PB1990: MULTIPLE MYELOMA IN THE ELDERLY: A MONOCENTRIC EXPERIENCE

Background: Multiple myeloma (MM) is a common hematological malignant neoplasm and it is primarily a disease of the elderly. Development of newer therapeutic agents and improving supportive care over the last decades has significantly improved outcome of MM in younger patients. However, most studies suggest that improvements are marginal in elderly patients.

Aims: The aim of the study is to report the clinical, paraclinical and therapeutic features of the elderly multiple myeloma (age >65 years) in our center.

Methods: We retrospectively reviewed data of patients aged over 65 years diagnosed with MM and treated at the hematology department of Hedi Chaker Hospital Sfax between January 2012 and December 2019. Response to treatment is evaluated according to the International Myeloma Working Group (IMWG). these patients are considered ineligible for autologous stem cell transplantation (ASCT). The induction regimen is based on the combination melphalan-prednisone-thalidomide (MPT) or melphalan-prednisone (MP). Clinical outcomes included: reason for treatment discontinuation, overall response rate (ORR), overall survival (OS), progression-free survival (PFS), and adverse events (AE).

Results: A total of 40 patients (sex ratio M/F=1.35) were included in our study. Median age was 73 years [65-93 years]. 10 patients (25%) aged ≥80 years. Performance status (PS) was ≥2 in 29 patients (73%). sixty percent of the cases had at least one comorbidity. The median Charlson Comorbidity Index (CCI) was 4 [2–7]. Bone pain was the most common presenting complaint observed in 65% of the cases. Monoclonal IgG was the predominant protein M type’s (70%). According to the Durie-Salmon Staging System, IIIA was the main stage noted in 64% of the cases followed by IIIB in 23% of the cases.

MPT and MP regimens were received in 57% and 17/40 respectively.

ORR was 23%, including, VGPR 5 %, and PR 18%. None of the cases acheived complete remission. Stable disease occurred in 30 % and progressive disease in 7.5%. The remain cases were non evaluable (15/40). Treatment was discontinued in 14 cases (35%) after a median of 2 courses due to either progression or toxicity.

Main adverse events were infectious in 25% (10 cases) and hematological in 22% (9 patients).

Median Follow up was 77 months. Median survival was 24 months. OS and PFS were 47% and 44% at 2 years and 27% and 23% at 5 years respectively.

Summary/Conclusion: Despite the fact that one third of our patients had no comorbidity, MPT and MP regimens in our study had insufficient results and correlated with a lower ORR and median survival comparatively to the literature (24 vs 48 months). It can be explained by the low rate of patients receiving Thalidomide. The combination of bortezomib-lenalidomide-dexamethasone for elderly patients may improve our results. In addition, structured frailty assessment is required in order to devise individualized treatment plan able to improve the clinical outcomes and the Quality of life.