Clinical Relevance of PET/CT in Patients with Newly Diagnosed Multiple Myeloma

Objective: Currently, the prognosis of standardized uptake value still has no consensus. We evaluated the role of the maximum standardized uptake value (SUV) of the MM lesions and the extramedullary disease (EMD) with the highest metabolic activity on PET/CT in predicting survival of newly diagnosed multiple myeloma (MM) patients.

Methods: A total of 123 previously untreated, newly diagnosed patients were enrolled in this study, who were diagnosed at the Tianjin Medical University Cancer Institute and Hospital between September 2008 and February 2018. All patients with available PET/CT information at diagnosis were analyzed.

Results: We found that no clinical characteristics were significantly different between the pathological fracture groups. However, laboratory findings including elevated creatinine and anemia at diagnosis corresponded to osteolytic lesions at baseline PET/CT (elevated creatinine, P = 0.024; anemia, P = 0.025). Compared to SUV < 5.7 group, the proportion of patients with EMD was significantly high in the SUV ≥ 5.7 group (P = 0.046). Multivariate analysis using a Cox proportional hazards model showed that age > 65, poor treatment response and EMD positive were independent poor prognostic factors for newly diagnosed MM patients.

Conclusion: We confirm the prognostic value of EMD, as detected by PET/CT, in newly diagnosed multiple myeloma patients. Therefore, the presence of EMD in newly diagnosed MM tends to be more important than the SUV.