*Javed Fayyaz Wazir; **Fatima Shehab, **Urmil Prabha Brahmi
* Department of Pathology. The Royal College of Surgeons in Ireland. Bahrain.
** Department of Pathology, Arabian Gulf University, Kingdom of Bahrain.
Objectives. To determine the association of Epstein-Barr Virus in gastric tumours in the Kingdom of Bahrain and to explore its role in tumour pathogenesis.
Method. A reterospective study was performed including 58 cases of gastric tumours between January 2001 till December 2005 received in Histopathology department Salmaniya Medical Complex, Kingdom of Bahrain. These cases consist of carcinomas, carcinoids and lymphomas. Formalin fixed tissue sections were used to perform immunohistochemistry and In- Situ Hybridization using Anti-EBV-LMP (Latent Membrane Protein) antibodies and EBER PNA probe respectively.
Results.- The EBV-RNA expression was detected in 44.40% of the intestinal type adenocarcinomas, 25% signet ring cell type adenocarcinomas, 100% carcinoid tumours and 50% lymphomas (p value < 0.036). Tumours showing positive staining pattern for EBER PNA probe were also positive for EBV-LMP except the carcinoid tumours. Of the EBV positive carcinoma cases 75% were poorly differentiated tumours. Conclusion.-This study is first in the kingdom of Bahrain showing EBV association in gastric tumours. The presence of EBV infection in carcinoma, carcinoid and lymphoma cells, and its absence in normal or metaplastic gastric epithelium suggests that EBV infection is a terminal event rather than an initiating factor in tumour pathogenesis. More prospective studies are required to clarify the epidemiology and aetiology of EBV-associated gastric cancer in the Arabian Gulf region. Key words. Gastric tumours, Epstein Barr Virus Association.