Prognostic value of baseline elevated red cell distribution width in DLBCL.

Abstract

e20031 Background: Elevated red cell distribution width (RDW) has been associated with all-cause mortality, risk of developing cancer and cancer mortality in large retrospective studies. The underlying mechanism may be due to inflammatory and nutritional abnormalities. We hypothesized DLBCL patients with an elevated RDW at the time of diagnosis would have a worse prognosis. Methods: A retrospective single-institution study included 541 DLBCL patients diagnosed between 2001 and 2016. RDW over 14.5% was considered high, as this was the upper limit of normal at our institution. The overall and progression free survival was estimated using Kaplan-Meier methods, and the difference between groups was compared using the log-rank test. Univariate and multivariate analyses were performed with Cox proportional hazards regression. Results: We identified 410 DLBCL pts with available baseline RDW, 229 (56%) had RDW > 14.5. Median follow up from diagnosis was 60 months. The complete response rate was 63.8% in the group with high RDW (n = 152) and 88.4% in the normal RDW group (n = 216, p < 0.0001) . For patients with high RDW, 1-year overall survival (OS) was 65% (95%CI 0.58-0.72) vs 90% (95%CI 0.87-0.94) for pts with normal RDW < / = 14.5; 2-year OS was 57% (95%CI 0.50-0.65) vs 84% (95%CI 0.79-0.89), respectively (p < 0.0001). This difference remained statistically significant when the analysis was restricted to patients treated with anthracycline-containing regimens given with curative intent (2y OS = 66% vs. 87.5%, p < 0.0001). Univariate analysis revealed that R-IPI, high RDW, elevated LDH, albumin < 3.5mg/dl, Hgb < 10g/dl, advanced stage disease, bulky disease, extra nodal disease, and ECOG performance status 3-4 were associated with worse OS. In multivariate analysis, older age (HR 2.07, 95%CI 1.38-3.1), high RDW (HR 1.68, 95%CI 1.15-2.5), albumin < 3.5mg/dl (HR 1.76, 95%CI 1.18-2.6) and ECOG 3-4 (HR 2.47, 95%CI 1.47-4.2) were independent prognostic factors for OS. Conclusions: High RDW is associated with worse response rates and independently associated with worse OS in patients with DLBCL. Based on our study, DLBCL patients with high RDW at diagnosis should be considered at higher risk of mortality and treatment failure. Further research is needed to clarify the underlying mechanism and to evaluate the utility of incorporating RDW into prognostic indices.