Prevalence and characteristics of Epstein-Barr virus-associated gastric carcinomas in Tunisia

Objective Epstein–Barr virus (EBV) has been linked to
gastric carcinoma (GC) with worldwide geographical
variations of prevalence ranging from 1 to 18% of cases.
Investigations carried out in north Africa have shown that
some EBV-associated types of cancers are common in this
area. This study was taken to determine the prevalence of
EBV-associated GC in Tunisia.
Methods Ninety-six nonselected GC cases (male/female
ratio 1.7/1, mean age 60.9 years, range: 20–88 years) were
evaluated for the presence of EBV by polymerase chain
reaction as well as by in-situ hybridization for EBVencoded
small RNAs (EBERs) and immunohistochemistry
for LMP-1 and EBNA-2 expression.
Results EBV was detected by polymerase chain reaction
in 36% of cases, whereas EBERs were detected in the
tumor cells in only four cases (4.1%).
Immunohistochemistry for LMP-1 and EBNA-2 was
negative in all cases. The mean age for patients harboring
EBERs-positive GC was 55.7 years (range: 52–59 years).
All EBERs-positive GC cases were males of advanced
clinical stage (pT3–pT4). According to Lauren’s
classification, two cases were of diffuse histological type
and two cases were of intestinal type. In three cases, the
tumors have a proximal location and in the remaining case
the tumor arises in the antrum. All EBV strains detected
from EBV-associated GC were exclusively of type A and D,
prototype F, and XhoI-maintained variant.
Conclusion We conclude that the prevalence of
EBV-associated GC in Tunisia is low (4.1%), suggesting
that this virus is not an important etiological factor in GC
arising in north African populations. The clinicopathological
profile of EBV-associated GC in Tunisia did not differ
markedly from that found elsewhere.