We present a child with a rare and chemotherapy-resistant form of soft-tissue cancer, low-grade fibromyxoid sarcoma, first noted when he was 4 years old. He is the youngest patient reported to date. An 11-year-old white male presented to. The University of Texas M.D. Anderson Cancer Center's Department of Pediatrics with a 7-year history of right thigh mass and pulmonary nodules, confirmed on examination. He had undergone extensive prior chemotherapy and surgery. He received chemotherapy with high-dose cyclophosphamide (7 g/m2) and later etoposide (150 mg/m2/day x 5), with only slight shrinkage of the thigh mass and none in the lungs. Subsequently the tumor in his proximal thigh and his lung metastases were resected, and radiation therapy was administered to the thigh. His disease remained stable for 12 months, but he then developed a pleural-based metastasis on the left side and new bilateral lung metastases also. The tumors on the left side were removed; residual disease is stable after treatment for 6 months with subcutaneous alpha-interferon-2b. Low-grade fibromyxoid sarcoma is very uncommon in children. It grows slowly and metastasizes to distant organs, chiefly to the lungs. It is resistant to conventional chemotherapy, and thus far only surgery seems to have a life-prolonging effect. Newer chemotherapeutic and possibly biologic agents should be tried in future patients, in order to find an effective way to control the disease.