How is sacrococcygeal teratoma evaluated?
Sacrococcygeal teratoma may be detected in utero with US or via fetal MRI. Because the mass may be cystic, the differential diagnosis may include a meningocele (outpouching of meninges through a defect in the posterior elements of the lumbosacral spine). High-output cardiac failure caused by a teratoma may result in hydrops fetalis, placentomegaly, and polyhydramnios, which may necessitate cesarean section or fetal surgery. MRI may be useful in the evaluation of these masses because the prognosis and surgical approach may depend on which components of the mass are within the abdomen and pelvis. Lesions confined to the true pelvis tend to be histologically benign, whereas lesions that extend beyond the confines of the sacrum tend to be malignant.