Analysis of Epstein Barr Virus Encoded RNA Expression in Nasopharyngeal Carcinoma in North-Eastern India: A Chromogenic in Situ Hybridization Based Study.
BACKGROUND
Nasopharyngeal carcinoma (NPC) is a common cancer in the North-East region of India. Though the role of environmental contributors of NPC in the North-Eastern part of India is firmly established, EBV as an etiological agent in the region remains unexplored.


METHODS
Fifty-one patients, who presented at the department of ENT, NEIGRIHMS and were confirmed as NPC upon histopathological examination, were included in the study. Chromogenic in-situ hybridization (CISH) was used for the evaluation of EBER (Epstein Barr Virus Encoded RNA). Presence of nuclear signals was taken as positive for EBER expression. EBER status was correlated with various clinicopathological parameters like age, sex, dietary habits, histological types of NPC, and ethnicity of the patients.


RESULTS
The age range of the study group was 25 to 70 years with a mean age of 44.64 years and a male:female ratio of 3:2. Non-keratinizing undifferentiated type of NPC was the most common histological type. EBV was positive in 59% (30/51) of our cases. It showed a statistically significant correlation with the Naga community (P=0.01), with consumption of smoked food (P=0.02), and cigarette smoking (P=0.02). There was no correlation of EBV with age, sex, lymph node metastasis, stage, and histology.


CONCLUSIONS
Our result indicates that EBV may be an additional risk factor in the pathogenesis of NPC in this region of India. So apart from lifestyle modification, a future study for a screening test for EBV viral load even in asymptomatic patients may be considered, for determination of disease susceptibility, early diagnosis, and proper management.
Department of Pathology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
Anjan
A
Saikia
Department of Pathology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India.
Vandana
V
Raphael
Department of Otorhinolaryngology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India.
N-Brian
NB
Shunyu
Department of Pathology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India.
Yookarin
Y
Khonglah
Department of Pathology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India.
Jaya
J
Mishra
Department of Pathology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India.
Ankit-Kumar
AK
Jitani
Department of Otorhinolaryngology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, India.
Jayanta
J
Medhi
EBER; EBV; ISH; Nasopharyngeal cancer; Nasopharynx