Outcomes of Patients With Multiple Myeloma With deletion 1p Following Autologous Stem Cell Transplant.

BACKGROUND

Several studies have suggested that a deletion in the short arm of chromosome 1 (del(1p)) is an independent adverse prognostic factor in patients with multiple myeloma (MM). However, its impact on outcomes of patients undergoing autologous hematopoietic cell transplantation (autoHCT) and receiving contemporary anti-myeloma therapy remains unclear.

STUDY

DESIGN

A retrospective, single-center analysis of newly diagnosed MM (NDMM) patients with del(1p) who underwent upfront autoHCT between 2010 and 2021. The primary endpoints were progression-free survival (PFS) and overall survival (OS). Propensity-matched comparisons were performed between del(1p) patients and a control group without del(1p) and with standard-risk cytogenetics.

RESULTS

55 patients were included in our analysis. With a median follow-up of 24.0 months (range 3.8-79.5), the median PFS was 30.2 months (95% CI 18.0-not reached [NR]) and the median OS was not reached (95% CI 41.1-NR). In multivariable analysis, female patients (hazard ratio [95% CI] 2.81 [1.14, 6.91], P = .025) and those with R2-ISS stage IV (compared with stage II 4.85 [1.01, 23.34], P = .049) had worse PFS, whereas patients who achieved CR as the best post-transplant response had better PFS (0.38 [0.16, 0.91], P = .029). Concomitant del(17p) was associated with a significantly worse OS (4.47 [1.18, 17.02], P = .028). Propensity score matching showed no significant differences in PFS (1.63 [0.86, 3.10], P = .13) or OS (1.77 [0.73, 4.32], P = .21) between del(1p) and control patients.

CONCLUSIONS

In NDMM patients undergoing upfront autoHCT, del(1p) alone was not significantly associated with inferior outcomes. However, concurrent del(17p) and del(1p) was associated with worse survival.