Childhood cancer survivors are at risk for developing second malignant neoplasms. Very-low-dose therapeutic radiation therapy (RT) may be used to treat infants with Stage 4S neuroblastoma. We report a case of a patient who subsequently developed clear cell sarcoma of the gastrointestinal tract nearly 15 years after treatment with very low-dose therapeutic RT (4.5 Gy) for Stage 4S neuroblastoma.