%) received adjuvant or neoadjuvant during second an d third trimester, respectively. No congenital malformation in the newborns was diagnosed. None of the patients in Group I received radiotherapy durin g pregnancy. Over a median of 47.5 months, 48 (67%) patients in Group I wer e alive as compared to 126 (58%) in Group II, with no difference in the med ian survival (P = 0.79). Comparing overall survival (OS) between the two gr oups stage for stage also showed no significant difference. Also there was no difference in progression-free survival between the two groups. Cox prop ortional hazard model identified advanced stage as the only independent adv erse prognostic variable that influenced OS in Group I. Despite that this s eries included a relatively young population with a high fertility rate, th e study confirmed the lack of a survival difference between patients with P ABC and their matched controls.