Seyed Amir Banikarim
1 
, Sajad Ataei Azimi
2 , Ahmadreza Maghsoudi
3 , Zahed Karimi
4 , Fatemeh Rostami
5 , Afrooz Kargaran Dehkordi
6 , Shirin Shamsghahfarokhi
7 , Leila Ashrafi
8 , Naeem Nikpour
9* 1 Hematology-Oncology Department, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
2 Hematology-Oncology Department, Mashhad University of Medical Sciences, Mashhad, Iran
3 Department of Internal Medicine, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
4 Department of Internal Medicine, School of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
5 Operating Room Department, School of Allied Medical Science, Fasa University of Medical Sciences, Fasa, Iran
6 Department of Pulmonary Diseases, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
7 Department of Internal Medicine, School of Medicine, Hajar Hospital, Shahrekord University of Medical Sciences, Shahrekord, Iran
8 Department of Internal Medicine, Clinical Research Development Unit, Hajar Hospital, Shahrekord University of Medical Sciences, Shahrekord, Iran
9 Department of Hematology and Medical Oncology, Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran
Abstract
Introduction: Serum gamma-glutamyl transferase (GGT) elevation is a reliable marker for various chronic diseases, including cancer. Therefore, in this study, we investigated the association between increased serum GGT levels and the risk of lung cancer, employing a systematic review and meta-analysis approach.
Materials and Methods: To identify relevant articles up to 28 February 2026, the databases Web of Science, Cochrane, Scopus, PubMed, and Embase were searched, along with the Google Scholar search engine. The search strategy was applied without any restrictions on language or publication date. All statistical analyses were ultimately conducted using STATA software, version 14.
Results: In this meta-analysis, six observational studies were included, and the pooled findings indicated that elevated serum GGT levels were directly associated with an increased risk of lung cancer (HR: 1.11; 95% CI: 1.06–1.16). Furthermore, subgroup analyses showed that higher serum GGT levels were linked to a greater risk of lung cancer in studies conducted in Korea (HR: 1.10; 95% CI: 1.05–1.16), the United Kingdom (HR: 1.19; 95% CI: 1.03–1.37), cohort studies (HR: 1.12; 95% CI: 1.07–1.17), and among men (HR: 1.20; 95% CI: 1.13–1.27).
Conclusion: Elevated serum GGT levels increased the overall risk of lung cancer by 11% and, specifically, by 20% in men, whereas this association was not statistically significant in women.
Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO (ID: CRD420261376343) and Research Registry (UIN: reviewregistry2103) websites.