Impact of Dialysis Dependence on Survival for Multiple Myeloma Patients with Renal Impairment: A Multicenter Retrospective Study in China

Background: Renal impairment is a very common complication of multiple myeloma (MM) with a negative impact on survival. About 20-40% of de novo multiple myeloma suffer from renal impairment, while 10% require dialysis support. In the traditional agent era, the prognosis for dialysis dependence was very poor. But in the novel agent era, the data for survival of multiple myeloma with dialysis dependence are quite limited.

Methods: In this multicenter study, we retrospectively analyzed 337 MM patients with renal impairment at diagnosis between April 2004 to Jan 2020 from three hospitals in China. Renal impairment was defined as estimated glomerular filtration rate (eGFR) < 40ml/min and/or serum creatinine ≤ 177μmol/L. RI caused by other reasons than tubular nephropathy was excluded. Dialysis dependence was defined as dialysis support started at front-line treatment or at relapse without recovering.

Results:

Of all 337 patients, 54 patients were in the dialysis dependence group. Of patients without dialysis dependence, 42 were in the dialysis independent group, and 241 were in the without dialysis group. The baseline characteristics of the three groups are summarized in Table 1. There were significant differences in LDH and renal function among the three groups respectively and the dialysis dependence group had the highest value of both LDH and serum creatine. In cytogenetics, t(11;14) were more prevalent for dialysis dependence group compared with other two groups (24.1% vs. 11.9% vs. 14.1%, P =0.027). There were no differences in t(4;14), t(14;16), del(17p) and 1q21 gain among the three groups. The induction treatments were similar across the three groups, while dialysis dependence group had less opportunity to receive autologous stem cell transplantation compared with the remaining two groups (3.7% vs. 31% vs. 21.2%, P <0.01). The best hematologic response after the first-line treatment for dialysis dependence group was the worst among the three groups (at least VGPR, 18.5% vs. 80.9% vs. 57.7%, P <0.001). The best renal response after the first-line treatment had a similar tendency for dialysis dependence group (at least MR, 0 vs. 97.7% vs. 76.3%, P< 0.001). In addition, dialysis dependence group suffered the highest early mortality within 24 months (46.3% vs. 23.8% vs. 25.3%, P <0.01). In general, the median PFS and OS for the whole cohort were just 27 months (95% CI: 22.6-31.3 months) and 44 months (95% CI, 38.1-49.8 months) respectively. Dialysis dependence group had a similar progression-free survival (PFS) as the other two groups (27 vs. 25 vs. 28 months, P =0.214). However, overall survival (OS) was the shortest for dialysis dependence group (27 vs. 69 vs. 46 months, P =0.001). But multivariate analysis did not further confirm dialysis dependence could independently predict shorter OS.

Conclusion: In conclusion, MM with dialysis dependence is more likely to suffer early mortality within 24 months. Compared with mild or moderate renal failure, dialysis dependence seems to have no dependent negative impact on survival although the survival for the whole cohort was poor.

No relevant conflicts of interest to declare.