Follicular lymphoma (FL) is a common, generally slow-growing B-cell non-Hodgkin lymphoma driven frequently by the BCL2 t(14;18) translocation. Typical presentation is painless lymphadenopathy; diagnosis requires excisional biopsy and immunophenotyping. Many patients with low tumor burden can be managed with observation; localized radiotherapy can control early stages. Symptomatic or advanced disease is treated with anti-CD20-based chemoimmunotherapy (e.g., rituximab combinations) or newer targeted agents. Emerging immunotherapies, including CAR-T and bispecific antibodies, have expanded options for relapsed/refractory disease .
What is follicular lymphoma?
Follicular lymphoma (FL) is an indolent B-cell non-Hodgkin lymphoma that arises from germinal-center B cells. It often has a follicular (nodular) growth pattern on biopsy and commonly expresses BCL2 due to the t(14;18) translocation.
Who gets it?
FL most commonly presents in adulthood; the typical age at diagnosis is around 60 years. It is one of the more common subtypes of non-Hodgkin lymphoma, accounting for roughly one in five cases. It does not spread by contact and is not infectious.
How it behaves and where it appears
Many patients have widespread lymph node involvement at diagnosis because FL cells can circulate. Bone marrow involvement is common. The disease is usually slow growing (indolent), but a minority of cases transform into a more aggressive lymphoma.
Symptoms and diagnosis
The most frequent initial sign is painless swelling of lymph nodes in the neck, armpit, or groin. Some people have systemic "B symptoms" such as unexplained fever, night sweats, tiredness, or weight loss. Diagnosis requires an excisional lymph-node biopsy with histology and immunophenotyping (CD20+, often CD10+, BCL2 expression). Staging typically uses the Ann Arbor system supplemented by PET-CT and bone-marrow biopsy when needed.
Prognosis and risk assessment
Prognosis varies. Clinical tools such as the FLIPI (Follicular Lymphoma International Prognostic Index) estimate risk by combining clinical features. Many patients live many years with disease control. Management decisions are individualized by symptoms, stage, comorbidities, and patient preference.
Treatment today
Observation (watchful waiting) remains appropriate for asymptomatic patients with low tumor burden. For early-stage (I-II) disease, involved-site radiotherapy can be curative in some cases.
Advanced or symptomatic disease is treated systemically. Standard options include anti-CD20 monoclonal antibody therapy (rituximab) alone or combined with chemotherapy (examples historically include CHOP or CVP). Bendamustine plus rituximab is frequently used for first-line systemic therapy in many centers.
For relapsed or refractory disease, several targeted and immunologic options have expanded the arsenal: oral agents targeting PI3K pathways, the EZH2 inhibitor tazemetostat for selected patients, and cellular or bispecific T-cell-engaging immunotherapies that have shown strong activity in heavily pretreated patients. These newer modalities are reshaping management of relapsed FL but have specific toxicity profiles and access considerations .
Bottom line
Follicular lymphoma is a common, usually slow-growing B-cell lymphoma with wide variability in course. Many patients can be observed for long periods; others require radiotherapy or systemic therapy. Advances in targeted agents and immunotherapies are providing more options for relapsed disease, and treatment should be individualized with input from lymphoma specialists.
- Confirm current approvals, indications, and dates for CAR-T therapies in follicular lymphoma (which products and FDA/EMA indications).
- Confirm current approval status and recommended indications for bispecific antibodies (e.g., mosunetuzumab, epcoritamab) in FL.
- Verify current PI3K inhibitor approvals and safety restrictions for FL.
- Confirm tazemetostat approved indications for FL (EZH2-mutant vs. wild-type) and any label updates.