[en] Three children with Stage IV-S neuroblastoma and massive hepatomegaly were treated with low dose radiotherapy to the liver (1200 to 1400 rad at 125 to 150 rad per day). Radiotherapy was efficacious in reducing liver size in our small series; the three patients are alive without disease at 2, 33, and 4 years, respectively, following treatment. Although all three patients are doing well, our data suggest a low threshold for radiation kidney damage in children less than 6 months old. Since treatment strategy is designed to reverse liver enlargment and not to deliver a curative dose, radiation treatment should be designed to avoid the kidneys