C-reactive protein levels, the prognostic nutritional index, and the lactate dehydrogenase-to-lymphocyte ratio are important prognostic factors in primary central nervous system lymphoma: a single-center study of 223 patients

Abstract

Primary central nervous system lymphoma (PCNSL) is a rare and highly aggressive type of extranodal non-Hodgkin lymphoma (NHL), and the prognosis is poor. Currently, the most used prognostic models are the Memorial Sloan-Kettering Cancer Center (MSKCC) and International Extranodal Lymphoma Study Group (IELSG) scores; however, their predictive effects are changing with increasing incidence and changing treatment regimens. A growing body of evidence has demonstrated that inflammatory and nutritional markers are factors that can determine tumor prognosis. Therefore, the aim of this study was to identify and validate novel prognostic factors for PCNSL. Clinical information was collected from 223 patients with PCNSL. Patients younger than 18 years of age were excluded. Progression-free survival (PFS) and overall survival (OS) were used as endpoints, and receiver operating characteristic (ROC) curve analyses were conducted to determine the cutoff values for the inflammatory indicators. Correlations between variables and PFS or OS were assessed using univariate and multivariate analyses, and positive indicators were selected for survival analysis. A prognostic nutritional index (PNI) < 49.38 was associated with worse PFS (p = 0.003), and outcomes significantly differed between patients with a PNI ≥ 49.38 and < 49.38 (p < 0.001). Age < 60 years (p < 0.001) and C-reactive protein (CRP) levels < 3.14 (p = 0.001) were associated with better OS. In elderly patients (≥ 60 years), a lactate dehydrogenase-to-lymphocyte ratio (LLR) < 95.69 (p = 0.021) was associated with better OS, and the outcome significantly differed between patients with an LLR ≥ 95.69 and LLR < 95.69 (p = 0.015). The PNI and CRP levels are prognostic factors for PCNSL, and CRP was the first time shown to be a prognosis factor of PCNSL. In elderly patients with PCNSL, the LLR can predict prognosis.

Keywords: C-reactive protein; Elderly patients; Lactate dehydrogenase-to-lymphocyte ratio; Primary central nervous system lymphoma; Prognostic factor; Prognostic nutritional index.

Fig. 1

ROC curves and Kaplan–Meier survival curves of PFS and OS. NLR (p = 0.024), LLR (p = 0.035), and PNI (p = 0.001) were statistically significant on the ROC curve of PFS (a). CRP level (p = 0.008), NLR (p < 0.001), LLR (p = 0.004), dNLR (p = 0.005), SIRI (p = 0.022), SII (p = 0.017), and PNI (p = 0.001) were statistically significant on ROC curve of OS (b). Kaplan–Meier survival curves of PFS demonstrated that PNI was associated with PFS (p < 0.001) (c). In patients younger than 60 years, those with a CRP level < 3.14 mg/L exhibited better OS than those with a CRP level ≥ 3.14 mg/L (p = 0.009) (d). While no significant difference was observed between the two groups in patients aged 60 years or older (p = 0.097) (e)

Fig. 2

ROC curve and Kaplan–Meier survival curve of OS in elderly patients (age ≥ 60 years). CRP level (p = 0.047), LLR (p = 0.027), and PNI (p = 0.022) were statistically significant on ROC curve of OS (a). Kaplan–Meier survival curves of OS demonstrated that LLR was associated with OS in elderly patients (p = 0.015) (b)