P-374: Real World Analysis Over 15 Years of Newly Diagnosed Multiple Myeloma in China

Introduction: Multiple myeloma (mm) is the second most common hematopoietic malignancy. Although the disease remains incurable at present, significant advancements in precise diagnostic techniques and prognostic stratification systems over the past decade have led to substantial evolution in treatment approaches for MM. These advancements have substantially prolonged patient prognosis and have even made the possibility of "functional cure" achievable for patients.

Methods: From 2003 to June 2021, a total of 2340 patients with MM were treated at the Lymphoma and Myeloma Department of our hospital. After screening, 1142 patients who were initially diagnosed and received regular treatment at our hospital were included in the study. We conducted a retrospective analysis of their clinical characteristics, disease staging, treatment regimens, and outcomes. In this study, high-risk cytogenetic abnormalities (HRCA) were defined as the presence of t(4;14), t(14;16), del(17p), or 1q21 abnormalities detected by FISH.

Results: From 2003 to June 2021, a total of 1142 MM patients were initially diagnosed and received regular treatment at our hospital. This period was divided into four groups: 2003-2007, 2008-2012, 2013-2017, and 2018-2021, with patient numbers of 64, 185, 466, and 427 respectively. The median age of the patients was 58 years, with a slightly higher number of male (59.8%) compared to females (40.2%). The main M protein subtype was IgG (48%), followed by IgA (23.5%) and light-chain type (19.7%). The proportion of patients with HRCAs was 31.6%. First-line induction therapies were categorized as Chemo-based, IMIDs-based, PIs-based, PIs+IMIDs-based, and CD38-included. With the introduction of new drugs, the proportions of patients receiving PIs+IMIDs-based and CD38-included regimens increased over time, reaching 62.5% and 5.2% respectively during 2018-2021. The overall proportion of patients undergoing first-line ASCT was 42.5%. With the development of treatment regimens, the prognosis of patients have shown remarkable improvements. The proportion of patients achieving deep remission (≥CR) reached 67.2% during 2018-202. Up to July 2023, the median follow-up time for the cohort was 61.6 months, with median PFS and OS of 35.5 months and 88.3 months, respectively. Cox regression analysis incorporating patient gender, age, ISS stage, LDH level, presence of HRCA, first-line treatment regimen, and whether first-line transplantation was performed revealed that ISS stage III, HRCA, high LDH levels, use of PI+IMIDs, and transplantation were independent prognostic factors.

Conclusions: Overall, this study illustrates the evolution of multiple myeloma treatment at a single center in China over nearly two decades, highlighting significant improvements in patient outcome and prognosis.