Fetal brain tumors
Fetal brain tumors are uncommon and tends to have very different pathological spectrum than that observed in adults; in order of decreasing frequency:
- fetal intracranial teratoma: most common tumor by far
- astrocytoma/glioblastoma: next most common
- craniopharyngioma: papillary type
- primitive neuroectodermal tumor (PNET)
- choroid plexus papilloma
- meningeal tumors
- meningeal sarcoma
- ependymoma
- intracranial lymphangioma
Clinical presentation
Many present late in pregnancy (i.e in the 3 trimester ).
Radiographic features
Antenatal ultrasound
Ultrasound has only a limited role in diagnosing the specific histological sub-type but has overall high detection rate . Generally speaking, many fetal intracranial tumors have the following sonographic features:
- echogenic and semi-cystic space occupying lesion with or without distortion of normal symmetrical intracranial (usually midline) structures
- fetal intracranial calcification
- fetal hydrocephalus
- macrocephaly
- presence of other associated structural anomalies
- polyhydramnios
Additional features include:
- high-output cardiac failure (hydrops fetalis)
- abnormal cerebral Doppler flow velocimetry
Treatment and prognosis
While prognosis for individual lesion can somewhat vary, intracranial tumors in general carry a poor prognosis in fetal population.