P-147: Obtaining M protein immune reconstitution as soon as possible after Tandem autologous hematopoietic stem cell transplantation improves the prognosis of patients with Newly diagnosis multiple myeloma

Introduction: In the era of new drug therapy, autologous hematopoietic stem cell transplantation after induction therapy is the standard of care for patients with multiple myeloma, and Tandem autologous hematopoietic stem cell transplantation is a treatment option to improve the prognosis of patients with high-risk cytogenetics, and obtaining M protein immune reconstitution as soon as possible after double transplantation can further improve the survival of such patients.

Methods: A total of 12 patients with newly diagnosed multiple myeloma diagnosed from June 1, 2019 to April 30, 2021 at the First Affiliated Hospital of Sun Yat-sen University were included, and all patients underwent tandem autologous hematopoietic stem cell transplantation after induction therapy containing bortezomib, and the prognostic survival of patients who obtained M-protein reconstitution after transplantation was analyzed

Results: 58.3% (7/12) of patients obtained M protein immune reconstitution after Tandem transplantation, the most common type of M protein was IgG-type M protein, the median time to obtain M protein immune reconstitution was 3 months (2-9 months) after Tandem transplantation, the median duration of reconstitution was 3 months (3-6 months), and all patients were R-ISS stage II-III, 83.3% (10/12) of patients had high-risk cytogenetics, all patients achieved at least VGPR efficacy after transplantation, with a higher CR rate in the M protein immune reconstitution group (71.4% vs 60.0%, P=0.679), although not statistically significant, and a median survival time of 2 years in the immune reconstitution group

Conclusions: Tandem transplantation is a treatment option to improve prognosis in patients with high-risk cytogenetic multiple myeloma, and patients who received M protein immune reconstitution after Tandem transplantation significantly improved survival time.