Abstract
Fetal abdominal masses can be challenging to counsel due to uncertain diagnosis and
outcomes. We report a case of a midline upper retroperitoneal mass found incidentally
during a routine third trimester ultrasound. Despite not being a suprarenal mass,
ultrasound and magnetic resonance imaging indicated neuroblastoma prenatally. With
the generally favorable prognosis for prenatally diagnosed neuroblastomas, expectant
counseling was given. Postnatal imaging and biopsy confirmed ganglioneuroblastoma,
a rare subtype. A conservative approach was taken, and after initial growth, the mass
spontaneously regressed 5 months after birth, nearly resolving by 8 months.
Keywords
antenatal - fetal - ganglioneuroblastoma - neuroblastoma - tumor
