PB2157 CHARACTERISTICS AND REAL-WORLD TREATMENT OUTCOMES IN MULTIPLE MYELOMA YOUNG PATIENTS: A SINGLE CENTER MOROCCAN EXPERIENCE
Authors: E. M. Mahtat, K. Zine Filali, S. Haidouri, S. Jennane, H. ElMaaroufi, M. Mikdame, K. Doghmi
Journal: HemaSphere (2019)

Background: The treatment of multiple myeloma (MM) has drastically changed with the increasing number of novel agents in the last decade. Moroccan real-world data on patient outcomes and treatment in MM are limited. Aims: The aim of this study is to document current clinical characteristics of newly diagnosed multiple myeloma young patiants (<65 years) and describe patient management and outcome and evaluate the influence of known prognostic factors in a real-world setting. Methods We collected retrospectively data from medical records of all young (< 65 ans) multiple myeloma patients treated in the Clinical Hematology Department of the Hôpital Militaire d’Instruction Mohamed V in Rabat-Morocco between April 2006 and January 2019. Our database included clinical characteristics, laboratory, prognostic factors, treatment indicated, treatment-related adverse events (neuropathy, thrombosis), and response to treatment. Quantitative variables were described in terms of mean, median and standard deviation; qualitative variables were described as absolute percentage for each modality. Kaplan Meier curves were used to calculate overall and progression free survivals. Log rank test was used to compare survival between different sub-groups. Results: 83 patients were included. Median age was 67 years. Sex ratio was 2,8. The median time from first symptom to consultation was 16 weeks. Bone pain was the most frequent symptom reported by 78% of the patients. Distribution according to immunoglobulin subtype was: IgG 51%, IgA 16%, Light chains 28%, non-secretor 5%. Median bone marrow plasmacytosis was 34% and median serum monoclonal protein level was 2,7 g/dl (range 0–11,3 g/dl). Anemia was found in 51% of the patients; 91% had osteolytic lesions whereas impaired kidney function was observed in 37% and hypercalcemia in 30% at the time of diagnosis. LDH were elevated in 30% of the 44 patients tested. 48% of patients had hypoalbuminemia. Most patients had advanced disease: 47% patients were stratified ISS 3. Fluorescence in situ hybridization (FISH) for del17p, t(4;14) was evaluated in 30% (n = 25), being negative in 52% and positive in 16%. First-line treatment included bortezomib in 30% of patients (28% VTD, 1% VD, 1% VCD). CTD regimen was used in 39 patients (47%). The rest of the patients were treated by conventional therapy (VAD in 17 patients and VMCP in 2 patients). Overall response (≥ PR) was obtained in 88% (n = 73). VGPR + CR = 58% and CR = 11%. Ten patients had stable disease at the end of treatment and 3 (4%) were refractory to first line therapy. Neuropathy was the most common adverse effect reported (38%) with grade 3-4 in 19% of the patients. Thromboembolic events were reported in 8 (9,5%) patients. 37% of patients received autologous stem cell transplantation (ASCT) after first line therapy. After a median follow-up of 34 months, progression free survival (PFS) was 45% and overall survival (OS). The median OS and PFS were respectivly; 65 and 39 months. The ISS score did not influence the OS and the PFS. In an univariate analysis, patients with elevated LDH, anemia, impaired kidney function and the patients that were not transplanted in first line had shorter OS and PFS. Receiving Bortezomib in the first line did not influence the OS and PFS of our patients. Summary/Conclusion: The present study is the first analysis of Moroccan young multiple myeloma patients data, and it provides important insights into the real-world management of MM in our unit. A larger national register is established, and the data will be analysed soon.