Superiority of CRP-albumin-lymphocyte index (CALLY index) as a non-invasive prognostic biomarker after hepatectomy for hepatocellular carcinoma

Background: We aimed to investigate whether a novel biomarker incorporating albumin, lymphocytes, and CRP can predict the prognosis for hepatocellular carcinoma (HCC) after hepatectomy. Methods: Between January 2011 and December 2013, 384 patients who underwent hepatectomy in four university hospitals in Japan were investigated as a discovery cohort. The CRP-Albumin-Lymphocyte (CALLY index) was defined as (Albumin x Lymphocyte)/(CRP x 10(4)). Patients with a CALLY index >= 5 (n = 200) were compared to those with an index <5 (n = 184). Next, validation was performed using 267 patients from three other university hospitals (external validation cohort). Results: The number of TNM Stage III and IV patients was significantly higher in the CALLY <5 group than the >= 5 group (p = 0.003). There was a significant difference in the 5-year survival rate (CALLY >= 5: 71% vs. <5: 46%; p < 0.001). Multivariate analysis identified the CALLY index as an independent factor of overall survival. Similarly, there was a significant difference in the 5-year survival rate between the CALLY >= 5 (73%) and <5 (48%) groups (p < 0.001), and the CALLY index was identified as an independent prognostic factor in the external validation cohort. Conclusion: The CALLY index derived from CRP, albumin, and lymphocyte values is a promising predictive biomarker for postoperative prognosis of patients with HCC.