Nasopharyngeal Carcinoma

Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma is cancer that occurs in the nasopharynx, which is located behind your nose and above the back of your throat. Nasopharyngeal carcinoma is difficult to detect early. That’s probably because the nasopharynx isn’t easy to examine and symptoms of nasopharyngeal carcinoma mimic those of other more common conditions. Treatment for nasopharyngeal carcinoma usually involves radiation therapy, chemotherapy or a combination of the two. You can work with your doctor to determine the exact approach depending on your particular situation.

• The throat (pharynx) is a muscular tube that runs from the back of your nose down into your neck.
• It contains three sections: the nasopharynx, oropharynx and laryngopharynx, which is also called the hypopharynx.

Symptoms

In its early stages, nasopharyngeal carcinoma may not cause any symptoms. Possible noticeable symptoms of nasopharyngeal carcinoma include:

• A lump in your neck caused by a swollen lymph node
• Blood in your saliva
• Bloody discharge from your nose
• Nasal congestion
• Hearing loss
• Frequent ear infections
• Headaches

When to see a doctor

Early nasopharyngeal carcinoma symptoms may not always prompt you to see your doctor. However, if you notice any unusual and persistent changes in your body, such as unusual nasal congestion, that don’t seem right to you, see your doctor.

Causes

Cancer begins when one or more genetic mutations cause normal cells to grow out of control, invade surrounding structures and eventually spread (metastasize) to other parts of the body. In nasopharyngeal carcinomas, this process begins in the squamous cells that line the surface of the nasopharynx. Exactly what causes the gene mutations that lead to nasopharyngeal carcinoma isn’t known, though factors, such as the Epstein-Barr virus, that increase the risk of this cancer have been identified. However, it isn’t clear why some people with all the risk factors never develop cancer, while others who have no apparent risk factors do.

Risk factors

Researchers have identified some factors that appear to increase your risk of developing nasopharyngeal carcinoma, including:

• Sex. Nasopharyngeal carcinoma is more common in men than it is in women.
• Race. This type of cancer more commonly affects people in Asia and northern Africa.
• Age. Nasopharyngeal cancer can occur at any age, but it is most commonly diagnosed in adults between the ages of 30 and 50.
• Salt-cured foods. Chemicals released in steam when cooking salt-cured foods, such as fish and preserved vegetables, may enter the nasal cavity, increasing the risk of nasopharyngeal carcinoma. Being exposed to these chemicals at an early age may increase the risk even more.
• Epstein-Barr virus. This common virus usually produces mild signs and symptoms, such as those of a cold. Sometimes it can cause infectious mononucleosis. Epstein-Barr virus is also linked to several rare cancers, including nasopharyngeal carcinoma.
• Family history. Having a family member with nasopharyngeal carcinoma increases your risk of the disease

Complications

Nasopharyngeal carcinoma complications can include:

• Cancer that grows to invade nearby structures. Advanced nasopharyngeal carcinoma can cause complications if it grows large enough to invade nearby structures, such as the throat, bones and brain.
• Cancer that spreads to other areas of the body. Nasopharyngeal carcinoma frequently spreads (metastasizes) beyond the nasopharynx. Most people with nasopharyngeal carcinoma have regional metastases. That means cancer cells from the initial tumour have migrated to nearby areas, such as lymph nodes in the neck. Cancer cells that spread to other areas of the body (distant metastases) most commonly travel to the bones, lungs and liver.

Tests and diagnosis

Tests and procedures used to diagnose nasopharyngeal carcinoma include:

• Physical exam. Diagnosing nasopharyngeal carcinoma usually begins with a general examination. Your doctor will ask questions about your symptoms. He or she may press on your neck to feel for swelling in your lymph nodes.
• Exam using a camera to see inside your nasopharynx. If nasopharyngeal carcinoma is suspected, your doctor may recommend a nasal endoscopy. This test uses a thin, flexible tube with a camera on the end to see inside your nasopharynx and look for abnormalities. The camera may be inserted through your nose or through the opening in the back of your throat that leads up into your nasopharynx. Nasal endoscopy may require local anaesthesia.
• Test to remove a sample of suspicious cells. Your doctor may also use the endoscope or another instrument to take a small tissue sample (biopsy) to be tested for cancer.

Tests to determine the extent of the cancer Once the diagnosis is confirmed, your doctor orders other tests to determine the extent (stage) of the cancer, such as imaging tests. Imaging tests may include computerized tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET) and X-ray. Once your doctor has determined the extent of your cancer, a Roman numeral that signifies its stage is assigned. The stage is used along with several other factors to determine your treatment plan and your prognosis. A lower numeral means the cancer is small and confined to the nasopharynx. A higher numeral means cancer has spread beyond the nasopharynx to lymph nodes in the neck or to other areas of the body. The stages of nasopharyngeal cancer range from I to IV.

Treatment

You and your doctor work together to devise a treatment plan based on several factors, such as the stage of your cancer, your treatment goals, your overall health and the side effects you’re willing to tolerate. Treatment for nasopharyngeal carcinoma usually begins with radiation therapy or a combination of radiation and chemotherapy.

Radiation therapy

Radiation therapy uses high-powered energy beams, such as X-rays, to kill cancer cells. Radiation therapy for nasopharyngeal carcinoma is usually administered in a procedure called external beam radiation. During this procedure, you’re positioned on a table and a large machine is maneuvered around you, directing radiation to the precise spot where it can target your cancer. For small nasopharyngeal tumours, radiation therapy may be the only treatment necessary. In other situations, radiation therapy may be combined with chemotherapy.

Radiation therapy carries a risk of side effects, including temporary skin redness, hearing loss and dry mouth. Another type of radiation therapy, an internal form of radiation (brachytherapy), is sometimes used in recurrent nasopharyngeal carcinoma. With this treatment, radioactive seeds or wires are positioned in the tumour or very close to it.

Chemotherapy

Chemotherapy is a drug treatment that uses chemicals to kill cancer cells. Chemotherapy drugs can be given in pill form, administered through a vein or both. Chemotherapy may be used to treat nasopharyngeal carcinoma in three ways:

• Chemotherapy at the same time as radiation therapy. When the two treatments are combined, chemotherapy enhances the effectiveness of radiation therapy. This combined treatment is called concomitant therapy or chemoradiation. However, side effects of chemotherapy are added to the side effects of radiation therapy, making concomitant therapy more difficult to tolerate.
• Chemotherapy after radiation therapy. Your doctor might recommend chemotherapy after radiation therapy or after concomitant therapy. Chemotherapy is used to attack any remaining cancer cells in your body, including those that may have broken off from the original tumour and spread elsewhere. Some controversy exists as to whether additional chemotherapy actually improves survival in people with nasopharyngeal carcinoma. Many people who undergo chemotherapy after concomitant therapy are unable to tolerate the side effects and must discontinue treatment.
• Chemotherapy before radiation therapy. Neoadjuvant chemotherapy is chemotherapy treatment administered before radiation therapy alone or before concomitant therapy. More research is needed to determine whether neoadjuvant chemotherapy can improve survival rates in people with nasopharyngeal carcinoma.

• What chemotherapy drugs you receive and how often will be determined by your doctor. The side effects you’re likely to experience will depend on which drugs you receive.

Surgery

Surgery is not often used as a treatment for nasopharyngeal carcinoma. Surgery may be used to remove cancerous lymph nodes in the neck. In certain cases, surgery may be used to remove a tumour from the nasopharynx. This usually requires surgeons to make an incision in the roof of your mouth in order to access the area to remove the cancerous tissue.