Significance of NLDA, the commixed index of inflammation, immune responses, hemostasis, and nutrition, for predicting metastatic non-small cell lung cancer prognosis and metastases

PURPOSE This study aimed to take a comprehensive review of the hematological indexes and discover a novel, comprehensive, and economical index for prognostic prediction. RESULTS The predictive prognostic model revealed that an elevated value of NLDA (NLDA = neutrophil count/lymphocyte count × D-dimer count/albumin) was an independent risk factor for one-year adverse prognosis (hazard ratio = 3.038; 95% confidence interval [CI], 1.959-4.712; P < 0.001). The C-indexes of internal and external validation in nomogram were 0.738 (95% CI, 0.686-0.79) and 0.731 (95% CI, 0.631-0.831), respectively. The areas under the curves of the NLDA values in retrospective and prospective studies were 0.700 (95% CI, 0.631-0.769; P < 0.001) and 0.692 (95% CI, 0.535-0.822; P = 0.005), respectively. The cut-off value of NLDA was 0.15. NLDA was positively associated with M stage (P = 0.032), organ metastasis counts (P = 0.006), liver metastases (P = 0.019), and vertebrae metastases (P = 0.013). MATERIALS AND METHODS This was a retrospective and prospective study. The clinicopathological characteristics and hematological parameters of stage IV non-small cell lung cancer patients were analyzed retrospectively and prospectively to establish a valid predictive prognostic model. The primary endpoint was the 1-year overall survival. The predictive prognostic model was established and validated by Cox Regression and nomogram. The cut-off and predictive prognostic values of the novel indexes were calculated through the receiver operating characteristic curves. The chi-square test was used to explore the correlation between the new prognostic hematological index and metastatic characteristics. CONCLUSIONS In this study, NLDA, a new, comprehensive and economic parameter, was found to be an independent adverse prognostic factor for stage IV non-small cell lung cancer patients, and was positively associated with organ metastases.