Response to neoadjuvant chemotherapy is 1 of the most powerful prognostic factors for extremity osteosarcoma. [F-18]-fluorodeoxy-D-glucose-positron emission tomography (FDG-PET) is a noninvasive imaging modality that is used to predict histopathologic response. To determine the prognostic value of FDG-PET response for progression-free survival (PFS) in osteosarcoma, the authors of this report reviewed the University of Washington Medical Center experience. ⋯ FDG-PET imaging of extremity osteosarcoma was correlated only partially with a histologic response to neoadjuvant chemotherapy. An SUV2<2.5 was associated with improved PFS. Future prospective studies are warranted to determine whether FDG-PET imaging may be used as a predictor of outcome independent of initial disease stage.
Douglas S Hawkins, Ernest U Conrad, James E Butrynski, Scott M Schuetze, and Janet F Eary.
Department of Pediatrics, Seattle Children's Hospital, and Department of Orthopedics, University of Washington, Seattle, Washington 98105-0371, USA. doug.hawkins@seattlechildrens.org
Cancer. 2009 Aug 1; 115 (15): 3519-25.
BackgroundResponse to neoadjuvant chemotherapy is 1 of the most powerful prognostic factors for extremity osteosarcoma. [F-18]-fluorodeoxy-D-glucose-positron emission tomography (FDG-PET) is a noninvasive imaging modality that is used to predict histopathologic response. To determine the prognostic value of FDG-PET response for progression-free survival (PFS) in osteosarcoma, the authors of this report reviewed the University of Washington Medical Center experience.MethodsForty patients with extremity osteosarcoma were evaluated by FDG-PET. All patients received neoadjuvant and adjuvant chemotherapy. FDG-PET standard uptake values (SUVs) before neoadjuvant chemotherapy (SUV1) and after neoadjuvant chemotherapy (SUV2) were analyzed and correlated with histopathologic response.ResultsThe median SUV1 was 6.8 (range, 3.0-24.1), the median SUV2 was 2.3 (range, 1.2-12.8), and the median SUV2 to SUV1 ratio (SUV2:1), was 0.36 (range, 0.12-1.10). A good FDG-PET response was defined as an SUV2<2.5 or an SUV2:1or=2.5; P=.021). Both the initial disease stage and the histologic response were associated with outcome.ConclusionsFDG-PET imaging of extremity osteosarcoma was correlated only partially with a histologic response to neoadjuvant chemotherapy. An SUV2<2.5 was associated with improved PFS. Future prospective studies are warranted to determine whether FDG-PET imaging may be used as a predictor of outcome independent of initial disease stage.Copyright (c) 2009 American Cancer Society.