Before follicular lymphoma is treated, the cancer is staged to help decide on the most suitable treatment approach as well as to predict patient outcome.
Treatment can cure some people with stage I or early stage II follicular lymphoma. Surgery is not usually opted for as although it may remove the bulk of the cancerous lymph tissue, cancer cells may remain and proliferate, giving rise to a relapse.
Early stage follicular lymphomas are usually treated with radiotherapy, where high energy beams of radiation are used to kill the lymphoma cells. This therapy is generally used to target small areas in the lymph nodes. However, radiation may also be delivered to large areas in order to reduce symptoms, even when the cancer is more advanced.
Sometimes the radiotherapy may be combined with a short course of chemotherapy or immunotherapy. Radiotherapy is usually delivered over 12 short daily sessions, typically lasting 5–20 minutes.
For people with more advanced follicular lymphoma but who are not experiencing symptoms, a “wait and watch approach” may be adopted. The patient is not given any active treatment but is closely monitored for growth or spread of the cancer.
Advanced stage disease that does present with symptoms is usually treated with chemotherapy and immunotherapy. Chemotherapy can be given by mouth (orally) or given into a vein (intravenously). Repeated courses or cycles are necessary to kill cells that are dividing, with more cells being killed with each cycle of treatment. Once the cancer is under control, the patient is said to be in remission.
Chemotherapy is often given in combination with the monoclonal antibody rituximab. Rituximab is an antibody therapy that targets a protein called CD20 that is present on the cancerous cells in follicular lymphoma. Once rituximab binds to CD20, the cancer cell is flagged up for attack by the body’s immune system.
A chemotherapy regimen referred to as CHOP is often given in combination with rituximab (R-CHOP). The acronym CHOP denotes the use of three intravenous drugs (cyclophosphamide, hydroxydaunorubicin/doxorubicin and vincristine/onconovin) and the oral drug prednisolone. Doxorubicin is usually eliminated from the regimen in cases where people have a history of cardiovascular disease and a regimen called R-CVP is administered instead (rituximab plus cyclophosphamide, vincristine, prednisolone).
If a patient relapses, other treatment approaches may be attempted such as alternative chemotherapy agents or monoclonal antibodies. Stem cell transplantation is another treatment option.
Radioimmunotherapy is a new form of treatment for follicular lymphoma, where the cancer cells are tagged using a radioactive particle attached to an antibody (usually to CD20). The treatment (90Y-ibritumomab or Zevalin®) is available in some places on an experimental basis.