Successful expectant management of a giant chorioangioma

Abstract

Giant chorioangiomas are benign placental tumours, which can have potential severe fetal consequences. Complications in pregnancy include polyhydramnios, fetal hydrops and growth restriction. Such pregnancies can carry a significant risk of poor perinatal outcome and require close monitoring. Therapeutic options include fetoscopic or interstitial vessel ablation, chemosclerosis and embolisation. Where there is no evidence of fetal compromise, such pregnancies can successfully be managed conservatively.

Background

Giant chorioangiomas are rare benign tumours of the placenta.¹ Small lesions are a relatively common incidental finding in pregnancy. However, large tumours exceeding 40–50 mm carry an increased risk of fetal complication during pregnancy.

Case presentation

A 33-year-old woman of Chinese origin (gravida 2, para 1) presented for routine care during her second (singleton) pregnancy. She had one previous pregnancy, which was complicated by gestational diabetes, with ventouse delivery at 37-week gestation. During this second pregnancy, she again developed gestational diabetes and later required insulin therapy from 30-week gestation. At her routine anomaly scan at 20 weeks, the ultrasound revealed a single structurally normal fetus with a 44×50×26 mm hypoechoic placental mass on the fetal side (figure 1). The mass demonstrated internal vascularity, consistent with a chorioangioma. The woman was subsequently referred to the regional fetal medicine unit for ongoing ultrasound surveillance.

Figure 1.

Ultrasound image at 20-week gestation demonstrating a hypoechoic placental mass on the fetal side of the placenta, consistent with a chorioangioma.

Investigations

The woman underwent fortnightly ultrasound surveillance for fetal biometry, middle cerebral and umbilical artery Doppler studies and amniotic fluid volume. Umbilical artery and middle cerebral artery (MCA) Doppler studies (pulsatility index, resistance index and end-diastolic flow) remained normal throughout the pregnancy. At 29-week gestation, ultrasound demonstrated that the mass increased in size to 70×55×64 mm (figures 2 and 3).

Figure 2.

Ultrasound image at 28-week gestation demonstrating increased growth.

Figure 3.

Ultrasound at 28-week gestation demonstrating a feeding vessel into the chorioangioma, on colour flow Doppler.

Treatment

The woman was managed expectantly with fortnightly ultrasound scans at the tertiary fetal medicine unit. The chorioangioma remained stable in size at 76 mm. Throughout the pregnancy, there was no evidence of fetal hydrops, anaemia or polyhydramnios. MCA and umbilical artery Doppler studies, which remained normal throughout the pregnancy and the fetus maintained normal growth velocity. In view of these findings, administration of corticosteroids were not indicated as there was no requirement of early delivery. The patient did not require antenatal admission to hospital at any point. At 35-week gestation, the woman was subsequently discharged back to her local obstetric unit for ongoing fetal surveillance. In view of the patient’s gestational diabetes, which required insulin treatment, her local obstetric team planned for an induction of labour at 38-week gestation.

Outcome and follow-up

The woman experienced an antepartum haemorrhage at 37+4 weeks followed by spontaneous onset of labour. The fetus was monitored continuously throughout the labour. Labour was uncomplicated, with no further episodes of antepartum haemorrhage. The patient had a normal vaginal delivery of a live female infant, weighing 2650 g. Macroscopic assessment of the placenta revealed an 80-mm solid tumour. Histopathological examination confirmed a chorioangioma (figures 4 and 5).

Figure 4.

The placenta following delivery, demonstrating the chorioangioma on the fetal side of the placenta.

Figure 5.

Macroscopic examination of the chorioangioma.

Discussion

Chorioangiomas are the most common benign tumour of the placenta. It is an angioma which arises from chorionic tissue.² Such lesions have no malignant potential. Associations include a female fetus, diabetes mellitus and multiple pregnancies.^1–3 The incidence of small tumours is 1% of all pregnancies and, therefore, most lesions represent a benign incidental finding. Large or ‘giant’ chorioangiomas are lesions which arbitrarily exceed 40–50 mm. Lesions of this size are rare and affect approximately 1:9000–1:50 000 pregnancies.¹ They are associated with risk of antenatal complications, adverse perinatal outcome and a perinatal mortality of up to 40%.^{1 4} Adverse fetal outcome appeared to be related to the tumour size.⁵

Complications during pregnancy arise from the potential for the formation of an arteriovenous shunt. As a result of the ensuing hyperdynamic circulation with increased venous return to the heart, the fetus can develop congestive heart failure, non-immune hydrops and growth restriction.^{2 3} In turn, this can cause placental abruption, pre-eclampsia and preterm labour.³ Fetal thrombocytopaenia can develop from sequestration of platelets by the tumour.³ Polyhydramnios is a frequently reported complication.^{1 4–6} This is proposed to be either a consequence of increased urine production secondary to a hyperdynamic circulation or from excessive fluid may transudate through the vascular tumour surface.^{1 3 7} Polyhydramnios can complicate the pregnancy by increasing the risk of preterm delivery, preterm rupture of membranes and placental abruption. The presence of non-immune fetal hydrops further increases the risk of adverse complications and is strongly associated with an increased risk of fetal morbidity and mortality.^{4 5} Fetal growth restriction has also been described, through the mechanism of fetal blood being shunted away from the intervillous circulation.⁸

In patients who do not undergo in utero treatment, the complication rate still remains significant. Buca et al performed a systematic review of 106 singleton pregnancies, which did not undergo in utero intervention.⁵ In this meta-analysis, 8.2% of pregnancies ended in intrauterine death. Neonatal and postnatal deaths were reported as 3.8% and 11.1%, respectively. Small for gestational age fetus at birth was found in 24%. Spontaneous preterm birth affected 18.6% of pregnancies. Hydrops was identified antenatally in 14% and polyhydramnios was reported in 37.8%. Maternal complications were present in 20.5%, which predominantly comprised pre-eclampsia. Pregnancies which do not undergo in utero treatment are, therefore, still at high risk of complications.

