Objective To investigate the correlation between ¹⁸F-fluorodeoxyglucose (FDG) PET/CT imaging findings and high-risk cytogenetic abnormalities (HRCA) in patients newly diagnosed with multiple myeloma (MM), and the value of both combined applications in evaluating the prognosis of patients with MM.

Methods The clinical and imaging data of 44 patients with MM diagnosed by bone marrow histopathology and laboratory examination and who underwent ¹⁸F-FDG PET/CT imaging before treatment in Shantou Central Hospital from June 2016 to November 2020 were retrospectively analyzed, including 23 males and 21 females, aged 38–91 (61.1±9.6) years old. Patients were divided into the HRCA group and the non-HRCA group according to the result of fluorescence in situ hybridization. Patients were divided into stage Ⅰ+Ⅱ group and stage Ⅲ group according to the Revised-International Staging System (R-ISS) issued by the International Myeloma Working Group. Patients were divided into two groups, a standard-risk group, and a high-risk group according to the Mayo Stratification of Myeloma and Risk-adapted Therapy (mSMART) 3.0 risk stratification criteria. Through the analysis of the ¹⁸F-FDG PET/CT imaging data, patients were divided into ≤3 groups and >3 groups according to the number of focal lesions (FLs), divided into ≤4.2 groups and >4.2 groups according to maximum standardized uptake value (SUV_max), divided into extramedullary disease (EMD) group and non-EMD group according to the presence of EMD lesions, respectively. Gather data on progression-free survival (PFS) and overall survival (OS) begins from the first follow-up. Imaging findings with clinical features, HRCA, and prognostic stages were compared using the χ² test. The independent risk factors of HRCA and stages were analyzed using the multivariate logistic regression analysis. The differences between PFS and OS among the groups were compared using the Kaplan-Meier method and Log-rank test. The independent risk factors of PFS and OS were analyzed using the Cox proportional hazards regression model.

Results FLs≤3 or >3 varied among groups of R-ISS, mSMART 3.0, and HRCA (χ²=4.919, 8.472, 8.167; all P<0.05). EMD or non-EMD varied among groups of mSMART 3.0 and HRCA (χ²=4.061, 6.808; both P<0.05). FLs>3 were independent risk factors for HRCA, R-ISS, and mSMART 3.0 (OR=10.952, 5.000, 10.714; 95%CI: 1.195–100.393, 1.127–22.181, 2.269–50.598; all P<0.05). PFS and OS varied among groups of EMD and HRCA (PFS: χ²=8.572, 9.023; both P<0.01 and OS: χ²=6.030, 4.877; both P<0.05). EMD was an independent poor prognosis factor for both PFS and OS (OR=4.466, 6.520; 95%CI: 1.084–18.396, 1.174–36.211; both P<0.05). HRCA was an independent poor prognosis factor for PFS (OR=8.458, 95%CI: 1.671–42.812, P<0.05). By the end of follow-up, patients without EMD and HRCA or only one of them had not reached median PFS and median OS; median PFS for patients with both EMD and HRCA was 11 months (χ²=20.903, P<0.001) and median OS were 17 months (χ²=10.656, P<0.01).

Conclusion There is a significant correlation between ¹⁸F-FDG PET/CT imaging findings and HRCA in patients newly diagnosed with MM, and the combination of both has a certain predictive value for the prognosis of patients with MM.