Image-Guided Radiation Therapy in Treating Patients With Primary Soft Tissue Sarcoma of the Shoulder, Arm, Hip, or Leg

DISEASE CHARACTERISTICS: * Histologically confirmed primary soft tissue sarcoma of the upper extremity (including shoulder) or lower extremity (including hip) * Incisional or core biopsy required within the past 8 weeks * No histopathological diagnosis of any of the following: * Rhabdomyosarcoma * Extraosseous primitive neuroectodermal tumor (PNET) * Soft tissue Ewing sarcoma * Osteosarcoma * Kaposi sarcoma * Angiosarcoma * Aggressive fibromatosis (desmoid tumor) * Dermatofibrosarcoma protuberans * Chondrosarcoma * Extraskeletal myxoid chondrosarcoma allowed * Tumor must be surgically resectable, as determined by a surgeon within the past 8 weeks * Limb-preservation surgery alone would not provide adequate local control, as determined by the surgeon * No sarcoma of the hand, foot, head, neck, or intra-abdominal or retroperitoneal region or body wall * No sarcoma ≥ 32 cm in any direction * No lymph node or distant metastases, according to the following within the past 8 weeks: * History/physical examination, including a detailed description of the location, size, and stage of the sarcoma * MRI with contrast of the primary tumor * The maximum dimension of the primary tumor is measured in MRI images * CT scan of the chest * Multiple pulmonary nodules \< 8 mm without a histological diagnosis detected incidentally on a non-screening CT scan may be allowed * CT scan with contrast of the abdomen and pelvis in patients with intermedia…