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 EBV-encoded 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.


CONCLUSIONS
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.
Trimeche
Mounir
M
Department of Pathology, Farhat Hached Hospital, Sousse 4000, Tunisia. m_trimech@yahoo.fr
Ksiâa
Feriel
F
Ziadi
Sonia
S
Mestiri
Sarra
S
Hachana
Mohamed
M
Gacem
Riadh Ben
RB
Sriha
Badreddine
B
Korbi
Sadok
S
D000230:Adenocarcinoma / Q000453:epidemiology / Q000473:pathology* / Q000821:virology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020031:Epstein-Barr Virus Infections / Q000150:complications / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000821:virology; D014416:Tunisia / Q000453:epidemiology; D055815:Young Adult
D012367:RNA, Viral