Diagnosis of a fetal mesoblastic nephroma by 3D-ultrasound

We report a case of a fetal renal tumor detected prenatally on 3D-ultrasound. As the lesion was well encapsulated the initial sonographic diagnosis was that of a nephroblastoma. Volume calculation by the 3D technique gave a reliable estimation of the tumor size. Contrary to all published case reports concerning antenatally diagnosed mesoblastic nephromas, there was no polyhydramnios. Elective delivery was performed by Cesarean section at 38+ weeks gestation. The neonate underwent left nephrectomy on the second day of life. The subsequent course was uneventful without recurrence of the tumor.