Spine | Large sacrococcygeal teratomas / placental chorioangiomas
Fetal vascular tumours such as sacrococcygeal teratomas (SCT) or placental chorioangiomas are growths that are usually benign (not-cancerous) masses of tissue and blood vessels. Very large tumours may “steal” blood from the fetal circulation, resulting in the fetal heart having to work much harder to pump blood to the circulation. In these cases, heart failure may develop.
- The most common fetal tumour is a sacrococcygeal teratomas (SCT), which develops before birth and grows from the coccyx (or tailbone) of a developing fetus.
- A placental chorioangioma is a benign tumour that is located within the placental tissue.
- Both SCTs and placental chorioangiomas are made up of many blood vessels, and, when they grow to be very large, may “steal” blood from the fetal blood circulation.
- In cases of large tumours, the fetal heart may have to pump harder to allow blood to reach the fetal circulation, and heart failure may develop.
- Heart failure in the fetus may present as a condition called “hydrops” which is an accumulation of fluid under the fetal skin or in the fetal abdomen or chest. Fetuses with this condition are very sick and may not survive.
A sacrococcygeal teratoma (SCT) is a rare tumour, typically located at the fetal tailbone (or coccyx). Although SCTs are usually not cancerous, they are made up of many blood vessels and can grow to become very large. Females are four times more likely to be born with this condition than males.
A placental chorioangioma is a rare, benign tumour of the placenta. Similarly to SCTs, these may grow to become very large.
SCTs and placental chorangiomas are usually diagnosed on ultrasound, although the size and appearance of the masses varies significantly.
Large tumours may “steal” or divert blood flow away from the fetus so as to facilitate their growth. In these cases, the fetal heart may compensate by pumping harder. Eventually, however, the heart will not be able to maintain this high output and heart failure may develop. This may be seen by studying the heart’s appearance on a focused ultrasound (called a “fetal echocardiogram”) but may also become evident by the accumulation of fluid under the fetal skin or in the fetal abdomen or chest (a condition called “hydrops”). Fetuses with hydrops are very sick and may not survive.
Fetal vascular tumours such as SCTs or placental chorioangiomas must be monitored closely with ultrasound so as to ensure adequate fetal growth and wellbeing. Mothers must also be monitored closely because, rarely, the tumours may cause the mother to develop a severe condition called mirror syndrome. In this case, mothers may develop high blood pressure, and fluid may accumulate, similar to the fetus, in their lungs or in their lower limbs.
In most cases, fetal vascular tumours will be monitored with ultrasound only and no intervention will be necessary. In severe cases, fetal surgery may be necessary to interrupt the blood flow to the tumour and allow it to shrink.
Referral Information (for physicians)
Large solid sacrococcygeal teratomas or placental chorioangiomas resulting in cardiac failure and hydrops prior to 30 weeks’ gestation.
Refer if signs of hydrops or high output cardiac failure present. The timing and type of procedure will be individualized based on patient presentation. Radio-frequency ablation procedures typically require 24 hours of hospitalization. In the presence of hydrops, monitoring for mirror-syndrome is required. Postoperatively, out-of-province patients will be referred back to their local provider for further antenatal care and delivery. Local patients will be followed and delivered at Mount Sinai Hospital.