Main Session
Sep
30
PQA 09 - Hematologic Malignancies, Health Services Research, Digital Health Innovation and Informatics
3641 - Asymptomatic Bone Lesions in Multiple Myeloma: Risks of Progression to Skeletal-Related Events
Presenter(s)
Shannon Jiang, MD - Washington University/B-JH/SLCH Consortium, St. Louis, MO
S. J. Jiang1, Z. D. Crees2, I. English3, Y. Huang1, J. Jennings4, M. Schroeder2, M. Slade2, K. Stockerl-Goldstein2, R. Vij2, and J. C. Yang1; 1Washington University School of Medicine in St. Louis, Department of Radiation Oncology, St. Louis, MO, 2Washington University School of Medicine in St. Louis, Department of Internal Medicine, Division of Oncology, St. Louis, MO, 3Washington University School of Medicine in St. Louis, Department of Orthopaedic Surgery, Division of Musculoskeletal Oncology, St. Louis, MO, 4Washington University School of Medicine in St. Louis, Department of Radiology, Division of Musculoskeletal Radiology, St. Louis, MO
Purpose/Objective(s):
Prophylactic radiation therapy (RT) to asymptomatic bone metastases has been shown to reduce progression to skeletal related events (SRE) and hospitalizations in patients with metastatic solid tumor malignancies. Patients with multiple myeloma (MM) are more prone to bone lesions that can develop into one or more SREs. It is unknown if MM patients with asymptomatic bone lesions may also benefit from prophylactic RT. We hypothesize that MM patients may have untreated asymptomatic bone lesions present on imaging for some time before progressing to SRE and aimed to determine how long untreated lesions persist before SRE.Materials/Methods:
We evaluated patients who received palliative intent RT for MM bone lesions between 2014 and 2024 at one institution (IRB 202501039). Patient characteristics and RT prescription data were collected. Sites treated by RT were assessed retrospectively to identify initial radiographic diagnosis of bone lesion and subsequent date of SRE if present. SRE was defined as fracture or cord compression. Logistic regression models were used to identify lesions at risk for SRE.Results:
Eighty-eight patients with median age of 68 (range: 29-86) were included; 51% were female and median KPS was 80 (range: 50-100). Most common RT dose was 20Gy (range: 6-36). Sites treated included: long bones (N=32, 36.4%), spine (N=25, 28.4%), pelvis (N=17, 19.3%), skull (N=5, 5.7%), and rib (N=3, 3.4%). Thirty-three patients had newly diagnosed MM, 20 of whom had SRE present at diagnosis. Fifty-five patients had relapsed disease, 20 of whom developed SRE on follow up and then were treated with RT. On average, lesions were identified on imaging 5.0 months (range: 0.2-19.9) prior to SRE. Average time to RT after imaging diagnosis of bone lesions was 6.6 months, and average time to RT after identification of SRE was 2.5 months (6 received upfront surgery). Most SREs were fracture (N=39, 86.7%), then cord compression (N=6, 13.3%). Most common sites of SRE were spine (N=15, 36.6%) and long bone (N=15, 36.6%), then pelvis (N=4, 9.8%). A third of patients (31%) required procedural intervention and 57% required hospitalization for complications with median 10-day total length of stay. Lesions in long bones (OR 26.080, p=0.02) and spine (OR 28.930, p=0.03) had significantly increased risk of developing SRE. KPS<70 was associated with increased risk of SRE (OR 2.238, p=0.16) but was not significant. Median survival after receiving palliative RT was 4.0 years.Conclusion:
In this study, patients with MM who develop SREs had bone lesions present on imaging for months prior, presenting a possible opportunity for earlier intervention. Despite development of SREs, median survival was measured in years. Subsequent progression from asymptomatic lesion to SRE has implications on patient quality of life and health resource utilization and suggests earlier RT may warrant study.