Low Prognostic Nutritional Index Correlates with Worse Survival in Patients with Advanced NSCLC following EGFR-TKIs

ObjectiveThis study was designed to demonstrate the prognostic value of prognostic nutritional index (PNI), a reflection systemic immunonutritional status, on the long-term survival of patients taking epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs).MethodsIn this retrospective study, eligible advanced NSCLC patients with sensitive EGFR mutations (exon 19 deletion or L858R in exon 21) were included to investigate the correlation between the PNI and overall survival (OS). The PNI was calculated as 10 x serum albumin value (g/dl) + 0.005 x peripheral lymphocyte count (per mm3). The prognostic significance of PNI and other clinicopathologic factors was identified by univariate and multivariate analysis.ResultsFinally, 144 patients met the inclusion criteria. The optimal cut-off value of PNI for survival stratification was 48.78. Compared with high PNI group (n = 81), low PNI (n = 63) was significantly associated with elevated C-reactive protein (CRP) level and non-response to TKIs. Overall survival was superior in the high PNI group (HR, 0.44, p = 0.004), especially for patient with L858R (HR, 0.37, p = 0.009) rather than 19 deletion (HR, 0.69, p = 0.401). The independent prognostic value of PNI was validated by multivariate analysis.ConclusionThis pilot investigation demonstrated that low prognostic nutritional index correlates with worse survival for patients with advanced NSCLC and taking EGFR-TKIs. The assessment of a convenient index, known as PNI, worth attention in routine clinical practice for patients following EGFR-TKIs treatment.

研究目的
本研究旨在探讨预后营养指数（prognostic nutritional index, PNI）——一项反映全身免疫营养状态的指标——对接受表皮生长因子受体酪氨酸激酶抑制剂（EGFR-TKIs）治疗患者的长期生存的预后价值。

研究方法
本研究为回顾性研究，纳入携带表皮生长因子受体（epidermal growth factor receptor, EGFR）敏感突变（19号外显子缺失或21号外显子L858R突变）的晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）患者，以探讨PNI与总生存期（overall survival, OS）的相关性。PNI计算公式为：10×血清白蛋白值（g/dl）+0.005×外周淋巴细胞计数（个/mm³）。采用单因素及多因素分析，鉴定PNI与其他临床病理因素的预后意义。

研究结果
最终共有144例患者符合纳入标准。用于生存分层的PNI最优截断值为48.78。与高PNI组（n=81）相比，低PNI组（n=63）患者的C反应蛋白（C-reactive protein, CRP）水平显著升高，且对TKIs治疗应答不佳。高PNI组患者的总生存期更优（风险比（hazard ratio, HR）=0.44，P=0.004），该优势在携带L858R突变的患者中尤为显著（HR=0.37，P=0.009），但在19号外显子缺失患者中未观察到统计学差异（HR=0.69，P=0.401）。多因素分析验证了PNI的独立预后价值。

研究结论
本先导性研究表明，低预后营养指数与接受EGFR-TKIs治疗的晚期NSCLC患者较差的生存结局显著相关。PNI作为一项便捷的评估指标，值得在接受EGFR-TKIs治疗患者的常规临床实践中予以关注。