Pregnancy-associated breast cancer: Management of the mother, fetus and tumour

Introduction: Pregnancy-associated breast cancer (PABC) is described as breast cancer diagnosed within pregnancy or within 1 year postpartum. PABC is becoming more common due to delayed childbearing, with older maternal age increasing the likelihood of tumorigenesis coinciding with pregnancy. Our review aims to outline the important principles of managing PABC, and discusses future fertility implications, genetic testing and postnatal considerations that are not often considered in other existing reviews. Method: A literature search was conducted using PubMed, Cochrane and Google Scholar databases. Results: A persistent breast mass in pregnant women should be evaluated with a breast ultrasound. Total mastectomy is the standard treatment in the first trimester. Chemotherapy is contraindicated in the first trimesters, but can be given in the second and third trimester, and stopped before 35 weeks. Radiotherapy should be delayed until delivery, and hormone receptor therapy is contraindicated in pregnancy. A multidisciplinary team involving an obstetrician, medical oncologist and other allied health professionals is crucial. Delivery should be planned as close to 37 weeks as possible, and at least 3 weeks after the last chemotherapy cycle. Vaginal delivery is preferred, and breastfeeding can resume 14 days after the last chemotherapy regime. Conclusion: A breast mass in a pregnant woman should not be dismissed. PABC must be managed by multidisciplinary teams at tertiary medical centres with access to surgery and chemoradiation therapies. Management strategies must include safe management and delivery of the fetus, contraception and future fertility planning.