diagram of Sacrococcygeal
What is a sacrococcygeal teratoma (SCT)?
SCT is a tumor located at the superior portion of the buttocks which is comprised of different types of embryological tissue. The tumor usually has solid and cystic components and may be highly vascular. If diagnosed in the neonatal period, the vast majority of these tumors are benign; however, a few may be malignant. This tumor is very rare with an estimated occurrence between 1 in 35,000 and 1 in 40,000 live births. It is more common in females than males with a 4:1 ratio. The cause is unknown.
A SCT is classified based on its anatomic location. Type I identifies a tumor that is completely external. Type II tumors are external with a small internal portion located in the pelvis. Type III is a mixed tumor with an external portion and a larger internal portion extending into the abdomen. Type IV is completely internal.
What testing is recommended during pregnancy?
Serial ultrasounds will follow the growth of the SCT and the health of the baby. Some babies may develop polyhydramnios (excess amniotic fluid) which may lead to premature delivery. Doppler examination is performed to assess the degree of vascularity. Some highly vascular tumors create an arterio-venous shunt and lead to heart failure and the development of hydrops (generalized body swelling). Advanced hydrops may be associated with placentomegaly and maternal "mirror syndrome" in which the mother develops total body swelling. A fetal echocardiogram is recommended to assess the baby's heart function. In some cases, a fetal MRI is helpful in determining tumor size and anatomy.
Are there special considerations for the delivery?
The birth of the baby should be planned at a hospital that is prepared for high-risk deliveries, including pediatric surgical services and a neonatal intensive care unit. Premature delivery is more common among these babies often related to polyhydramnios and the tumor size. A Cesarean section is recommended for large tumors to prevent dystocia, tumor rupture, or bleeding.
Is there fetal treatment for sacrococcygeal teratoma?
Open fetal surgery has been reserved for babies with highly vascular SCT's who develop hydrops before 30 weeks gestation. There has been success removing the tumor before birth, which allows the baby's condition to improve and prolongs the length of the pregnancy. Minimally invasive fetal surgical techniques are being developed, but thus far have met with limited success. Other options that may be available include removing some of the excess amniotic fluid around the baby.
What is the treatment for SCT?
Once the baby is stabilized, the tumor is surgically removed. The doctors will be monitoring your baby's heart function and blood pressure as large tumors contain a considerable amount of blood and vascular tumors can lead to heart failure. Once removed, the tumor will be sent to the pathology lab for analysis.
Are there other health problems that are more common among babies with SCT?
The long-term outlook for babies with SCT is usually very good. It is important to remember that even benign tumors may reoccur and the baby will require regular check-ups for at least 3 years. A blood test called a serum AFP (alpha-fetalprotein) will be scheduled routinely as a screening tool to identify tumor recurrence.
SCTs located mostly in the pelvis may affect the muscles and nerves in the pelvis, altering bowel and bladder function.
Can this happen again with another pregnancy?
There have been a few reported cases in families. Your doctor and a genetic counselor will review the risk in your family.