Background: The pathophysiology of bone malignancies has become better understood owing to the appearance of hybrid positron emission tomography/computed tomography (PET/CT) modality which has a huge influence on treatment strategies. The study aimed to clarify the supplementary benefits of PET/CT in the staging of primary bone malignancies and the assessment of post-therapeutic response.

Methods: Thirty six patients with pathologically proven primary malignant bone tumors were included in this cross-sectional prospective study. Every patient had PET/CT scan performed for staging/restaging and evaluation of therapeutic response. The gold standard reference to verify the accuracy of the study results was biopsy/histopathology.

Results: FDG-PET/CT demonstrated higher sensitivity and specificity than CT in evaluation of therapeutic response and follow-up of cases to detect residual/recurrent lesions with sensitivity 90.9%, specificity 100%, positive and negative predicative values 100% and 87.5% respectively and overall accuracy 94.4%. Meanwhile, CT sensitivity was 81.8%, specificity 71.4%, positive and negative predicative value were 81.8% and 71.4% and accuracy 77.8%.

Conclusion: As a promising non-invasive diagnostic method for evaluating primary bone malignancies; PET/CT is an imaging modality that offers a high specificity, sensitivity, and accuracy.