Isolated hemihyperplasia in an infant: an overlooked sign for Wilms tumor development

Children with overgrowth syndromes including isolated hemihyperplasia have an increased risk for developing embryonal tumors, particularly Wilms' tumor and hepatoblastoma. Screening with sonography has been suggested as a method of identifying these tumors while they are still at an early stage. We describe an infant diagnosed with Wilms tumor in whom isolated hemihyperplasia had been overlooked by several physicians prior to the tumor diagnosis. We recommend tumor surveillance for all patients with Beckwith-Wiedemann syndrome and isolated hemihyperplasia at least for the first six years of life since full molecular characterization of every patient is not readily available