18F-fluorodeoxyglucose (18F-FDG) has been approved by many regulatory agencies world-wide and is in widespread use in the United States, Japan and Europe. In the United States, 18F-FDG scanning in oncology is approved for federal healthcare reimbursement for non-Hodgkin's lymphoma, Hodgkin's disease, colorectal cancer, lung cancer, oesophageal cancer, melanoma, head and neck cancer and breast cancer. It has general applications in all areas where abnormal glucose metabolism may be present including in circumstances such as differentiating the tumour from scar tissue; evaluating the presence of the tumour in light of rising tumour markers and normal imaging techniques; and assessing response to therapy where other techniques are deemed to be unhelpful. Current literature suggests that functional imaging with 18F-FDG Positron Emission Tomography (PET) may play an important role in the imaging evaluation of patients with soft tissue sarcoma, including guiding biopsy; detecting local recurrence at sites of tumour resection; detecting metastatic disease; predicting and monitoring response to therapy; and assessing for prognosis. In appropriate situations, it is possibly the most effective diagnostic strategy. However, due to the low incidence of these tumours, prospective studies with large multicenter patient groups will be essential to define the exact diagnostic role of 18F-FDG PET in this clinical setting.