Follicular lymphoma (FL) is the most common of non-Hodgkin's lymphomas accounting for approximately 20 percent to 30 percent of all non-Hodgkin's lymphoma. It is defined as a lymphoma of follicle center B-cells (centrocytes and centroblasts), which has at least a partially follicular pattern. It is positive for the B-cell markers CD10, CD19, CD22, and usually CD20, but almost always negative for CD5. It is called 'follicular' lymphoma because the abnormal lymphocytes often collect in lymph nodes in clumps that are known as 'follicles'.
Common signs of disease include enlargement of the lymph nodes in the neck, underarm, stomach, or groin, as well as fatigue, shortness of breath, night sweats, and weight loss. Often, people with FL have no obvious symptoms of the disease at diagnosis.
Over time, some patients with FL may eventually develop a transformed lymphoma, which is often more aggressive and usually requires more intensive types of treatment.
The first sign of the condition is often a painless swelling in the neck, armpit or groin, caused by enlarged lymph nodes. Sometimes more than one group of nodes are affected. The lymphoma may spread to involve various organs in the body, such as the bone marrow, liver, lungs or skin. Some people experience a loss of appetite and tiredness.
Other symptoms you may have include, which are known as B-symptoms.
- Loss of appetite and weight loss
- Drenching sweats, especially at night
- Tiredness or fatigue
- Widespread itching, without any skin problems
- Being more prone to infections
- Unexplained high temperatures
When follicular lymphoma occurs in parts of the body outside of your lymph nodes (extranodal sites), other symptoms are possible. These may include shortness of breath or abdominal pain.
If the lymphoma occurs in the bone marrow, it can cause low blood cell counts. This can result in:
- Anaemia, causing marked tiredness and shortness of breath
- Low platelets, making you prone to bruise easily or bleed.
Other symptoms may include night sweats, unexplained high temperatures, and weight loss. These are known as B symptoms.
A translocation between chromosome 14 and 18 results in the overexpression of the bcl-2 gene.As the bcl-2 protein is normally involved in preventing apoptosis, cells with an overexpression of this protein are basically immortal. The bcl-2 gene is normally found on chromosome 18, and the translocation moves the gene near to the site of the immunoglobulin heavy chain enhancer element on chromosome 14. Translocations of BCL6 at 3q27 can also be involved.
There's no known way to prevent FL. However, it may be possible to reduce your risk for the disease by avoiding known risk factors such as obesity and HIV.
A diagnosis is made by removing an enlarged lymph node, or part of it, and examining the cells under a microscope (biopsy). It is a very small operation and may be done under local or general anaesthetic. Biopsies may also be taken from other body tissues. Additional tests, including blood tests, x-rays, scans, and bone marrow samples, are then used to get more information about the type of lymphoma and how far it has spread in the body. This information is used to help decide which treatment is most appropriate for you.
Because FL is generally characterized by multiple disease relapses after responses to a variety of treatments, patients in remission should have regular visits with a physician who is familiar with their medical history as well as with the treatments they have received. Medical tests (such as blood tests and computed axial tomography [CAT] scans) may be required at various times during remission to evaluate the need for additional treatments.
Some treatments can cause long-term effects or late effects, which can vary based on duration and frequency of treatments, age, gender, and overall health of each patient at the time of treatment. A physician will check for these effects during follow-up care. Visits may become less frequent the longer the disease remains in remission.
There are various treatment options for FL based on the severity of associated symptoms as well as the rate of cancer growth. If patients show no or very few symptoms, doctors may decide not to treat it right away, an approach referred to as "watch and wait" or "watchful waiting." Studies have shown that suitable patients who follow a "watch and wait" approach have outcomes similar to those being treated early in the course of their disease.
FL is generally very responsive to radiation and chemotherapy. Radiation can provide a cure in some patients with limited disease. In more advanced stages, physicians may use one or more chemotherapy drugs or the monoclonal antibody rituximab (Rituxan), alone or in combination with other agents. Monoclonal antibodies can act more directly than chemotherapy agents by targeting particular markers found on tumor cells and recruiting immune cells to promote tumor destruction, which can increase a patient’s response to treatment. Common combination regimens include:
- R-Bendamustine (rituximab and bendamustine)
- R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone)
- R-CVP (rituximab, cyclophosphamide, vincristine, and prednisone)
Rituximab can also be used as maintenance therapy in order to prolong remission for patients with no signs of lymphoma. Another treatment sometimes used for FL is ibritumomab tiuxetan (Zevalin), which is a radioactive particle connected to an antibody that targets cancer cells.
Treatment options may change as new treatments are discovered and current treatments are improved. Therefore, it is important that patients check with their physician for any treatment updates that may have recently emerged.
Other Approved drugs to treat follicular lymphoma:
idelalisib (Zydelig) - FDA approved two treat relapsed follicular B-cell non-Hodgkin lymphoma (FL) in patients who have received at least two prior systemic therapies.
obinutuzumab (Gazyva)- FDA-approved indication: Indicated for the treatment of patients with follicular lymphoma (FL) who relapsed after, or are refractory to, a rituximab containing regimen.