A solid renal mass detected during prenatal ultrasound is most likely a

Mesoblastic nephroma is the most common solid renal tumor identified in the neonatal period and the most frequent benign renal tumor in childhood. It represents 3-10% of all pediatric renal tumors. Many cases are diagnosed with prenatal ultrasound and can manifest as polyhydramnios, hydrops, and premature delivery. Most of the patients are diagnosed before 3 mo of age, whereas WT is rarely diagnosed before 6 mo of age. Radical nephrectomy is the treatment of choice and may be sufficient by itself. Local recurrence is uncommon. Reference: Nelson; Neuroblastoma; Page no: 2467