Congenital cystic mesoblastic nephroma

Congenital mesoblastic nephroma is a relatively rare infantile renal tumor. It comprises 3-6% of renal masses in childhood and 50% during the neonatal period. Most mesoblastic nephroma occur in the newborn period, with 80% of the cases being reported within the first month of life, Macroscopically t he tumor is composed of a solid mass of different sizes tending to invade t he surrounding structures and renal parenchyma. The authors report a case o f cystic mesoblastic nephroma of the cellular subtype, with diffuse areas o f hemorrhage and necrosis. The tumor was treated by surgical excision with radical nephrectomy and the child is doing well 4 years after the operation .