congenital mesoblastic nephroma
Cancer
(con-JEH-nih-tul mez-oh-BLAS-tik neh-FROH-muh) A type of kidney tumor that is usually found before birth by ultrasound or within the first 3 months of life. It contains fibroblastic cells (connective tissue cells), and may spread to the other kidney or to nearby tissue. Congenital mesoblastic nephroma is more common in males.