Pregnancy-associated breast cancer

Breast masses discovered during pregnancy should receive thorough evaluation. Delay in the diagnosis of breast cancer in pregnancy may cause increased mortality and should be avoided. As women delay childbearing, the incidence of breast cancer during pregnancy may increase. This article aims to review the pathophysiology, clinical presentation, and diagnostic and therapeutic approach to the pregnant breast cancer patient. In addition, the impact of pregnancy on subsequent breast cancer development in high-risk groups, such as BRCA1 and BRCA2 mutation carriers and patients with a prior history of breast cancer, is discussed. SOURCES AND STUDY SELECTION: We conducted a PubMed search using the words breast, cancer, carcinoma, and pregnancy. We also searched for abstracts presented at the American Society for Clinical Oncology meetings using the words breast cancer and pregnancy. Observational studies were not pooled because of the disparity of the data. We reviewed 117 articles and three abstracts referring to breast cancer in pregnancy.

A thorough breast examination at the first antenatal visit, before the physiologic changes in breast parenchyma obscure a possible mass, is essential. The work-up of masses detected during pregnancy should not be postponed until after delivery. Delays in diagnosis may contribute to the higher proportion of patients with advanced stage at presentation. The prognosis of the pregnant breast cancer patient is similar to her stage-matched nonpregnant counterparts in most series. Radiation therapy is contraindicated during pregnancy; this limits breast conservation to cases presenting during the third trimester. Some chemotherapies can be administered during the second and third trimesters. Therapeutic abortion is not necessary, although women with high-risk disease may find this preferable. Women with a history of breast cancer should be reassured that subsequent pregnancy is not known to increase the risk of recurrence. Women with a history of BRCA1/2 mutations should not be advised that early pregnancy decreases their breast cancer risk.

Physicians should aggressively pursue work-up in women with a palpable breast mass because early diagnosis may improve the prognosis of breast cancer during pregnancy.