Reduction in Non-Protein Respiratory Quotient Is Related to Overall Survival after Hepatocellular Carcinoma Treatment

BACKGROUND: Transcatheter arterial chemoembolization (TACE) is an effective treatment for hepatocellular carcinoma (HCC) that can occasionally lead to the shortening of life expectancy. We aimed to make a new and more accurate prognostic model taking into account the course of disease after TACE. METHODOLOGY/PRINCIPAL FINDINGS: We performed a prospective cohort study involving 100 HCC patients who underwent TACE at Kobe University Hospital. Indirect calorimetry and blood biochemical examinations were performed before and 7 days after TACE. Time-dependent and time-fixed factors associated with 1-year mortality after TACE were assessed by multivariate analyses. A predictive model of 1-year mortality was established by the combination of odds ratios of these factors. Multivariate analyses showed that the ratio of non-protein respiratory quotient (npRQ) (7 days after/before TACE) and Cancer of Liver Italian Program (CLIP) score were independent factors of 1-year mortality after TACE (p = 0.014 and 0.013, respectively). Patient-specific 1-year mortality risk scores can be calculated by summarizing the individual risk scores and looking up the patient-specific risk on the graph. CONCLUSIONS: The short-term reduction of npRQ was a time-dependent prognostic factor associated with overall survival in HCC patients undergoing TACE. CLIP score was a time-fixed prognostic factor associated with overall survival. Using the prediction model, which consists of the combination of time-dependent (npRQ ratio) and time-fixed (CLIP score) prognostic factors, 1-year mortality risk after TACE would be better estimated by taking into account changes during the course of disease.