What’s New in Thymus Cancer Research?

Testing thymus tumors

Researchers are looking for more accurate ways of predicting how aggressive a tumor is so the best treatment can be chosen. This includes looking at the gene changes found in the tumor cells that make them different from normal cells.

Improving imaging tests may also help doctors better decide which tumors can be safely removed with surgery.

Treating thymus tumors

Studies are looking for newer treatments, as well as different ways to use current treatments, to improve the options for people with thymus tumors.

Surgery

Traditionally, surgery has removed the thymus through a long incision in the front of the chest (a median sternotomy). This type of operation can be painful, and it often requires a long recovery time.

For smaller thymus tumors, some surgeons now operate through several smaller incisions, using long, thin surgical instruments, including one with a tiny video camera on the end. This is known as a minimally invasive thymectomy (MIT). This can be done with the surgeon either holding the tools directly (video-assisted thoracoscopic surgery, or VATS), or sitting at a control panel and moving very precise robotic arms with tools on the ends (robotic-assisted thoracoscopic surgery, or RATS). These approaches generally result in less pain after surgery (because of the smaller incisions), as well as a quicker recovery time. They might have other advantages as well. Still, it's not clear if it's better to use these techniques.

Surgeons are trying to determine which patients are the best candidates for MIT, as well as improving on the procedures themselves.

Radiation therapy

Radiation is an important part of the treatment for some thymus tumors, especially if they can't be removed completely with surgery. Unfortunately the thymus sits in the front of the chest, near many delicate and important structures. The radiation must be aimed carefully to try to avoid damaging these structures. Newer forms of radiation therapy can help do this. Some examples include:

Image-guided radiation therapy (IGRT): In this approach, an imaging test is done to create pictures of the thymus just before giving each treatment. Because the position of the thymus in the body can change slightly from day to day, IGRT can help ensure the radiation is aimed more precisely.

Motion management techniques: These can be used to help adjust for body movements during treatment, such as breathing, which might move the area that needs to be treated.

Proton beam therapy: This treatment focuses protons on the cancer, instead of x-rays. In standard radiation therapy, the x-ray beams release their energy both before and after they hit their target, so they can damage any organ along their path. But protons cause little damage to tissues they pass through and then release their energy only after traveling a certain distance. This can deliver more radiation to the cancer while doing less damage to nearby normal tissues. 

Newer types of drug treatments

Chemotherapy can often help shrink thymus cancers, but it doesn't always work, and it can have serious side effects. Other types of drugs might be helpful in some situations.

Targeted drugs

As researchers have learned more about what makes cancer cells different from normal cells, they have been able to make drugs that target these differences. These targeted drugs affect parts of cancer cells that make them different, or even the blood vessels they need to grow.

Some targeted drugs are already being used to treat thymus tumors, typically when chemo is no longer working. Many other targeted drugs are now being studied for use against thymus tumors as well.

Immunotherapy

Immunotherapy is the use of medicines to help the body's own immune system attack cancer cells. It's becoming an increasingly important part of the treatment of many types of cancer. Some studies have shown that immunotherapy might be helpful in treating thymus tumors as well.