The gastrointestinal tract (GIT) is the most common (30–40%) extranodal site involved in lymphoma. Although primary gastrointestinal lymphoma (PGIL) is a rare disease, comprising only 1–4% of gastrointestinal (GI) malignant tumors, its incidence is increasing. Different regions of the GIT are involved in different subtypes of PGIL with a various frequency that reflects the diversity of the causative agents and predisposing factors for each site and subtype of PGIL. Even though these malignant diseases are categorized under the common term of “lymphoma” they represent a heterogeneous group of malignant neoplasms which are different entities in terms of etiologic factors, predisposing conditions, pathogenesis, immunohistochemical profile, treatment strategy and prognosis. In this chapter the epidemiology of all subtypes of PGIL, factors and disorders contributing to the development of them, non-inherited and inherited conditions associated with a higher risk of them, diagnostic difficulties and pitfalls, and novel treatment strategies were comprehensively and concisely illuminated.
Part of the book: Lymphoma