| The mucosa-associated lymphoid tissue lymphoma of the ocular adnexal (MALT lymphoma) is one of the most common malignant tumors located at the ocular adnexal. It represents a distinct subgroup of B-cell non-Hodgkin Lymphomas (NHL) arising from extranodal sites. The neoplasm usuall}' arises from the gastrointestinal tract, but also can be found at ocular adnexal. It is characterized by an indolent clinical behavior, tend to remain localized to the sites for long periods and to have a better prognosis. Ocular adnexal MALT lymphoma may involve the eyelids, conjunctiva, orbital connective tissue, or lacrimal structures, the MALT lymphoma we mention here including these four kinds above. In 1 983, Isaacson and Wright put forward the concept of mucosa-associated lymphoid tissue lymphoma. And in 1994, the new revised European American lymphoma classification (REAL) of lymphoid malignancy first proposed by the International Lymphoma Study Group differs from older classification in recognizing these new entities and is not only based on classic histological criteria but also clinical, immunohistochemical and molecular genetic data. Though there is lack of mucosal tissue at ocular adnexal, MALT lymphoma of ocular adnexal have typical clinical and histological changes. MALT lymphomas are thought to have an indolent natural history and respond well to local resection and radiotherapy.But the pathogenesis of MALT lymphoma is still unknown, the study group are investigating from molecular biology aspect. Recently, immunoglobulin heavy chain of MALT lymphoma have been found that 75% have genetic recombination, and lack of genetic recombination of Bcl-2 and C-myc. Cytogenetics also show that MALT lymphoma have several kinds of anomaly of chromosome such as trisomy.Immunohistochemistry stains used included CD20 (to identify B lymphocytes) and immunoglobulin A light chain are both positive, all of the neoplasm are malignant lymphoma.Recently, a novel fusion gene : API2-MALT1 become international hot spot, apoptosis inhibitor gene-API2 (or C-IAP2, HI API, MIHC) and a novel gene MALT1. In 1999, Dierlamm and colleagues showed that the t(l 1;18) produced a fusion of API2 on chromosome Ilq21 with MLT (for MALT lymphoma-associated translocation) on chromosome 18q21, now known as MALT1. The other groups show that 50% of low-grade malignant MALT lymphoma have translocation, the t(ll;18)(q21;q21) represents the most structural abnormality in MALT lymphoma. It was hypothesized that the t(ll;18) , owing to the absence of the API2 gene, conferred a survival advantage to MALT lymphomas and allowed for antigen-independent proliferation. The discovery of MALT1 gene brings a new subject to MALT lymphoma. Until very recently, the function of the MALTI gene and protein was unknown. Most of the research was focus on gastrointestinal MALT lymphoma, there are few article about lymphoma at ocular adnexal. For this point of view, we design a series steps of experiments, collecting the tissue surgically removed, using the RT-PCR methods in order ro reveal partly of molecular genetics mechanism. We try to figure out how the MALT lymphoma at ocular adnexal occurs, aad its influence to disease's development and prognosis. The focal point of our experiment is to find the relation between the API2 and MALTI gene variation and MALT lymphoma processes. The contents and results are as follows:1. Clinical Case CollectionOur experiment study of ocular adnexal lymphoma base on the department of ophthalmology located in CHANGZHEN hospital over years period was undertaken. 35 cases 40 eyes, including 19 cases (22 eyes) male and 16 cases (18 eyes) female, the ratio is 1.19:1. and with a mean age of 61.7 (range 24~88) years. All of the 35 patients have B-ultrasound and computed tomography (CT) scan and/or magnetic resonance imaging (MRI) examination. The tissue surgically removed have been routinely prepared slides of tissues fixed in 10% formalin and embedded in paraffin wax,hematoxylin and eosin Staining. Disease is defined as MALT lymphoma by p...
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