Epstein-Barr virus (EBV)-associated gastric cancer has been proposed to be a distinct gastric cancer molecular subtype. The prognostic significance of EBV infection in gastric cancer remains unclear and needs further investigation. Our study aimed to analyze EBV-positive and EBV-negative gastric cancer patients regarding their personal and tumor-related characteristics, and compare their overall survival.
Gastric cancer patients consecutively treated at the Riga East University Hospital during 2009–2016 were identified retrospectively. Tumor EBV status was determined by in-situ hybridization for EBV-encoded RNA (EBER). Information about clinicopathological characteristics was obtained from patient questionnaires, hospital records. Overall survival was ascertained through 30 July 2017. Cox proportional hazard regression models adjusted for personal and tumor-related covariates compared survival between EBV-positive and EBV-negative patients.
There were a total of 302 gastric cancer patients (61% males) with mean and SD age 63.6 ± 11.5 years. EBER positivity was present in 8.6% of tumors. EBV-positive gastric cancer patients had better survival at 80 months [adjusted hazard ratio = 0.37, 95% confidence interval (CI) = 0.19–0.72] compared to EBV-negative patients. Worse survival was observed for patients with stage III (hazard ratio = 2.76, 95% CI = 1.67–4.56) and stage IV (hazard ratio = 10.02, 95% CI = 5.72–17.57) compared to stage I gastric cancer, and overlapping and unspecified subsite (hazard ratio = 1.85; 95% CI = 1.14; 3.00) compared to distal tumors.
Tumor EBV positivity is a favorable prognostic factor in gastric cancer.
aInstitute of Clinical and Preventive Medicine
bFaculty of Medicine, University of Latvia
cRiga East University Hospital
dAcademic Histology Laboratory, Riga, Latvia
eDivision of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland, USA
fDepartment of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
gInstitute of Information Technology, Riga Technical University, Riga, Latvia
hDepartment of Pathology and Laboratory Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
iThe Centre of Disease Prevention and Control of Latvia, Riga, Latvia
Received 7 January 2019 Accepted 7 June 2019
Correspondence to Evita Gasenko, Faculty of Medicine, Institute of Clinical and Preventive Medicine, University of Latvia and Riga East University Hospital, Oncology Centre of Latvia, 4 Hipokrata Street, LV 1079 Riga, Latvia, Tel: +371 67040917; fax: +371 67536160; e-mail: firstname.lastname@example.org