Outcome of prenatally diagnosed solid fetal tumors

In the last 10 years, the ability to diagnose fetal tumors in the prenatal period has improved greatly because of technical advances in imaging. Early diagnosis and determination of tumor may affect prognosis.

The authors retrospectively reviewed the records of 1316 fetuses who underwent sonographic evaluation for congenital defects at University of California-San Francisco over a 6-year period. Of these, 16 had fetal tumors and were followed up at our institution. There were solid or predominantely solid with small cystic component masses in one of 3 locations: cervical, mediastinal, or abdominal. Excluded from our study were those fetuses with either sacrococcygeal teratoma, congenital cystic adenomatoid malformation of the lung, or ovarian cyst, because these defects have been extensively reviewed elsewhere. In addition, masses that were primarily cystic also were excluded. Data collected included diagnosis, gestational age at diagnosis and at delivery, mode of delivery, fetal and neonatal survival, and disease confirmation.

Of the 16 fetuses, 4 had mediastinal tumors: 2 with pericardial teratomas (both of whom died in utero) and 2 with cardiac rhabdomyomas (1 died; the other presented tuberous sclerosis and is alive at 2 years of age). Four patients had cervical tumors (3 died; 1 survived and is alive and well), and 8 had abdominal tumors (3 with liver tumors, 4 with a left adrenal mass, and 1 with retroperitoneal teratoma). All eight patients with an abdominal tumor are alive and well.

Fetal tumors are rare, and the prognosis seems to depend on their location and size. Although easier to detect, cervical and mediastinal tumors have a worse prognosis. Abdominal masses are more difficult to detect but have a better prognosis.