Abstract
Purpose and Methods: A case of polycythemia with a normal serum erythropoietin is described, which led to the diagnosis of Wilms tumor. The clinical features of the reported cases of Wilms tumor associated with polycythemia are reviewed. Results: An asymptomatic 6-year-old boy with polycythemia, a normal serum erythropoietin, and no evidence of erythroid colony forming activity in his serum was found to have a Wilms tumor. After resection and chemotherapy, he has had no recurrence of either the polycythemia or the Wilms tumor. There have now been 10 cases of Wilms tumor reported: 7 patients were more than 16 years of age, 8 were boys, and 9 were clinical stage 1 with a favorable histology. Conclusions: Polycythemia is a rare manifestation of Wilms tumor that can occur in the absence of an elevated serum erythropoietin and has an association with male gender, older patient age, and low clinical stage. Children with unexplained polycythemia should be investigated for Wilms tumor, even if the serum erythropoietin level is normal.