Consultation with the Specialist
Wilms tumor is an important solid neoplasm in children that occurs with a frequency of 400 to 500 cases annually in the United States. It is important, therefore, for primary care physicians to be aware of the clinical presentation and associated symptoms and signs of Wilms tumor. Progress in management of this neoplasm has been outstanding, primarily because of cooperative efforts of the National Wilms Tumor Study Group. The significantly improved survival that has resulted from the Group's cooperative efforts serves as a paradigm for the management of all tumors. Presentation Wilms tumor most commonly presents as an asymptomatic abdominal mass. The average age of presentation is 3 to 4 years. This mass, which usually is located in the region of the flank, may be detected during a well-child routine physical examination. It also is not unusual for the mass to expand acutely due to hemorrhage within the tumor. This may account for discovery of the mass by the parents shortly after a recent thorough physical examination. The child also may present with abdominal pain associated with the mass due either to acute hemorrhage or to rupture of the tumor into the peritoneal cavity. Up to one third of children who have Wilms tumor may have microscopic hematuria, and in male patients, obstruction of the left spermatic vein can produce a left-sided varicocele.