J Nucl Med 2000 Oct;41(10):1695-701
Grading of tumors and tumorlike lesions of bone: evaluation by FDG PET.
Schulte M, Brecht-Krauss D, Heymer B, Guhlmann A, Hartwig E, Sarkar MR,
Diederichs CG, Von Baer A, Kotzerke J, Reske SN.
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.
