Role of repeated F-18 fluorodeoxyglucose imaging in management of patientswith bone and soft tissue sarcoma

Aim of the study: To assess the impact of repeated F-18 FDG studies on the management of patients with bone and soft tissue (B&S) sarcomas. Material and Methods: Twenty patients with B&S tissue tumors (11 M and 9 F age 17-72 years) had 52 F-18 FDG Dual Head Coincidence Imaging (DHCI) studi es. 7 patients were followed for 6 months to 2 years clinically after remov al of the primary tumor. Thirteen patients were evaluated for suspected rec urrences. Patient's preparation, F-18 FDG injection and imaging procedure w ere done according to department protocol. Attenuation corrected images wer e interpreted visually by 3 trained physicians. Tumor to background ratios were calculated for all lesions. Results: In 13 patients having both studies, baseline FDG and CT/MRI were c oncordant in 8 patients, FDG defected more lesions in 3 patients but it did not detect 4 metastatic pulmonary nodules in 2 patients. Follow up studies showed stable disease in 10 patients while 6 patients who showed worsening disease needed to change their chemotherapy. Surgery was avoided in 2 pati ents and 2 patients showed improved response. Conclusion: Repeated F-18 FDG DHCI examinations proved to have an impact on the clinical management of patients with malignant bone and soft tissue sa rcoma. It helps to differentiate postoperative changes from local recurrenc e.