disease arises from structure mature B cell B-cell neoplasm neoplasm of mature B-cells 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). DOID:706 EFO:0000096 Editor note: is a non-hodgkin in ONCOTREE ICD9:202.0 MONDO:0004949 NCIT:C27910 ONCOTREE:MBN SCTID:269476000 UMLS:C1334633 mature B-cell lymphocytic neoplasm mature B-cell neoplasm mature B-cell neoplasms neoplasm (disease)