PET Scan Combined With CT Scan in Evaluating Treatment Response in Patients Undergoing Treatment for Bone Cancer or Soft Tissue Sarcoma

OBJECTIVES: * Determine whether an FDA-approved device that combines fludeoxyglucose \^18F positron-emission tomography (FDG-PET) and CT scanning (FDG-PET/CT) can accurately locate and determine the extent of disease in patients who are undergoing treatment for bone or soft tissue sarcoma. * Determine whether FDG-PET/CT scanning is effective in evaluating the response of sarcoma to treatment. * Determine whether the new FDG-PET/CT device improves the ability to evaluate treatment response early and accurately. * Correlate changes in glucose metabolic activity early and late after treatment with overall and progression-free survival. * Correlate changes in glucose metabolic activity early and late after treatment with degree of tumor necrosis at the time of surgery. OUTLINE: This is a prospective, pilot study. Patients are stratified according to disease (high-grade soft tissue sarcoma vs low-grade soft tissue sarcoma vs osteosarcoma). Patients undergo fludeoxyglucose \^18F positron-emission tomography (FDG-PET)/CT scanning at baseline and then within 2 weeks and 12 weeks after the start of treatment (total of 3 scans). PROJECTED ACCRUAL: A total of 120 patients will be accrued for this study.