Follicular Lymphoma

**Semantic type:** Neoplastic Process

**Definition:** A neoplasm of follicle centre B cells which has at least a partial follicular pattern. Follicular lymphomas comprise about 35% of adult non-Hodgkin lymphomas in the U.S. and 22% worldwide. Most patients have widespread disease at diagnosis. Morphologically, follicular lymphomas are classified as Grade 1, Grade 2, and Grade 3, depending on the percentage of the large lymphocytes present. The vast majority of cases (70-95%) express the BCL-2 rearrangement [t(14;18)]. Histological grade correlates with prognosis. Grades 1 and 2 follicular lymphomas are indolent and grade 3 is more aggressive (adapted from WHO, 2001).

**Synonyms:** - Follicle Center Lymphoma - Follicle Center Lymphoma - Follicular Centre Cell Lymphoma - Follicular Non-Hodgkin Lymphoma - Follicular Non-Hodgkin Lymphoma - Follicular Non-Hodgkin's Lymphoma - Follicular Non-Hodgkin's Lymphoma - Follicular lymphoma - Follicular lymphoma, unspecified, unspecified site - LYMPHOMA, FOLLICULAR, MALIGNANT - Lymphoma, Follicular Centre Cell - follicular lymphoma