Systematic Reviews
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Oncol. Oct 24, 2022; 13(10): 822-834
Published online Oct 24, 2022. doi: 10.5306/wjco.v13.i10.822
Neutrophil-to-lymphocyte ratio as a prognostic factor for survival in patients with colorectal liver metastases: A systematic review
Menelaos Papakonstantinou, Stylianos Fiflis, Gregory Christodoulidis, Mariano Cesare Giglio, Eleni Louri, Savvas Mavromatidis, Dimitrios Giakoustidis, Vasileios N Papadopoulos, Alexandros Giakoustidis
Menelaos Papakonstantinou, Stylianos Fiflis, Eleni Louri, Savvas Mavromatidis, Dimitrios Giakoustidis, Vasileios N Papadopoulos, Alexandros Giakoustidis, Department of Surgery, General Hospital Papageorgiou, Aristotle University of Thessaloniki, Thessaloniki 56429, Greece
Gregory Christodoulidis, Department of General Surgery, University Hospital of Larissa, Larissa 41110, Greece
Mariano Cesare Giglio, Department of Clinical Medicine and Surgery, Federico II University of Naples, Naples 80138, Italy
Author contributions: Papakonstantinou M and Fiflis S contributed equally to this work and wrote most of the manuscript; Papakonstantinou M, Fiflis S and Giakoustidis A designed the research study, performed the research and analyzed the data; Christodoulidis G offered guidance and assisted as a corresponding author; Giglio M offered guidance and performed manuscript revisions; Louri E and Mavromatidis S assisted in writing part of the introduction and performed manuscript revisions; Giakoustidis D and Papadopoulos VN assisted in writing part of the discussion and performed manuscript revisions; Giakoustidis A perceived the idea and assisted as a supervising author; all authors have read and approved the final manuscript.
Conflict-of-interest statement: All authors report no relevant conflict of interest for this article.
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 that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Gregory Christodoulidis, MD, PhD, Consultant Physician-Scientist, Department of General Surgery, University Hospital of Larissa, Mezourlo, Larissa 41110, Greece. gregsurg@yahoo.gr
Received: April 26, 2022
Peer-review started: April 26, 2022
First decision: June 22, 2022
Revised: July 8, 2022
Accepted: October 11, 2022
Article in press: October 11, 2022
Published online: October 24, 2022
Abstract
BACKGROUND

The inflammatory response to tumor has been proven to be closely related to the prognosis of colorectal cancer. Neutrophil to lymphocyte ratio (NLR) is a widely available inflammatory biomarker that may have prognostic value for patients with colorectal liver metastasis (CRLM).

AIM

To assess the role of NLR as a prognostic factor of survival and tumor recurrence in patients with CRLM.

METHODS

A systematic literature search of PubMed, Cochrane Library and clinicaltrials.gov was conducted by two independent researchers in order to minimize potential errors and bias. Conflicts were discussed and settled between three researchers. Studies including patients undergoing different types of medical interventions for the treatment of CRLM and evaluating the correlation between pretreatment NLR and disease-free survival (DFS) and overall survival (OS) were included in the review. Nineteen studies, involving 3283 patients matched our inclusion criteria.

RESULTS

In the studies included, NLR was measured before the intervention and the NLR thresholds ranged between 1.9 and 7.26. Most studies used 5 as the cut-off value. Liver metastases were treated with hepatectomy with or without chemotherapy regimens in 13 studies and with radiofrequency ablation, radioembolization, chemoembolization or solely with chemotherapy in 6 studies. High NLR was associated with decreased OS and DFS after liver resection or other medical intervention. Moreover, high NLR was associated with poor chemosensitivity. On the contrary, CRLM patients with low pretreatment NLR demonstrated improved OS and DFS. NLR could potentially be used as a predictive factor of survival and tumor recurrence in patients with CRLM treated with interventions of any modality, including surgery, chemotherapy and ablative techniques.

CONCLUSION

NLR is an inflammatory biomarker that demonstrates considerable prognostic value. Elevated pretreatment NLR is associated with poor OS and DFS in patients with CRLM who are submitted to different treatments.

Keywords: Neutrophil-to-lymphocyte ratio, Colorectal liver metastasis, Prognosis, Survival

Core Tip: Colorectal cancer is the third most common cancer globally and liver is the most common site of metastasis. Even though surgery and chemotherapy are the main treatment options, prognostic markers are also essential for the progress and future management of the disease. Neutrophil-to-lymphocyte ratio (NLR) is a promising biomarker that has been recently proposed as an indicator for the survival and recurrence of various malignancies. In our review we assess the role of NLR in the overall survival of patients with colorectal liver metastases.