Improvement In Renal Function In Newly Diagnosed Myeloma Improves Survival, but Still Remains Inferior to Those with Normal Renal Function
Authors: Kumar Shaji , Dispenzieri Angela , Lacy Martha , Hayman Suzanne R. , Buadi Francis , Dingli David , Detweiler-Short Kristen , Lust John , Zeldenrust Steven , Russell Stephen , Greipp Philip R. , Kyle Robert , Gertz Morie , Rajkumar Vincent 
Published: October 2019

Abstract
Abstract 2970

Background:
Over a quarter of patients (pts) with symptomatic multiple myeloma (MM) have some degree of renal insufficiency at the time of diagnosis. Multiple studies show that presence of renal failure is strong predictor of inferior overall survival in MM. With effective therapy, renal function improves in a considerable number of patients. It is not clear if the return of renal function to normal levels will improve their outcome to that expected for patients without renal dysfunction.

Methods:
We evaluated 1478 patients with newly diagnosed myeloma seen at Mayo Clinic within 90 days of diagnosis, between January 1999 and January 2009. We examined these patients for improvement in renal function and identified the lowest serum creatinine obtained during the disease course. The outcomes were analyzed with respect to the renal function improvements.

Results:
The median age at diagnosis was 64 years (range; 22–93) and 50% were male. The median estimated follow up for the entire cohort was 53 months, with 781 patients alive at the time of analysis with a median follow of 3 years. The serum creatinine was over 1.5 mg/dL at diagnosis in 333 (22.5%) pts and over 2.5 mg/dL in 148 (10%) pts. The median overall survival for the 333 patients was 37 mos (95% CI; 28, 40) compared to 56 mos (95% CI; 51, 63) for those < 1.5 mg/dL; P < 0.001. Among the 333 pts with baseline Cr > 1.5 mg/dl, any improvement in Cr was seen in 263 (79%) including an improvement of at least 0.5 mg/dL in 208 (62%) pts. Among the 263 pts with any improvement, the median time to lowest Cr was 4 months (range; 1–13). The median survival of the group of patients with Cr <= 1.5 mg/dl, over 1.5 mg/dL at diagnosis but improved to <= 1.5 mg/dL, or remained >1.5 mg/dL were 56., 40 and 27 mos respectively; P < 0.001, Figure). We then examined the impact of renal function improvement in the group of patients where the baseline Cr was >2.5 mg/dL. The median OS for the 42 (out of 148 pts with Cr > 2.5 at diagnosis) who had improved to <=1.5 mg/dL was 40 mos compared to 56 mos for those with a Cr <= 1.5 mg/dL at diagnosis and 27.4 mos for the 106 pts whose Cr did not decrease to <= 1.5 mg/dL; P < 0.001.

Conclusion:
The results of this study point toward improved outcome among patients with renal dysfunction in whom renal function improves. However, it shows that this improvement in renal function does not necessarily improve survival to that observed for the patients with a comparable level of serum creatinine at diagnosis. While early treatment of asymptomatic myeloma has been shown to have little impact on overall survival, a strategy of waiting for serious features of target organ damage to appear before initiation of treatment may have a negative impact on survival in some patients, especially patients with high light chain production who have a higher predilection for renal insufficiency.

Disclosures:
Kumar: Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Off Label Use: Lenalidomide for treatment of newly diagnosed myeloma. Dispenzieri:Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Lacy:Celgene: Research Funding.