The Children's Hospital of Philadelphia
What Families and Physicians Should Know About Teratomas — Prenatal Monitoring
N. Scott Adzick, MD: Teratomas are mischief makers for two basic reasons -- one is the location and the size; the size can compress adjacent developing organs, the airway in the neck or intra-abdominal structures for sacrococcygeal teratomas that grow into the abdomen. They can also have consequences in terms of their blood supply. If they're solid and richly supplied with blood, that tumor, that teratoma tumor, can steal blood away from the developing fetus and placenta and cause cardiovascular failure.
Jack Rychik, MD: The solid portion of the tumor is relatively well vascularized.
Alan W. Flake, MD: So what it is comprised of is a circuit, an abnormal circuit of blood flow, that flows through the tumor instead of through the placenta or through the fetus's tissues, and we call that a "vascular steal."
N. Scott Adzick, MD: The richly vascular tumors has blood vessels that have minimal resistance.
Alan W. Flake, MD: Because the teratoma has lower resistance for blood flow than the fetal tissues door the placenta, they will tend to steal more and more blood flow other time.
N. Scott Adzick, MD: These findings are important to follow extremely closely by serial sonography and by fetal echocardiography.
Lori J. Howell, RN: The fetal echocardiograms that are performed in an ongoing way tell us the degree of heart failure or how hard the heart is working.
N. Scott Adzick, MD: Heart failure in the fetus equals hydrops. The findings of hydrops are straightforward to see by maternal-fetal ultrasound because there is an accumulation of fluid in the body cavities of the fetus.
Alan W. Flake, MD: Fluid around the lungs, fluid around the heart, fluid in the skin, and other organs.
N. Scott Adzick, MD: That fluid can accumulate in the placenta as well which has maternal health consequences such as the maternal mirror syndrome.
Alan W. Flake, MD: And that's the syndrome where the maternal physiology begins to look like the fetal physiology.
N. Scott Adzick, MD: These mothers can become incredibly sick, require transfer to the intensive care unit, require even intubation, because the fetal problem has caused issues with maternal health.
Mark P. Johnson, MD: So really the only treatment is delivery of the baby. And you're forced into that situation no matter what the gestational age is.
N. Scott Adzick, MD: The main way to prevent fetal hydrops from occurring or, at least not to be surprised by the findings, is to monitor the maternal-fetal unit extremely closely.
Alan W. Flake, MD: We've followed patients as often as three times a week with complete imaging and measuring of cardiac output and other parameters just to try to detect the onset of high output physiology, or hydrops, as early as possible.
Mark P. Johnson, MD: If it looks like the baby is going into high output heart failure, we can either deliver the baby at an earlier gestational age to allow treatment with the baby out of the uterus or, in some rare cases, we are forced to try to deal with the tumor before birth with fetal surgery.
Alan W. Flake, MD: Because hydrops is uniformly lethal to the fetus, it's one indication that we feel comfortable offering fetal surgery for.
Mark P. Johnson, MD: We actually partially deliver the baby, take a portion of the tumor off that we can, safely. And then put the baby back in the uterus and try to get as many weeks as we can before the mom goes into preterm delivery or ruptures membranes or some other thing occurs that requires us to deliver the baby.
Alan W. Flake, MD: Teratomas can also cause trouble just from their sheer bulk and size.
Mark P. Johnson, MD: It's a volume, space-occupying mass within the uterus. And it can get so big that it fools the uterus into thinking it's time to go into labor and deliver.
Alan W. Flake, MD: And so if you have a patient with a very large cystic teratoma that's threatening preterm labor because of tumor bulk, you might actually consider draining the fluid out of the tumor.
N. Scott Adzick, MD: Sort of like a fancy amniocentesis where you remove fluid for the cyst to decrease the tumor size.
Alan W. Flake, MD: Another manifestation of teratomas can be polyhydramnios.
Mark P. Johnson, MD: Polyhydramnios is just too much amniotic fluid.
Alan W. Flake, MD: Fetuses produce amniotic fluid by peeing and they reduce amniotic fluid by swallowing. So if you interfere with either of those mechanisms, it impacts amniotic fluid quantity.
Mark P. Johnson, MD: And too much amniotic fluid causes the uterine cavity to expand to get much bigger than it should be, and the uterus can be fooled into thinking it's time to go into labor.
N. Scott Adzick, MD: Sometimes this can be managed in the symptomatic mother with polyhydramnios with amnioreduction.
Alan W. Flake, MD: Taking off amniotic fluid with a needle and trying to reduce the size of the uterus and the likelihood of preterm labor.
Mark P. Johnson, MD: Starting the patient on medication that reduces blood flow to the baby's kidneys, that limits the amount of urine that the baby produces and makes management of the polyhydramnios easier so that we don't have to repeatedly go in with needles and draw the fluid off.
Alan W. Flake, MD: Another one of the detrimental manifestations of an SCT or any teratoma is its potential for rupture.
N. Scott Adzick, MD: -- which is almost invariably fatal. The fetus bleeds to death.
Alan W. Flake, MD: And that can occurs pontaneously before birth.
Mark P. Johnson, MD: And there's no way to predict that event.
Alan W. Flake, MD: Or it can occur at the time of birth and that's one of the real risks associated with SCT that requires special attention and care to prevent.
Mark P. Johnson, MD: So even when things are going good, the baby is developing great, everything seems to be on track, we could still get blindsided by these tumors and that's why, perhaps, we are so focused on following them.