Relapsed/Refractory Follicular Lymphoma

Follicular lymphoma is a type of non-Hodgkin lymphoma that involves abnormal growth of the B-lymphocytes (B-cells). The lymphocytes with abnormal cell growth can travel around the body and form tumors, known as lymphoma, in the lymph nodes, spleen, bone marrow, blood or other organs. It is usually slow to grow but is not curable in most cases.

Relapsed or refractory follicular lymphoma occurs when the cancer is not cured with primary treatment or returns after a period of remission. Patients may notice signs of the cancerous growth, such as fatigue, loss of appetite, or enlarged lymph nodes.

Relapsed Follicular Cancer

A relapse is a term used to describe the return of a disease after treatment. In follicular cancer, this means that the abnormal cell growth initially improves but then returns after treatment. As a result, secondary therapies may be needed to treat the disease.

Refractory Follicular Cancer

Refractory is a term used to describe a disease that does not respond to treatment. In follicular cancer, this means that the abnormal cell growth does not improve sufficiently with the initial treatment for remission. As a result, secondary therapies may be needed to treat the disease.

Factors for Treatment Decision

There are several factors that will influence the treatment decisions for a patient with relapsed or refractory follicular cancer. These include:

• Previous treatment regimen
• Duration of remission from the last treatment
• Symptoms of the cancer

In most cases, the secondary treatment should be different from the initial treatment method to increase the likelihood of successful remission.

Treatment Options

There are several therapies that may be used in the treatment of relapsed or refractory follicular lymphoma, including chemotherapy, radiation, monoclonal antibodies, and radioimmunotherapy.

High-dose chemotherapy, with an autologous or allogeneic stem cell transplant, can be effective in the treatment of relapsed follicular lymphoma to prolong the period of remission.

Radiation therapy involves the use of radiation waves directed toward the lymphoma to destroy the cancerous cells and induce remission.

Monoclonal antibodies such as rituximab (Rituxan), used either alone or in combination with other treatment methods, may also be effective.

Radioimmunotherapy (alone or in combination with chemotherapy): Involves both radiation and immune system to destroy cancer cells, by way of attaching a radioactive compound to the monoclonal antibody medication, thus delivering radiation directly to the lymphoma cells. This occurs because the monoclonal antibody binds to the CD20 antigen protein on the surface of the lymphocyte cells.

Radioimmunotherapy medications are very effective in inducing remission that lasts when used in an appropriate manner. Commercially available radioimmunotherapy drugs include:

• Iodine 131 tositumomab (Bexxar)
• Y90 ibritumomabtiuxetan (Zevalin)

Bendamustine (Treanda) can also sometimes be used in the treatment of relapsed or refractory lymphoma.

Transformed Lymphoma

Approximately one-third of patients with follicular lymphoma will have a histologic transformation, also known as a transformed lymphoma. This is usually more aggressive and requires a more aggressive treatment approach. Treatment may involve high-dose chemotherapy, in combination with a monoclonal antibody medication, such as rituximab. Alternative treatment options include radiation therapy and radioimmunotherapy.

References

• http://www.lymphoma.org/atf/cf/%7B0363cdd6-51b5-427b-be48-e6af871acec9%7D/FOLLICULARRE2010.PDF
• http://www.gazyva.com/fl/what-is-fl
• http://jco.ascopubs.org/content/early/2015/07/08/JCO.2015.62.3256.full
• http://www.texasoncology.com/types-of-cancer/non-hodgkins-lymphoma/follicular-lymphoma/relapsed-follicular-nhl
• http://www.medscape.org/viewarticle/757472