Clinical implication of PET/CT and skeletal bone survey in evaluation of multiple myeloma and related monoclonal disorders.

Abstract

e18574 Background: Whole body skeletal x-ray is considered a gold standard for detecting bone lesions in patients with plasma cell disorders. PET/CT has been increasingly used but its role is yet to be defined. We conducted this study to compare the role of these two imaging modalities in evaluation of plasma cell disorders. Methods: This is single institution, retrospective study to evaluate the role of skeletal survey and PET/CT in patients with multiple myeloma, smoldering myeloma and MGUS. Patients’ records, imaging reports and subsequent management plan were reviewed and compared. Results: A total of 16 patients were reviewed. Among them, 11 patients had multiple myeloma, 2 had smoldering myeloma, and 3 had MGUS. 7/11 patients with multiple myeloma had concordant findings on skeletal survey and PET. 3 of these patients had negative skeletal surveys but had positive finding on PET/CT. PET/CT also identified plasmacytomas in 2 patients. In 2 patients with smoldering myeloma, both skeletal survey and PET/CT were negative. 2/3 patients with MGUS had lytic lesions on skeletal surveys which were not revealed by subsequent PET/CT’s. Both patients were observed without treatment and at 2 years follow up did not show disease progression. Conclusions: Our retrospective analysis showed that skeletal survey is still important for base-line evaluation of bone lesions in multiple myeloma and related monoclonal disorders. PET/CT is more sensitive for detection of bone lesions and can also detect extraosseous lesions such as plasmacytomas. Using tumor metabolic activity, PET/CT may improve diagnostic accuracy and is complementary to conventional skeletal survey. [Table: see text]