Isolated hemihyperplasia is a rare overgrowth syndrome characterized by an asymmetric regional body overgrowth, involving at least one limb, and associated with an increased risk of developing embryonal tumors, principally nephroblastoma and hepoblastoma. The disease is MONDO_0009331 (isolated hemihyperplasia). Also known as: Hemicorporal hypertrophy, hemi 3 syndrome, hemihypertrophy, isolated hemihypertrophy.