[Detection of HTLV-1 genome in primary gastrointestinal lymphomas: A study on 22 years [1981- 2003] pathology archive biopsy specimens in Imam Reza Hospital, Mashhad, Iran]

ABSTRACT

Non-Hodgkin's lymphoma [NHL] with primary gastrointestinal localization [GI-NHL] represents only 1-4% of the malignant tumors in the gastrointestinal tract. However, the gastrointestinal tract is the most common extra nodal site of NHL. The etiology of GI-NHL remains unknown, however, recent studies have shown that infection with viruses like HTLV-I in the gastrointestinal tract may increase the risk of T cell NHL. The present study was designed to investigate the presence of HTLV-1 genome using PCR on paraffin embedded tissue of primary GI-NHL specimens diagnosed during the period from 1981 to 2003 in the Department of Pathology, Imam Reza Hospital, Mashhad, Iran. The total number of biopsies was 103, 573; and 65 cases with primary GI-NHL were found. All these 65 specimens were stained with Immunohistochemical markers such as LCA, CD20 and CD3. The presence of HTLV-1 genome was detected in 48 selected patients using tax, LTR, pol and eny [GD21] primers. Our results show that male to female distribution was 1.5 1. Most of the patients were in their second of third decades of life. Eight patients [12.3%] had primary lymphoma in the stomach, 52 [80%] in the small intestine, two [3%] in the large intestine, and three [4.7%] patients had multifocal involvements [Ileocecal]. According to the Revised European-American Lymphoma [REAL] classification, IPSID Lymphoma was the most frequent histologic subtype, comprising 40% of the cases. Sixty-four cases were classified as B cell lymphomas, and one as T-cell lymphoma. Out of 48 specimens which were amplified using PCR, two [4.2%] were positive for HTLV-1. The first case was a 55-year old male with diffuse pleomorphic T cell lymphoma who had a lesion in stomach; and the second case was a 15-month-old female with IPSID lymphoma who had involvement at duodenum