Taxanes for the treatment of breast cancer during pregnancy: an international cohort study

Introduction: The addition of taxanes to anthracycline-based chemotherapy is considered standard of care in the treatment of breast cancer. However, there are insufficient data regarding the safety of taxanes during pregnancy. The aim of this study was to describe the incidence of obstetric and neonatal adverse events associated with the use of taxane-containing chemotherapy regimens for the treatment of breast cancer during pregnancy. Methods: This is a multicenter, international cohort study of breast cancer patients treated with taxanes during pregnancy. A descriptive analysis was undertaken to synthetize available data. Results: A total of 103 patients were included, most of whom were treated with paclitaxel and anthracyclines given in sequence during gestation (90.1%). The median gestational age at taxane initiation was 28 weeks (range ¼ 12-37 weeks). Grade 3-4 adverse events were reported in 7 of 103 (6.8%) patients. The most common reported obstetric complications were intrauterine growth restriction (n ¼ 8 of 94, 8.5%) and preterm premature rupture of membranes (n ¼ 5 of 94, 5.3%). The live birth rate was 92 of 94 (97.9%), and the median gestational age at delivery was 37 weeks (range ¼ 32-40 weeks). Admission to an intensive care unit was reported in 14 of 88 (15.9%) neonates, and 17 of 70 (24.3%) live births resulted in small for gestational age neonates. Congenital malformations were reported in 2 of 93 (2.2%). Conclusion: Obstetric and neonatal outcomes after taxane exposure during pregnancy were generally favorable and did not seem to differ from those reported in the literature with standard anthracycline-based regimens. This study supports the use of taxanes during gestation when clinically indicated.