What’s New in Skin Lymphoma Research?

Genetics

Scientists are making progress in learning how changes in the DNA (genes) inside normal lymphocytes can cause them to develop into lymphoma cells. Understanding these changes can provide insight into why these cells grow too quickly, live too long, and don’t develop into normal mature cells. It might also lead to new drugs that specifically target these processes.

What we now know about these DNA changes has already led to the development of highly sensitive lab tests for detecting and classifying this disease. These types of tests can help doctors choose which treatments are likely to be best for each person.

Skin-directed treatments

Several newer types of skin-directed treatments are now being studied for early-stage skin lymphomas.

Photodynamic therapy (PDT)

For this treatment, a 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 changes the drug that has collected inside the lymphoma cells, which kills 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 may limit its use to early-stage skin lymphomas that have not grown deeply into the skin. Even then, PDT might be used only if other types of skin-directed therapies are not effective. You can find out more about PDT in Photodynamic Therapy.

Topical imiquimod and resiquimod

These drugs affect a protein inside cells called TLR7. When applied to a skin lesion as a cream or gel, they can cause a local immune reaction, which can kill skin lymphoma cells. Imiquimod is already available to treat some other skin conditions, so doctors can use it off-label to treat skin lymphomas, while resiquimod is still being studied.

Targeted drugs

Targeted drugs are designed to work against parts of lymphoma cells that make them different from normal cells. Several targeted drugs have been approved to treat some types of skin lymphomas in recent years, and many more are now being studied. Researchers are also developing new targeted drugs as they learn more about what makes skin lymphoma cells different from normal cells.

Immunotherapy

Immunotherapy is the use of medicines to help a person’s own immune system attack cancer cells in the body. Some types of immunotherapy are now being used to treat some skin lymphomas, and others are being studied.

For example, immunotherapy drugs called checkpoint inhibitors work by blocking a 'checkpoint' protein on immune cells that keeps them from attacking cancer cells. These drugs have been found to be helpful in treating many types of cancer, and some of them are now being studied for use against skin lymphomas. Some early research has shown that one of these drugs might be helpful in treating some types of advanced skin lymphomas, often after other treatments have been tried. Some studies are testing these drugs along with other treatments such as radiation therapy, which might help them work better.

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 (collect) these cells before transplantation.

A lot of research is focusing on reducing graft-versus-host disease when stem cells from a donor are used (in an allogeneic transplant). 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.