What’s new in skin lymphoma research and treatment?
As noted in the section “Do we know what causes lymphoma of the skin?” scientists are making progress in understanding how changes in DNA can cause normal lymphocytes to develop into lymphoma cells. Understanding the gene changes that occur in lymphoma cells provides insight into why these cells grow too quickly, live too long, and do not develop into normal mature cells. Once this is understood, drugs may be developed that block or specifically target this process.
Our understanding of these DNA changes has already led to highly sensitive tests for detecting this disease. These tests can identify lymphoma cells based on their gene changes. For example, polymerase chain reaction (PCR) is a very sensitive test that is useful in determining if a lymphoma has been destroyed by treatment and whether a relapse is likely. These tests may help pick out those patients who may need early and more intensive treatment.
Several newer types of skin-directed treatments are now being studied for the treatment of early stage skin lymphomas.
Photodynamic therapy (PDT)
For this treatment, a light-activated drug called aminolevulinic acid (ALA) is applied to the skin lesions. A special type of laser light is then focused on the lesions. This light causes changes in the drug that has collected inside the lymphoma cells, changing it into a new chemical that can kill them.
The advantage of PDT is that it can kill cancer cells with very little harm to normal cells. But because the chemical must be activated by light, it can only kill cancer cells near the surface of the skin. This limits its use to early stage skin lymphomas that have not grown deeply into the skin. Even then, PDT might only be used if other types of skin-directed therapies are not effective. You can find out more about PDT in our document Photodynamic Therapy.
Tacrolimus is a drug that affects immune system cells such as lymphocytes, the cells that develop into lymphoma cells. Applying this drug to skin lymphomas seems to be about as effective as using topical corticosteroids, but more research is needed to help determine its safety and effectiveness.
Many clinical trials are in progress to study newer chemotherapy drugs. One example is pralatrexate (Folotyn), a drug that is already used to treat some T-cell lymphomas and has shown early promise in treating some skin lymphomas. Another drug that has shown some promise in early clinical trials is forodesine. Research on these and other new drugs continues.
Other studies are looking at ways to use drugs already known to be effective by combining them in new ways or using different doses or different sequences of these drugs.
Newer drugs known as targeted therapies have shown clear benefit in certain kinds of skin lymphoma. The drugs vorinostat (Zolinza), romidepsin (Istodax), and bortezomib (Velcade) are forms of targeted therapy that can help treat some skin lymphomas. Doctors are now studying how to use these new drugs most effectively.
Other targeted drugs are also being developed. One example is crizotinib (Xalkori), which has been shown help some patients with non-skin forms of anaplastic large cell lymphoma (ALCL). Others being studied include everolimus (Afinitor) and lenalidomide (Revlimid).
Lymphoma cells have certain chemicals on their surface. Special man-made antibodies that recognize these substances can be targeted to destroy the lymphoma cells while causing little damage to normal body tissues.
Several such drugs, including rituximab (Rituxan) and alemtuzumab (Campath), are already used to treat some skin lymphomas and are discussed in the section “Whole body (systemic) treatments for skin lymphomas.”
New monoclonal antibodies are also being developed. One example is zanolimumab (HuMax-CD4), an antibody that has shown promise in early clinical trials.
Another is brentuximab vedotin (Adcetris), an antibody that is attached to a chemotherapy drug. The antibody targets a substance on the surface of some lymphoma cells, bringing the chemo drug directly to these cells. It has already shown good results in treating some other types of lymphomas and is now being studied for certain skin lymphomas.
Stem cell transplant
High-dose chemotherapy followed by a stem cell transplant is sometimes used to treat lymphomas that no longer respond to other treatments. Researchers continue to improve stem cell transplant methods, including new ways to harvest these cells before transplantation.
Autologous transplants (using the patient’s own stem cells) have the risk of reintroducing lymphoma cells back into the patient after treatment. Researchers are testing new and improved ways to remove the last traces of lymphoma from these stem cells before they are returned to the patient. Some of the new monoclonal antibodies developed for treating lymphoma may be helpful in removing these remaining cells.
Much research is focusing on reducing graft-versus-host disease in allogeneic transplants (using stem cells from a donor). This work involves altering the transplanted T-cells so that they won’t react with the patient’s normal cells but will still kill the lymphoma cells.
Doctors know it is possible for people with cancer to develop immune responses to their cancer. In rare instances, people’s immune systems have rejected their cancers, and they have been cured. Scientists are now studying ways to boost this immune reaction using vaccines.
Unlike vaccines used to prevent infections, the purpose of these vaccines is to create an immune reaction against the lymphoma cells in patients who have very early disease or whose disease is in remission but could come back or relapse. This is a major area of research in lymphoma treatment, but it is still being tested in clinical trials. You may want to consider enrolling in one of these studies.
Last Medical Review: 03/14/2013
Last Revised: 02/11/2014