Mô mềm khối u ở trẻ em ( | Pediatric Soft-Tissue Tumors Kamran Aflatoon DO Albert J. Aboulafia MD FACS Edward F McCarthy Jr MD Frank J. Frassica MD and Alan M. Levine MD Abstract Soft-tissue tumors in children 18 years are a heterogeneous group of lesions. Masses may be asymptomatic or associated with pain or discomfort. Although most lesions are benign developing an appropriate differential diagnosis requires knowledge of the clinical and radiographic characteristics of tumors and tumorlike conditions in children. A thorough history and physical examination followed by appropriate imaging studies when indicated can establish a correct diagnosis and help determine appropriate treatment recommendations. J Am Acad Orthop Surg 2003 11 332-343 Soft-tissue tumors in children represent a heterogeneous group of lesions. The mass may be congenital traumatic inflammatory benign neoplastic or malignant neoplastic. Benign lesions may have limited growth such as a lipoblastoma or they may be aggressive such as a desmoid tumor or extra-abdominal fibromatosis. Approximately 6 000 new cases of soft-tissue sarcoma are diagnosed each year in adults compared with 600 in children 18 years 1 2 or five to nine cases per million children Soft-tissue sarcomas are the fifth most common pediatric malignancy 4 after leukemia 31 central nervous system tumors 18 lymphoma 12 and neuroblastoma 8 .4 In a review of more than 900 benign and malignant soft-tissue tumors in patients in the rst two decades of life Kransdorf5 6 found that approximately 30 were vascular 15 were neurogenic and 14 were broblastic and myo broblastic or were myogenic. Certain soft-tissue tumors occur more commonly in speci c age groups and some in certain locations. For instance malignant fibrous histiocytoma is the most frequent soft-tissue sarcoma in adults whereas most types of tumor other than fibro-histiocytic and lipocytic are more common in children than in adults7 Table 1 . Compared with those of adults pediatric sarcomas usually
