Newborns rarely have tumors, but when they do, one of the most common types is a sacrococcygeal teratoma (SCT)—a tumor located at the base of a baby’s tailbone either inside the body, outside the body or some combination of both. Out of every 35,000 live births, sacrococcygeal tumors happen only once.
Sacrococcygeal teratomas are classified into four types, based on their location in or on a baby’s body.
- Type I grows outside the body and is visible on the baby’s butt.
- Type II grows mostly outside the body, but has a small part inside the body.
- Type III is mostly inside the body, but has a small part outside the body.
- Type IV is only inside the body.
Some SCTs are like a balloon with one or more cysts inside, each of which may contain fluid. Others are made of soft and/or solid parts, supported by blood vessels within. They are classified as part of a larger group of tumors known as germ cell tumors.
Sometimes the cells inside sacrococcygeal teratomas are cancerous. From Type I to Type IV, the risk of malignancy increases. (Eight to 10 percent of Type I tumors are malignant, compared to 38 percent of Type IV tumors.) Even when they are benign, these tumors must be treated because there is a risk that they can become malignant later.
Researchers know very little about what causes these tumors, but children typically have very positive outcomes after treatment. Between 89 and 96 percent of babies never have a tumor return, The vast majority live without any significant impact to their overall health following treatment. Even those children born with malignant tumors have a 90 percent survival rate. Our team of maternal-fetal and pediatric experts has the multidisciplinary skills to give advanced diagnosis and treatment for children with sacrococcygeal teratomas.
Diagnosis for Sacrococcygeal Teratomas
Type I tumors are often detected before birth on a prenatal ultrasound or magnetic resonance imaging (MRI). When a mother’s uterus appears larger than it should be for the baby’s stage of development, it can be a sign that a baby has a tumor, but this is not always the case. (An enlarged uterus can also be caused by excess amniotic fluid—a condition known as polyhydramnios.) Prenatal blood tests may also suggest a sacrococcygeal teratoma.
Type I sacrococcygeal tumors are quite noticeable in imaging results because they may be as large as a baby’s head, and they are located outside the body. The largest tumors may require a Cesarean section birth to make sure the tumor does not tear or rupture during delivery.
Internal tumors (Types II, III and IV) are typically small and may not be detected until after birth. They may only be discovered when a child develops stooling, continence or constipation issues as a result of an internal tumor pressing on the tailbone, the rectum and/or the urinary system.
All sacrococcygeal teratomas are a concern during pregnancy because they can steal blood supply and nutrition from an unborn baby. A tumor may interfere with the heart, causing babies to develop a condition called hydrops or heart failure. For this reason, we closely monitor these fetuses for growth and heart function.
Among the prenatal tests we use are:
- Prenatal ultrasound to examine the teratoma carefully and confirm there are no other problems with the baby
- Fetal magnetic resonance imaging (MRI) to get more information about the baby’s anatomy
- Fetal echocardiogram to assess the performance of the unborn baby’s heart
Whatever their circumstances, babies affected by sacrococcygeal teratomas should be born in a pediatric specialty hospital such as Riley at IU Health, where we have advanced skills to deliver prenatal and neonatal care, and pediatric surgery at birth.
Mothers whose babies develop hydrops (heart failure) as a result of SCT may have a set of risk factors that resemble their babies’ condition. Their symptoms may include high blood pressure, swelling of the feet and hands, protein in the urine and fluid on the lungs. Riley at IU Health is home to nationally-ranked maternal-fetal specialists who are specially trained to care for a mother and her unborn child through such high-risk pregnancies.
Type I Tumors
Type I tumors (external tumors) are usually the simplest to treat because they can often be removed during the first week of a newborn’s life. (This is true only if there are no signs of heart failure during pregnancy.) Babies affected by sacrococcygeal teratoma are assessed at birth to determine how the heart is functioning and any other impact the tumor may have on the baby. If the baby’s heart is stable, we want to remove external tumors (Type I) as soon as possible.
