¹⁸F-FDG PET/CT as an indicator of progression-free and overall survival in osterosarcoma

The aim of our study was to retrospectively evaluate whether maximum standardized uptake value (SUV _max), total lesion gylcolysis (TLG), or change therein using ¹⁸F-FDG PET/CT performed before and after initial chemotherapy were indicators of patient outcome. Methods; Thirty-one consecutive patients who underwent ¹⁸F-FDG PET/CT before and after chemotherapy, followed by tumor resection, were retrospectively reviewed. Univariate Cox regression was used to analyze for relationships between covariates of interest (SUV _max before and after chemotherapy, change in SUV _max, TLG before and after chemotherapy, change in TLG, and tumor necrosis) and progression-free and overall survival. Logistic regression was used to evaluate tumor necrosis. Results: High SUV _max before and after chemotherapy (P = 0.008 and P = 0.009, respectively) was associated with worse progression-free survival. The cut point for SUV _max before chemotherapy was greater than 15 g/mL* (P = 0.015), and after chemotherapy it was greater than 5 g/mL* (P = 0.006), as measured at our institution and using lean body mass. Increase in TLG after chemotherapy was associated with worse progression- free survival (P = 0.016). High SUV _max after chemotherapy was associated with poor overall survival (P = 0.035). The cut point was above the median of 3.3 g/mL* (P = 0.043). High TLG before chemotherapy was associated with poor overall survival (P = 0.021). Good overall and progression-free survival was associated with a tumor necrosis greater than 90% (P = 0.018 and 0.08, respectively). A tumor necrosis greater than 90% was most strongly associated with a decrease in SUV _max (P = 0.015). Conclusion: ¹⁸F-FDG PET/CT can be used as a prognostic indicator for progression-free survival, overall survival, and tumor necrosis in osteosarcoma. COPYRIGHT