Prognostic value of baseline laboratory, demographic, and anthropometric parameters and PET/CT bone involvement (number of lesions and SUVmax) in multiple myeloma

Introduction and Objective: MM is a hematologic malignancy characterized by the excessive proliferation of abnormal plasma cells in the bone marrow, leading to systemic complications such as bone damage, renal failure, anemia, and hypercalcemia. This study aims to evaluate the prognostic value of baseline PET-CT findings in patients diagnosed with MM and to investigate their impact on overall survival (OS) and progression-free survival (PFS). Additionally, the relationships between SUVmax values, the number of bone lesions, and clinical-laboratory parameters with prognosis will be analyzed, and the effects of these parameters on PFS, OS, staging classification, and risk stratification will be determined. Materials and Methods: This study is designed as a retrospective analysis. Prior to initiation, ethical approval was obtained from the Ethics Committee of Selçuk University on 27.10.2023 with decision number E-70632468-050.01.04-636564 The study included 80 patients aged 18-90 years who presented to the Hematology Clinic of Selçuk University Faculty of Medicine Hospital between 01/01/2017 and 01/10/2023. The biochemical parameters (total protein, creatinine, calcium), complete blood count (leukocyte, neutrophil, platelet), beta-2 microglobulin levels, genetic findings, bone marrow pathology results, PET/CT findings, mean survival times, progression-free survival times, baseline age, and gender of the patients were recorded. Additionally, MM subtypes, disease stage, and risk group classification were documented. Patients without PET/CT imaging at diagnosis were excluded from the study. Results: In this study, the demographic, biochemical, and clinical data of 80 MM patients were analyzed, with 60% being male and 40% female. The most common MM subtype was IgG kappa (48.75%), and bone involvement was observed in 91.25% of patients. Baseline biochemical parameters revealed elevated total protein levels in 46.25%, hypercalcemia in 26.25%, elevated creatinine levels in 41.25%, neutropenia in 8.75%, anemia in 90%, and thrombocytopenia in 22.5% of patients. The impact of MM subtypes, PET-CT findings, plasma cell percentage, and biochemical and clinical parameters on survival outcomes (PFS, OS), risk stratification, and R-ISS staging was evaluated, but no statistically significant associations were found. However, elevated creatinine levels and low hemoglobin levels were significantly associated with R-ISS staging P (0,003-0,009) , suggesting their relevance in disease classification. These findings indicate the need for further studies to better understand the prognostic value of PET-CT and laboratory parameters in MM. Conclusion: Since elevated creatinine levels and anemia were significantly associated with R-ISS staging, these parameters should be considered in disease staging. To better assess the prognostic impact of other laboratory and PET-CT findings, further prospective studies with larger patient populations are warranted. Keywords: Multiple myeloma, PET/CT, creatinine, anemia, prognosis, survival, staging, plasma cell percentage.