NCIt definition : A clinico-pathological entity reflecting the multiple polyps throughout the gastrointestinal
tract created as a result of involvement by a non-Hodgkin lymphoma. Typically, mantle
cell lymphomas involving the gastrointestinal tract give rise to multifocal lymphomatous
polyposis. Importantly, other histologic subtypes of non-Hodgkin lymphoma can also
produce this clinico-pathological entity. (WHO, 2000);