Diagnosis

Giant chorioangiomas are usually detected on ultrasound identification of a well-circumscribed hypoechoic mass located in the chorionic plate. Feeding vessels into the lesion may be demonstrated on colour flow Doppler. Fetal ultrasound may show signs of fetal anaemia, heralded by increased peak systolic velocity in the fetal MCA.⁵ In this described case, MCA and umbilical artery Doppler assessment remained normal throughout.

Management

Small chorioangiomas which are less than 40 mm are common incidental findings and require no further monitoring or management. Larger tumours exceeding 40 mm are associated with a greater risk of maternal–fetal complications and require close regular surveillance for fetal compromise.^1–3 Approximately 50% of large chorioangiomas develop maternal or fetal complications requiring intervention or delivery.⁴ The management of giant chorioangioma is dependent on the presence of complications and should be individualised. However, the majority of patients can be managed expectantly.⁸

The optimal management of giant placental chorioangioma remains undetermined.⁶ Therapeutic options are numerous and primarily aim to devascularise the tumour, thereby arresting shunt physiology.^{6 9} The determinants of the treatment modality include the site of the chorioangioma, accessibility, size and number of feeder vessels, tumour proximity to the cord insertion and expertise of the operator.^{4 9} Intervention has been proposed to only be necessary when there are ultrasound features of fetal compromise.⁴ Described techniques include fetoscopic or interstitial laser ablation of the tumour feeding vessel, embolisation, chemosclerosis with alcohol, medical treatment with propanolol and vessel ligation.^{2 10 11} Fetoscopic laser photocoagulation has been reported to be successful in 60%–80% but can be challenging in the presence of an anterior placenta.^{4 10} An interstitial approach may be preferable in these circumstances.¹⁰ Chemosclerosis with absolute alcohol has been reported as a successful treatment modality. However, this method carries the risk of potential fetal exposure, non-target embolisation and fetal death.7 9 10 12 Medical management with propranolol has also been described.¹¹ This regime is a pharmacological alternative to an invasive procedure and is proposed to limit the increase in chorioangioma volume. Therapy with intravascular embolisation using enbucrilate, tissue glue or by microcoiling have also been used successfully.4 6 9 13 This has the advantage of being minimally invasive, offering more targeted vessel occlusion and the avoidance of collateral injury from thermal energy. However, complications such as portal vein thrombosis have been described where liquid embolic agents are used.^{6 13} Embolism by microcoiling initiates clot formation at the vessel insertion site and have the advantage of being unable to migrate through the tumour vascular bed. This minimises the risk of downstream embolisation.⁶

In addition to devascularising treatments, supportive measures may also be employed. Amnioreduction has been described for the treatment of severe symptomatic polyhydramnios.^{3 4} The presence of fetal anaemia from a hyperdynamic circulation may require fetal transfusion.1 3 4 8 14 Delivery should be considered where there are complications emerging after 34 weeks of gestation.^{2 3}

The optimum management for giant chorioangioma has not yet been established. Currently, there are a lack of randomised trials and a paucity of published clinical cases to inform about which patients with large chorioangioma should undergo in utero treatment, the benefit of treatment over conservative management or of the optimum treatment regime which should be employed,.^{4 5 15}

In this described case, no fetal compromise was identified. Close fetal surveillance with expectant management resulted in a successful pregnancy outcome.

Conclusion

Large placental chorioangiomas are rare lesions, which can potentially cause adverse fetal complications. In view of the associated significant perinatal mortality rate, it is necessary for accurate detection and appropriate management, with regular follow-up and timely decision for delivery. Obstetricians should be aware of the possibility of chorioangioma as complications and fetal losses may be avoidable.

This case illustrates a woman with a large placental chorioangioma, which did not develop any complications and which was successfully managed expectantly. Although this is not a new observation and has been previously reported, it highlights that a randomised controlled study to inform on the optimum management of large chorioangioma is still missing.

Patient’s perspective.

Having undergone a relatively uncomplicated first pregnancy, I was surprised and dismayed at the findings at the chorioangioma at the 20-week anomaly scan. I underwent routine fetal surveillance both locally and at the regional fetal medicine unit. The care I received from both the fetal medicine unit and my local unit was comprehensive and extremely efficient. The staff who looked after me throughout the pregnancy were exemplary. I was fortunate to not require any further intervention for the chorioangioma and had an exceptionally straightforward delivery of a healthy daughter.

Learning points.

• Giant chorioangiomas exceeding 40 mm are rare benign placental tumours, which require regular fetal medicine ultrasound surveillance.

• The pregnancy should be monitored for polyhydramnios, fetal growth restriction and signs of fetal anaemia.

• Where complications are identified, therapeutic options aim to ablate the vessels which feed into the lesion.

• In the absence of complicating factors, expectant management of giant chorioangioma can have a good outcome.

• A large study to inform on the optimum management of large chorioangioma still needs to be conducted.