The Prognostic Impact of C-Reactive Protein-Albumin-Lymphocyte Index (Cally Index) in Patients with Surgically Resected Non-Small-Cell Lung Cancer.

Abstract

The C-reactive protein (CRP)-albumin-lymphocyte (CALLY) index is a new scoring system that evaluates both inflammatory and nutritional status. We aimed to investigate the clinical significance of the CALLY index as a prognostic biomarker in resected non-small-cell lung cancer (NSCLC). We classified 581 and 634 patients with NSCLC clinical stages I-IIIA who underwent surgery between 2013 and 2018 as the discovery and validation cohorts, respectively. The CALLY index was calculated using the following formula: (serum albumin × lymphocytes) / (CRP × 10⁴). The cutoff value of the CALLY index in the discovery cohort was determined using a time-dependent receiver operating characteristic curve analysis. Patients were classified into CALLY-high and CALLY-low groups, and associations between the CALLY index and clinicopathological factors and prognosis was evaluated. In the discovery cohort, 329 (56.6%) and 252 (43.3%) patients were classified as CALLY-high and CALLY-low, respectively; in the validation cohort, 353 (55.7%) and 281 (44.3%) patients were classified as CALLY-high and CALLY-low, respectively. In both cohorts, the CALLY-low group was associated with older age, male sex, smoking, and advanced cancer stage. Multivariable analysis in both cohorts showed that CALLY-low was an independent poor prognostic factor for recurrence-free survival: hazard ratio (HR) 1.4; 95% confidence interval (CI) 1.02-2.02 and HR 1.4; 95% CI 1.02-1.87, respectively. It was also an independent poor prognostic factor for overall survival: HR 2.1; 95% CI 1.31-3.25 and HR 1.6; 95% CI 1.11-2.29, respectively. The CALLY index is a useful prognostic predictor in resected NSCLC.