Letter to the Editor: Impact of Ageing on Hepatic Malignancy Resection: Is Age Really a Risk Factor for Mortality?

Abstract

Dear Editor, I read with great interest the recent article titled ‘‘Impact of Ageing on Hepatic Malignancy Resection: Is Age Really a Risk Factor for Mortality?’’ published by Liu et al.[1]. This study reported the effect of ageing on outcomes after hepatectomy in 357 patients. The authors found that age was not associated with poorer mortality outcomes in the univariate and bivariate analysis. I concur with the authors that with an ageing population, studying the impact of ageing on outcomes after liver resection will be paramount for many surgical centres around the world. However, I have concerns about the design of this study. In this study, while the authors accounted for comorbidities, variables associated with ageing such as frailty, sarcopenia, and malnutrition were not included. These variables have been shown to have an impact on outcomes after liver resection [2]. Also, the authors reported that the majority of the cases were metastatic colorectal adenocarcinoma (75.9%), followed by primary hepatocellular carcinoma (13.2%). However, the distribution of the diagnosis according to the age groups was not presented. This is important for the readers as the outcomes after hepatic resection in primary and secondary hepatic malignancies have shown to differ greatly [3, 4]. In this study, the authors decided to account for confounders as such age, American Society of Anaesthesiologists (ASA C 3), complex resection, ICU admission and stay, length of hospital stay, morbidity, Clavien-Dindo C 3, and categories of complication. However, their justification for the decision to include the above confounders was not presented. At the same time, important intra-operative variables such as blood loss, type of hepatic malignancy and major resections were not included in the bivariate model [5]. In addition, the authors also did not elaborate on the reason for choosing a bivariate binary logistic regression model. The authors chose to analyse age as a continuous variable to make their data more applicable to real-life scenarios. They could have gone further to use a multivariate model which is more reflective of real-life experience where multiple confounders are at play instead of accounting for individual confounders in the bivariate binary model. Finally, the authors attributed the excellent outcomes to the careful patient selection process. Throughout the study, the patient selection framework was not presented. Readers may benefit greatly if the authors elaborate on their patient selection process so that the framework may be adopted by other surgical centres. In conclusion, I hope that the authors can clarify the comments mentioned above so that readers can better evaluate the impact of ageing on hepatic malignancy resection for the safety of liver resection in the elderly population to be determined.