Abstract 4782: Detection of EBV nucleic acid and expression of oncogenic protein LMP-1 in Reed-Sternberg cells of Hodgkin's lymphoma.

Abstract

Epstein-Barr virus (EBV) is the causative agent of infectious mononucleosis and is implicated in the development of several human malignancies, such as nasopharyngeal carcinoma (NPC) and Hodgkin's Lymphoma (HL). While the incidence of Hodgkin's Lymphoma in Iraq is not yet investigated, according to the WHO Hodgkin's Lymphoma is one of the 10 most frequent types of cancer in Iraq (http://www.who.int/disasters/repo/10062.pdf). The present study aimed to determine the association between HL and EBV in middle Euphrates region of Iraq, and to determine whether it is related to certain age group or specific histologic subtypes. It also aims to compare the pattern with other developing or developed countries. This retrospective study includes 86 formalin-fixed paraffin-embedded tissue blocks from HL patients, these were compared with 35 patients with Reactive Follicular Hyperplasia, that were age and gender matched. All the samples belonged to the period between Jan.2008 to April2010. The presence of EBV DNA was investigated by polymerase chain reaction (PCR), while the expression of the oncogenic protein (LMP-1) in Reed-Sternberg cells by immunohistochemistry (IHC). The mean age group of HL patients was 28.5 old years with a median of 25 years old. There were 49 males and 37 females. Age group of 16-45 years was the largest one and represented 66.2%. The third decade took the peak incidence (26/86, 30.2%). patients aged less than 16 years were 17.5%, while 16.3% of patients were more than 45 years old. Mixed cellularity HL was the most common subtype represented 47.6% of all the cases, followed by nodular sclerosis (33.7%) while the lymphocyte-rich, and lymphocyte depleted subtypes were (8.1%, 7%) respectively, whereas Lymphocyte Predominant was seen in 3.48% of cases. EBV DNA was detected in 39.5% of the cases, while the expression of LMP-1 in Reed Sternberg cells was found in 85.3% of the EBV-positive HL. The highest rate of EBV was seen in the children age group (less than 16 years; 53.3%), while the lowest rate was among young adults (16-45 years; 35.08%). Older age group (more than 45 years) has a rate of EBV presented (39.5%) which was higher than the young adult patients, but lower than the children age group. Histologically, the most frequent viral association was observed in mixed cellularity subtype (56.1%), followed by lymphocyte-rich and lymphocyte depleted subtypes (42.9%, 33.3%) respectively. The least frequency of association was in nodular sclerosis type (20.7%), while lymphocyte predominant subtype showed negative relationship with EBV-positive HL. EBV positive cases were mostly males (40.81%) compared to females (37.8%). Citation Format: Dhiya S. Al-Shumary, Karrar A.A. Ali Beg, Alae A. Yaseen, Salman A. Al-Jibouri, Kaswer M. Al-Toriahi. Detection of EBV nucleic acid and expression of oncogenic protein LMP-1 in Reed-Sternberg cells of Hodgkin's lymphoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4782. doi:10.1158/1538-7445.AM2013-4782 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.