%0 Journal Article %A Michael Schulte %A Doris Brecht-Krauss %A Berno Heymer %A Albrecht Guhlmann %A Erich Hartwig %A Michael R. Sarkar %A Christoph G. Diederichs %A Alexandra Von Baer %A Jörg Kotzerke %A Sven N. Reske %T Grading of Tumors and Tumorlike Lesions of Bone: Evaluation by FDG PET %D 2000 %J Journal of Nuclear Medicine %P 1695-1701 %V 41 %N 10 %X Clinical diagnosis of skeletal tumors can be difficult, because such lesions compose a large, heterogeneous group of entities with different biologic behaviors. The aim of this prospective study was to assess the value of PET in grading tumors and tumorlike lesions of bone. Methods: Two hundred two patients with suspected primary bone tumors were investigated using FDG PET. Uptake of FDG was evaluated semiquantitatively by determining the tumor-to-background ratio (T/B). All patients underwent biopsy, resulting in the histologic detection of 70 high-grade sarcomas, 21 low-grade sarcomas, 40 benign tumors, 47 tumorlike lesions, 6 osseous lymphomas, 6 plasmacytomas, and 12 metastases of an unknown primary tumor. Results: All lesions, with the exception of 3 benign tumors, were detected by increased FDG uptake. Although sarcomas showed significantly higher T/Bs than did latent or active benign lesions (P < 0.001), aggressive benign lesions could not be distinguished from sarcomas. Using a T/B cutoff level for malignancy of 3.0, the sensitivity of FDG PET was 93.0%, the specificity was 66.7%, and the accuracy was 81.7%. Conclusion: FDG PET provides a promising tool for estimating the biologic activity of skeletal lesions, implicating consequences for the choice of surgical strategy. %U https://jnm.snmjournals.org/content/jnumed/41/10/1695.full.pdf