Immunotherapy for Nasopharyngeal Cancer
The purpose of immunotherapy in nasopharyngeal cancer is to remove the cancer cells or control the growth of the cancer cells by restoring the natural function of the immune cells, T cells are stimulated and strengthened in vitro, so that after being introduced back to patient’s body, they will be able to identify the nasopharyngeal cancer cells and destroy them.
Proteins such as LMP-1, CK19, MUC-1 and a few others are presented on the surface of the nasopharyngeal cancer cells, they are recognized by the immune system as ‘foreign’ to the human body, and are supposed to be destroyed by the T cells in the immune system. However, immune system is failed in identifying these proteins in patients with lung cancer, causing uncontrolled growth of the nasopharyngeal cancer cells.
What is nasopharyngeal cancer?
Nasopharyngeal cancer is also known as nasopharyngeal carcinoma (NPC). It is a rare type of head and neck cancer. It starts in the upper part of your throat, behind the nose. This area is called the nasopharynx.
The nasopharynx is precariously placed at the base of your skull, above the roof of your mouth. Your nostrils open into the nasopharynx. When you breathe, air flows through your nose into your throat and nasopharynx, and eventually into your lungs.
Causes of nasopharyngeal cancer
Scientists are not sure what exactly causes nasopharyngeal cancer. However, the cancer has been strongly linked to the Epstein-Barr virus (EBV).
Although EBV infection is common, not everyone who has EBV will get nasopharyngeal cancer. In the U.S., most people who have had an EBV infection never have long-term problems. That’s because the body’s immune system destroys the virus.
But sometimes, genetic material (DNA) from the virus mixes with the DNA in the cells of the nasopharynx. The change in DNA causes cells to grow and divide abnormally, causing cancer. This is rare.
The risk for NPC goes up if you eat a diet rich in salt-cured fish and meat. Tobacco and alcohol also increase the risk. Some scientists believe that chemicals in these things further damage the DNA in cells.
Who gets nasopharyngeal cancer?
Fewer than one in every 100,000 people in North America gets this type of cancer, according to the American Cancer Society.
The cancer is most common in southeast China. It is also much more common in:
- Other parts of Asia
- North Africa
- Inuit populations of Alaska and Canada
- Chinese and Hmong immigrant groups in the U.S.
In the U.S., nasopharyngeal cancer has also been seen in African-Americans, Hispanics, and white people.
You are more likely to get this type of cancer if you:
- Are male
- Under age 55
- Eat a diet rich in salt-cured fish and meats
- Have a family history of nasopharyngeal cancer
- Have certain genes linked to cancer development
- Have come in contact with EBV
Some, but not all, studies have found a higher risk of nasopharyngeal cancer in people who:
- Drink a lot of alcohol
- Work around wood dust or a chemical called formaldehyde
Nasopharyngeal cancer Symptoms
Symptoms of nasopharyngeal cancer may include:
- Blurry or double vision
- Difficulty speaking, including hoarseness
- Ear infections that keep coming back
- Face pain or numbness
- Hearing loss, ringing in the ears, or a feeling of fullness in the ear
- Lump in neck or nose
- Stuffy nose
- Sore throat
Keep in mind, such symptoms are more likely to occur with many other diseases and health conditions that are far less serious than nasopharyngeal cancer.
If you have any of the above symptoms, see your doctor or nurse. Only an experienced medical person can diagnose or rule out nasopharyngeal cancer.
How nasopharyngeal cancer is diagnosed
Your doctor or nurse will examine you. This includes a detailed look at your ears, nose, and throat. You may be sent to a doctor who specializes in these areas, called an otolaryngologist.
The doctor or nurse will also feel your neck. Most patients with nasopharyngeal cancer have a lump in the neck. This is a sign that the cancer is spreading to the lymph nodes.
Small mirrors and lights or a flexible, lighted tube may be placed through your mouth or nose to help the doctor better view the nasopharynx. This is called a nasopharyngoscopy. It helps the doctor check the area for abnormal growths, bleeding, or other problems.
