[Significance of Gene Rearrangement in Surveillance of Minimal Residual Disease after Autologous Hematopoietic Stem Cell Transplantation in Multiple Myeloma].

Objective: To investigate the value of immunoglobulin heavy chain () gene rearrangement in monitoring minimal residual disease (MRD) in multiple myeloma (MM) received autologous hematopoietic stem cell transplantation(auto-HSCT).

Methods: The clinical data of 26 MM patients who received auto-HSCT in the Department of Hematology, Wuhan First Hospital from 2018 to 2022 were collected. rearrangement was detected by multiplex PCR combined with capillary electrophoresis fragment analysis to evaluate minimal residual disease (MRD), and the outcome of the disease was analyzed statistically.

Results: Among the 26 MM patients, 18 were males and 8 were females, with a median age of 59(41-70) years. The median follow-up time after transplantation was 33 (7-52) months. Compared with the rearrangement negative group (=17), the proportion of CR and sCR of patients with rearrangement positive in bone marrow samples before auto-HSCT at 3 months after transplantation was lower （1/9 14/17）, and the duration of remission (DOR) after transplantation was shorter（10.78±4.35 15.88±5.22 months）, with statistically significant difference in DOR between the two groups( < 0.05). Compared with rearrangement negative group (=21), the proportion of CR and sCR of patients with positive rearrangement results from peripheral blood stem cell collection at 3 months after transplantation was lower（0/5 15/21）, the duration of remission (DOR) after transplantation was shorter（9.60±4.83 15.19±5.11 months）, and the difference in DOR between the two groups was statistically significant ( < 0.05). During the follow-up period, 5 patients (5/9) with positive rearrangement results in bone marrow specimens died, and all patients with negative rearrangement results survived. Four patients (4/5) with positive rearrangement results by peripheral blood stem cell samples died, while one patient (1/21) with negative rearrangement results died. In both bone marrow and peripheral blood stem cell samples, the survival time of rearrangement-positive patients after transplantation was shorter than that of rearrangement-negative patients( < 0.05). Logistic regression analysis showed that gender, disease stage, the proportion of bone marrow smear plasma cells at initial diagnosis, stem cell mobilization plan, efficacy evaluation before transplantation (≥CR and 0.05).

Conclusion: By detecting rearrangement of MM patients receiving auto-HSCT, the depth of MRD can be further evaluated, which has a certain guiding significance for the efficacy and prognosis of the disease.