Important research into nasopharyngeal cancer (NPC) is under way in many university hospitals, medical centers, and other institutions around the world. Each year, scientists find out more about what causes the disease, how to prevent it, and how to improve treatment.

Causes

Many studies are being done to learn more about how Epstein-Barr virus (EBV) infection and other risk factors cause cells of the nasopharynx to become cancerous. Researchers are optimistic that these studies may eventually lead to vaccines to prevent NPC by avoiding EBV infection.

Recent discoveries about EBV, its interaction with nasopharyngeal cells, and the immune system's reaction to EBV have led to new blood tests that may help detect NPC early and better predict the response to treatment. These tests are now being studied in areas of the world where this cancer is common.

Treatment

New surgical techniques

Advances in the field of skull base surgery such as the use of endoscopes in the nose now allow doctors to remove some tumors from difficult areas like the nasopharynx. This type of surgery requires a specialized team that has expertise in this field. It may offer hope for some patients with recurrent NPC and patients with the keratinizing type of NPC, which often doesn't respond to radiation therapy.

New radiation therapy techniques

Recent advances in radiation therapy have helped improve the outlook for patients with NPC. Doctors can now use 3-dimensional images (obtained by CT or MRI scans) and computers to figure out how best to aim radiation at the cancer while limiting the radiation to normal tissues. This may lessen side effects. Intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery are examples of this highly-focused approach to treatment.

Another newer type of radiation uses protons instead of x-rays to kill cancer cells. Unlike x-rays, which release energy both before and after they hit their target, protons cause little damage to tissues they pass through and then release their energy after traveling a certain distance. This means that proton beam radiation may be able to deliver more radiation to the tumor and do less damage to nearby normal tissues. Although this approach is promising, the machines needed to make protons are expensive, and there are only a handful of them in use in the United States at this time.

Doctors are also studying the best schedule for giving radiation therapy. External beam radiation treatments are usually given once a day, 5 days a week, for many weeks in a row. Studies are now under way to see if schedules that either give the doses over fewer days or give smaller doses twice a day might be more effective.

Chemotherapy

Researchers continue to develop new chemotherapy drugs, new drug combinations, and new ways to give drugs that might be more effective against advanced NPC. Several newer drugs that are already used to treat other cancers, such as capecitabine, oxaliplatin, and pemetrexed, are now being studied for use against NPC as well.

Clinical trials are also testing ways to best combine chemotherapy with radiation therapy. For example, studies are comparing the effectiveness of chemotherapy given before, during, or after radiation therapy.

Targeted therapy

Drugs that target specific parts of cancer cells may prove to be useful against NPC and have fewer side effects than standard chemotherapy drugs.

The drug cetuximab (Erbitux), which targets the EGFR protein, is already being used in some cases of NPC that recur or keep growing after treatment with chemotherapy. Other drugs that target EGFR such as erlotinib (Tarceva) are also being studied against NPC.

Other newer drugs target a tumor's ability to develop new blood vessels, which they need in order to grow larger. These drugs are called angiogenesis inhibitors. Several of these drugs are now being tested for use against NPC, including bevacizumab (Avastin), sorafenib (Nexavar), and pazopanib.

T-lymphocyte treatment

NPC seems to be caused at least in part by infection with the Epstein-Barr virus (EBV). Although patients' immune systems can be shown to have reacted against EBV, this doesn't seem to be enough to kill the cancer. Researchers are trying to overcome this by removing T-lymphocytes (immune system cells) from the blood of patients with NPC and altering them in the lab to increase their numbers and their power to kill EBV. The cells are then injected back into the patients. Early results with small numbers of patients have been promising, and larger studies of this technique are now under way.

Gene therapy

Scientists have recently discovered how certain gene mutations (changes) in nasopharyngeal cells may cause them to become cancerous. Clinical trials are now testing the possibility of replacing damaged tumor suppressor genes in the cancer cells through gene therapy. This approach is still in the earliest stages of study.

Last Medical Review: 01/21/2009
Last Revised: 01/21/2009