Sacrococcygeal teratoma (SCT) is an unusual tumor that, in the newborn, is located at the base of the tailbone (coccyx). This birth defect is more common in female than in male babies. Although the tumors can grow very large, they are usually not malignant (that is, cancerous). They can usually be cured by surgery after birth, but occasionally cause trouble before birth.
SCT is usually discovered either because a blood test performed on the mother at 16 weeks shows a high alpha fetoprotein (AFP) amount, or because a sonogram is done because the uterus is larger than it should be. The increased size of the uterus is often caused by extra amniotic fluid, called polyhydramnios. The diagnosis of SCT can be made by an ultrasound examination.
Most fetuses with sacrococcygeal teratoma do well with surgical treatment after birth. These tumors are generally not malignant. Babies with small tumors that can be removed along with the coccyx bone after birth can be expected to live normal lives. They will need to be born in a hospital with pediatric surgeons and a specialized nursery. After hospital discharge, it is our practice to follow children who have had an SCT resection closely. We recommedn oncology and pediatric surgeon followup with bloodtesting of alpha-fetoprotein (AFP) during early childhood.
Fetuses with larger tumors or tumors that go up inside the baby’s abdomen will require more complex surgery after birth, but in general do well. Again, they will have to be followed with blood tests for several years. Fetuses with very large tumors, which can reach the size of the fetus itself, can pose a difficult problem both before and after birth.
We have found that those SCTs that are largely cystic (fluid-filled) generally do not cause a problem for the fetus. However, when the SCT is made up of mostly solid tissue, and has a lot of blood flow in it, the fetus can suffer adverse effects. This is because the fetus’s heart has to pump not only to circulate blood to its body, but also to all the blood vessels of the tumor, which can be as big as the fetus. In essence, the heart is performing twice its normal amount of work. The amount of work the heart is doing can be measured by fetal echocardiography. This sensitive test can determine how hard the heart is working when the fetus is approaching heart failure. If hydrops does develop, usually in solid rapidly growing tumors, the fetus usually will not survive without immediate intervention before birth.
Fetuses with large tumors and a great deal of blood flow to the tumor have to be followed closely for the development of hydrops, or fetal heart failure which can lead to fetal death. If hydrops does not develop, these babies may require Cesarean-section delivery and extensive operation after birth. Most babies will do well once the tumor is completely removed. Blood testing for alpha-fetoprotein (AFP) levels should be performed routinely. There can also be long-term consequences which include the reoccurance of the tumor or difficulty with urination as a consequence of the surgical procedure. Your child should be followed by an oncologist and pediatric surgeon in early childhood.
In cases with extreme fetal hydrops, the mother may be at risk for maternal mirror syndrome, which is a condition where the mother's condition mimics that of the sick fetus. Because of a hyperdynamic cardiovascular state, the mother develops symptoms that are similar to pre-eclampsia and may include vomiting, hypertension, peripheral edema (swelling of the hands and feet), proteinuria (protein in the urine), and pulmonary edema (fluid in the lungs). Despite resection of the fetal SCT, maternal mirror syndrome may still occur.
In order to determine the severity of your fetus's condition it is important to gather information from a variety of tests and determine if there are any additional problems. These tests along with expert guidance are important for you to make the best decision about the proper treatment.
The severity of sacrococcygeal teratoma is directly related to the size of the tumor and the amount of blood flow to the tumor. Both the size and the blood flow can now be accurately assessed by sonography and echocardiography. Small or medium-sized tumors without excessive blood flow will not cause a problem in the fetus. These babies should be followed with serial ultrasounds to make sure the tumor does not enlarge or the blood flow does not increase. They can be then delivered vaginally near term, and the tumor removed after birth.
Very large tumors are prone to develop excessive blood flow, which causes heart failure in the fetus. Fortunately, this is easy to detect by ultrasound. These babies need to be closely followed for the development of excess fluid in the abdomen (ascites), in the chest (pleural effusion), around the heart (pericardial effusion), or under the skin (skin edema). It is the extra blood flowing to the tumor that strains the fetal heart enough to cause heart failure(hydrops).
Mother tells the story of her experience of the diagnosis of SCT, and the care in the ICN.
Baby Sarah Elizabeth has a very successful recovery from an SCT which is removed while she is still a fetus.
During the scan the ultrasound technician discovered a mass at the base of the baby's tailbone...