Evolution of Angiogenic Factors in Pregnant Patients with Breast Cancer Treated with Chemotherapy.

High prevalence of placental-derived complications, such as preeclampsia and intrauterine growth restriction, has been reported in women with breast cancer (BC) treated with chemotherapy during pregnancy (PBC-CHT). Aim: To ascertain whether PBC-CHT is associated with an imbalance of angiogenic factors, surrogate markers for placental insufficiency, that could explain perinatal outcomes. Methods: Prospective study between 2012 and 2016 in a single institution. Soluble fms-like tyrosine kinase (sFlt-1), placental growth factor (PlGF), and soluble endoglin (sEng) in maternal blood were assessed throughout pregnancy in 12 women with BC and 215 controls. Results: Cancer patients were treated with doxorubicin-based regimes and with taxanes. Ten PBC-CHT (83%) developed obstetrical complications. At the end of the third trimester, significantly higher levels of sFlt-1; sFlt-1/PGF ratio, and sEng levels were observed in BC women as compared to controls. Moreover; there was a significant correlation between plasma levels of sFlt-1 and the number of chemotherapy cycles administered. Besides, more chemotherapy cycles correlated with lower birthweight and head circumference at birth. Conclusions: Women with BC treated during pregnancy showed an antiangiogenic state compatible with placental insufficiency. Angiogenic factors could be useful in the clinical obstetric management of these patients; although further studies will be required to guide clinical decision-making.