If the exam is abnormal, your doctor may recommend a biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope.
A biopsy may be taken during the nasopharyngoscopy. If there is a lump in your neck, the biopsy may be done by placing a very thin, hollow needle into the lump.
Imaging tests can help spot nasopharyngeal cancer or determine if it has spread. Imaging tests may include:
- Chest X-ray
- CT scan
- Ultrasound of the neck
The following tests may also be done to confirm or rule out cancer:
- Complete blood count (CBC) and other blood tests
- EBV testing
If you are diagnosed with nasopharyngeal cancer, other tests will be done to determine if and where the cancer has spread. This is called staging.
There are four stages of nasopharyngeal cancer. The lower the number, the less the cancer has spread to other parts of the body.
- Stage 1 is called early stage nasopharyngeal cancer.
- Stage 2 is called intermediate-stage nasopharyngeal cancer.
- Stages 3 and 4 are called advanced or late-stage nasopharyngeal cancer.
- If nasopharyngeal cancer returns, it is called recurrent cancer.
Treatment for nasopharyngeal cancer
If you are diagnosed with nasopharyngeal cancer, you will need regular follow-ups with your medical team before, during, and after treatment.
Your treatment will depend on many things, including:
- Location of the tumor
- Stage of the tumor
- Your overall health
Treatment may include:
Radiation Therapy . Radiation therapy uses X-rays to kill cancer cells and stop them from growing. It is usually part of the standard treatment for early stage nasopharyngeal cancer.
One type called IMRT delivers high-dose radiation directly to the tumor while minimizing damage to nearby healthy tissue. It may cause fewer side effects or complications than conventional radiation treatment to the nasopharynx, which can lead to:
- dry mouth
- inflammation of the lining of your mouth and throat
- brain stem injury
- death of healthy tissue
Surgery. Surgery can sometimes cure nasopharyngeal cancer if all of the tumor and cancer cells are removed. But the surgery can be difficult because of the tumor’s location near the skull. It may cause permanent damage to the eye and other nearby structures.
Not all people with nasopharyngeal cancer can have surgery. Your doctor will consider the location and stage of your tumor when discussing your treatment options.
Biologic drugs. Biologic drugs affect how your body’s immune system fights disease. They are also called monoclonal antibodies.
A biologic drug called bevacizumab (Avastin), blocks production of a substance called vascular endothelial growth factor (VEGF) . Sorafenib (Nexavar), and pazopanib (Votrient) are drugs that also block this protein. Studies show that patients with nasopharyngeal cancer who have lower levels of VEGF are more likely to remain disease-free after treatment. Bevacizumab is currently being evaluated to see if it will help improve your overall survival when combined with other treatments, such as chemotherapy. Other biologic drugs are also used. This includes the drug cetuximab (Erbitux), which targets a protein on the cancer cell’s surface. Other drugs that target this protein, including nimotuzumab and icotinib, have shown promising results in clinical trials.
Chemotherapy. Chemotherapy uses drugs to kill cancer cells. By itself, it is not usually helpful for treating nasopharyngeal cancer. But it may help you live longer when combined with radiotherapy or biological drugs.
Palliative therapy. At this time, there is no cure for head and neck cancer that has spread, or metastasized. The goal of treatment is to control your symptoms and make you as comfortable as possible. This is called palliative therapy.
Clinical trials. If treatment does not work, consider joining a clinical trial. Researchers are always testing new ways to treat cancer, and they need your help. Ask your doctor or nurse if there are any clinical trials on nasopharyngeal cancer in your area.
Can nasopharyngeal cancer be prevented?
Taking these steps may lower your risk of nasopharyngeal cancer:
- Eat a diet rich in fruits and vegetables
- Avoid salt-cured fish and meats
- Do not smoke
- Do not drink a lot of alcohol