Follicular lymphoma is a mature B-cell lymphoma derived from germinal center B-cells and usually has a follicular appearance histologically. It is often characterized by genetic alteration t(14;18)(q32;q21) translocation.

Follicular lymphoma is one of the most common forms of non-Hodgkin lymphoma. Adults are most often affected (median age is sixth decade of life), and rates are highest in the United States and Western Europe.

There is a lack of consensus regarding risk factors for the development of follicular lymphoma.

Follicular lymphoma predominantly presents in the lymph nodes (most commonly peripheral lymph nodes) but can also involve the spleen, bone marrow, peripheral blood, or Waldeyer ring; however, extranodal presentations (ie, gastrointestinal tract, breast, soft tissue, testes, ocular adnexa) have been reported. Lymphadenopathy can wax and wane spontaneously. Usually, patients present with widespread disease but are asymptomatic.

Microscopically, the neoplastic cells are composed of varying proportions of centrocytes and centroblasts that proliferate in a nodular or follicular pattern. The relative proportions of these cells (along with other factors) determine the grading of follicular lymphoma.

Related topic: Cutaneous B-cell lymphoma