Meta-Analysis
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2018; 24(15): 1658-1665
Published online Apr 21, 2018. doi: 10.3748/wjg.v24.i15.1658
Platelet-to-lymphocyte ratio in the setting of liver transplantation for hepatocellular cancer: A systematic review and meta-analysis
Quirino Lai, Fabio Melandro, Zoe Larghi Laureiro, Francesco Giovanardi, Stefano Ginanni Corradini, Flaminia Ferri, Redan Hassan, Massimo Rossi, Gianluca Mennini
Quirino Lai, Fabio Melandro, Zoe Larghi Laureiro, Francesco Giovanardi, Redan Hassan, Massimo Rossi, Gianluca Mennini, Hepato-bilio-pancreatic and Liver Transplant Unit, Department of Surgery, Sapienza University of Rome, Rome 00161, Italy
Stefano Ginanni Corradini, Flaminia Ferri, Division of Gastroenterology, Department of Clinical Medicine, Sapienza University of Rome, Rome 00161, Italy
Author contributions: Lai Q contributed to conception and design of the study; Lai Q, Melandro F, Giovanardi F, Ferri F and Hassan R contributed to acquisition of data; Lai Q and Melandro F analysed and interpreted the data; Lai Q drafted the article; Ginanni Corradini S, Rossi M and Mennini G critically revised the manuscript; and all authors approved the final version.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Quirino Lai, MD, PhD, Senior Lecturer, Hepato-bilio-pancreatic and Liver Transplant Unit, Department of Surgery, Sapienza University of Rome, Umberto I Policlinic of Rome, Viale del Policlinico 155, Rome 00161, Italy. lai.quirino@libero.it.
Telephone: +39-3493020126 Fax: +39-06499701
Received: March 9, 2018
Peer-review started: March 10, 2018
First decision: March 29, 2018
Revised: April 2, 2018
Accepted: April 9, 2018
Article in press: April 9, 2018
Published online: April 21, 2018
Processing time: 40 Days and 16.2 Hours
Abstract
AIM

To perform a systematic review and meta-analysis on platelet-to-lymphocyte ratio (PLR) as a risk factor for post-transplant hepatocellular cancer (HCC) recurrence.

METHODS

A systematic literature search was performed using PubMed. Participants of any age and sex, who underwent liver transplantation for HCC were considered following these criteria: (1) studies comparing pre-transplant low vs high PLR values; (2) studies reporting post-transplant recurrence rates; and (3) if more than one study was reported by the same institute, only the most recent was included. The primary outcome measure was set for HCC recurrence after transplantation.

RESULTS

A total of 5 articles, published between 2014 and 2017, fulfilled the selection criteria. As for the quality of the reported studies, all the investigated articles presented an overall high quality. A total of 899 cases were investigated: 718 cases (80.0%) were males. Three studies coming from European countries and one from Japan presented HCV as the main cause of cirrhosis. On the opposite, one Chinese study presented a greater incidence of HBV-related cirrhotic cases. In all the studies apart one, the PLR cut-off value of 150 was reported. At meta-analysis, high PLR value was associated with a significant increase in recurrence after transplantation (OR = 3.33; 95%CI: 1.78-6.25; P < 0.001). A moderate heterogeneity was observed among the identified studies according to the Higgins I2 statistic value.

CONCLUSION

Pre-transplant high PLR values are connected with an increased risk of post-operative recurrence of hepatocellular cancer. More studies are needed for better clarify the biological mechanisms of this results.

Keywords: Recurrence; Inflammation; Hepatocellular cancer; Liver transplantation; Platelet-to-lymphocyte ratio

Core tip: Poor data exist on the role of the inflammatory marker platelet-to-lymphocyte ratio (PLR) and hepatocellular cancer (HCC) recurrence after liver transplantation. This is the first systematic review and meta-analysis specifically investigating the role of PLR in the setting of liver transplant for HCC. Pre-transplant high PLR values confirmed their utility as predictors of recurrence, being connected with a 3.33-fold increased risk of post-transplant HCC recurrence.