Radiofrequency thermal ablation of giant placental chorioangioma complicated with fetal hydrops: a case report and successful outcome

Chorioangiomas are the most frequently occurring type of benign tumour of the placenta. However, large chorioangiomas greater than 4 cm are rare and can be more frequently associated with serious complications such as: polyhydramnios, hydrops fetalis, fetal anaemia, intrauterine growth restriction, preterm birth, and an increased risk of perinatal mortality. Importantly timely prenatal diagnosis with close surveillance alongside potential intrauterine intervention can prove impactful on pregnancy outcome and fetal survival. We present a case of a 36-year-old female referred to our tertiary fetal medicine unit at 28 weeks’ gestation with a large chorioangioma measuring 9.4×8.8×5.5 cm and ultrasonographic evidence of severe fetal anaemia and fetal hydrops. The patient underwent an intrauterine transfusion and in utero surgical therapy with radiofrequency ablation (RFA). Immediately following the procedure, the fetus sustained a period of bradycardia, followed by asystole. Delivery was expedited via emergency caesarean section. Careful planning and rapid delivery after fetal intervention within the most appropriate surgical setting mitigated risks for the baby and resulted in a positive outcome. The baby was discharged from the neonatal unit on day 84 of life. Large placental chorioangiomas are a rare occurrence, however, when associated with fetal complications present a high incidence of adverse perinatal outcomes. In utero interventions require careful planning and surgical expertise to ensure improved fetal and neonatal outcomes. To the best of our knowledge this case is the first recorded instance of a successful postnatal outcome following RFA for a large placental chorioangioma, whereby the fetus was complicated by fetal hydrops.