Pediatric surgeons usually remove the tumor and the coccyx—the tip of the tailbone. The loss of the coccyx minimizes the risk of a tumor returning and does not cause children any functional problem in life. The rectum and pelvic anatomy may be slightly stretched or malformed from the tumor’s growth in front of the tailbone and behind the rectum. Some children may need reconstructive surgery to create more normal contours, but they will probably have normal function of the colon and intestines.
After a tumor is removed, it is analyzed to determine whether it is malignant. Malignancies may require pediatric chemotherapy to prevent the spread of cancer cells to the rest of the body. Our pediatric oncologists follow an established treatment protocol, designed for a baby’s delicate body.
Children who have Type I (external tumors) and no heart-related health issues recover quickly and stay in the hospital between two and three weeks after their tumors are removed. We follow children affected by sacrococcygeal teratomas through the first five years of life to monitor them for possible recurrence.
If there are signs of distress before birth, a baby’s treatment plan may be quite different. Sometimes, maternal-fetal specialists determine that an early delivery is needed to address the tumor and prevent further danger to the heart.
Treatment options also include a surgical procedure that can protect the baby during pregnancy by interrupting the blood supply to the tumor. This procedure requires the specialized skills of a fetal surgeon and is only done at a few pediatric healthcare centers in the Midwest. Although Riley at IU Health does not yet perform this procedure, our maternal-fetal specialists do provide expert follow-up care for these challenging pregnancies. When we meet a family whose unborn baby may need such treatment during pregnancy, we coordinate their care at one of these highly-specialized centers. These decisions are usually made between 25 and 30 weeks of gestation.
Types II, III and IV tumors tend to have the most lengthy and complicated treatment plans because they are more likely to be (or become) malignant, and they can affect other organs such as the urinary tract and the spine. Unlike Type I teratomas, prenatal treatment is not an option, so babies with types II, III and IV must be born before treatment begins. Their internal tumors may affect their abdominal and pelvic anatomy, requiring additional treatment after their tumors have been addressed.
Life After Treatment
For 30 percent of kids, bowel and bladder continence may be slightly diminished early in life. These children are also more prone to constipation. Twenty percent of children born with Type IV sacrococcygeal teratomas may require further treatment to address their urinary system. At Riley at IU Health, your child will have expert pediatric follow-up care to help resolve any issues that stem from their condition at birth.
If your baby is diagnosed with a sacrococcygeal teratoma, you will have the full support of multidisciplinary team of expert healthcare providers to help you learn more about your baby’s condition and understand treatment options. We can answer questions and help you make decisions about your baby’s care. If your baby needs treatment before birth, we can guide you to highly-skilled fetal specialists who can care for your unborn child.
Key Points to Remember
Key Points to Remember
- Although they only occur once out of every 35,000 live births, sacrococcygeal teratomas (SCTs) are the most common type of tumor found in newborns.
- SCTs are located at the base of the tailbone and form as one of four basic types: Type I is outside the body; Type II grows mostly outside the body, but has a small part inside the body; Type III is mostly inside the body, but has a small part outside the body; and Type IV is only inside the body.
- In some cases, SCTs are malignant, but the majority of children survive SCTs even when they must have pediatric chemotherapy to treat their condition.
- Type I SCTs are often the most straightforward to diagnose because they can be easily seen on prenatal imaging. Types II, III and IV SCTs may be more difficult to spot until after a child is born and begins to have difficulty with constipation or continence of the bladder or bowels.
- Children born with SCTs should receive follow-up care for at least the first five years of life to make sure their tumors do not return.
- Some babies need to be treated while they are still in their mother’s womb to prevent damage to the heart caused by a tumor that steals too much nutrition and blood supply.
Support Services & Resources
Support Services & Resources
Visit the websites below to find support groups and learn more about sacrococcygeal teratoma.