[Renal lymphangioma: report of a case].

Renal lymphangioma is a very rare benign tumor caused by failure in the development of the lymphatic communication system. Since December 1997, a 55-year-old man with chronic B-type virus hepatitis has been followed at our hospital. Neither kidney showed any sign of cysts at that time. In November 2000, ultrasound sonography showed a right renal simple cyst measuring 1.0 cm in diameter. Thereafter, the initial cyst increased to 5.5 cm and numerous right renal cysts, appearing similar to multilocular renal cysts, were detected in December 2004. Computed tomography demonstrated a right renal multilocular cystic tumor, 5.5 cm in diameter, which was enhanced by contrast medium. Radical nephrectomy was performed, and the pathological diagnosis was renal lymphangioma based on positive staining with D2-40 antibody, which is reactive to endothelial cells of the lymphatics.