What is Nasopharyngeal Cancer?

Nasopharyngeal cancer (NPC) develops in the nasopharynx, an area in the back of the nose toward the base of skull. The nasopharynx is a box-like chamber about 1½ inches on each edge. It lies just above the soft palate, just in back of the entrance into the nasal passages. Although it is considered an oral cancer, nasopharyngeal cancer is different from most oral cancers. It tends to spread widely, is not often treated by surgery, and has different risk factors from most oral cancers.

Several types of tumors can develop in the nasopharynx. Some of these tumors are benign (non-cancerous). Others are malignant (cancerous), and these can penetrate into surrounding tissues and spread to other parts of the body.

Who is at risk for Nasopharyngeal Cancer?

NPC is relatively rare in most parts of the world. In North America, it occurs in 7 out of every one million persons. This may add up to about 2000 cases a year in the United States. However, this cancer is much more common in areas of Asia and North Africa, and in particular, in Southeast China, where it is a fairly common cancer. It is also more common among Inuits of Alaska. It is also found more often in immigrant groups in the United States, such as recent Chinese immigrants and those from Southeast Asia such as the Hmong. In the last few years the rate at which Americans, including Chinese immigrants, have been developing this cancer has been slowly dropping.

NPC most often affects people beginning at age 30 and older but can be seen in children. About half of patients are less than 55 years old. NPC is found in men about twice as often as in women. It is 50% more common in blacks than in whites.

Scientists have identified certain risk factors that make a person more likely to develop NPC.

• Diet: diets very high in salt-cured fish and meat.
  
  
• Epstein-Barr virus infection: in ways that are not completely understood there is a complex link between EBV infection and NPC. EBV infection alone is not sufficient to cause NPC, since this cancer is rare and infection with this virus so common.
  
  
• Genetic factors: recent studies have found that people with certain inherited tissue types are at increased risk of developing NPC.
  
  
• Also, family members of people with NPC are more likely to get this cancer. Whether this is due to environmental factors or genetic ones, or both, is not known.
  
  

How is Nasopharyngeal Cancer diagnosed?

This cancer is diagnosed when a patient complains of symptoms or finds a lump in the neck. Some patients with NPC have no symptoms at all.

• Medical history and physical examination: a complete medical history (interview) to check for risk factors and symptoms, a physical exam to look for signs of NPC with special attention to any visible abnormality in the nasopharynx, lymph node enlargement in the neck area, facial numbness or muscle weakness (possibly due to spread of cancer into nerves), and any other associated health problems.
  
  
• Examinations of the nasopharynx: direct nasopharyngoscopy uses special mirrors and lights in fiberoptic scopes (flexible, lighted, narrow tubes inserted through the mouth or nose). These instruments allow the doctor to look inside the nasopharynx for abnormal growths, bleeding, or other signs of disease. If a suspicious growth is found, the doctor will obtain a sample of tissue, biopsy. The tissue specimen is sent to a laboratory, and a pathologist (a doctor specializing in laboratory diagnosis of diseases) looks at the tissue under a microscope. If cancer cells are present, the pathologist sends back a report describing the type of the cancer.
  
  
• Chest x-ray: done to see if your cancer has spread to your lungs. This is very unlikely unless your cancer is far advanced.
  
  
• Computed tomography (CT): produces detailed cross-sectional images of your body. Instead of taking one picture, as does a conventional x-ray, a CT scanner takes many pictures as it rotates around you. A computer then combines these pictures into an image of a slice of your body. This will provide information about the size, shape, and position of a tumor and can help find enlarged lymph nodes that might contain cancer. CT scans or MRIs are important for finding cancer that has spread into the bones at the base of the skull.
  
  
• Magnetic resonance imaging (MRI): radio waves and strong magnets instead of x-rays. This is helpful in detecting cancer that has spread to the brain, spinal cord or into the bones at the base of the skull.
  
  
• Positron emission tomography (PET): body absorb large amounts of the radioactive sugar and a special camera can detect the radioactivity. This test is useful to see if the cancer has spread to lymph nodes. Newer devices combine a CT scan and a PET scan to even better pinpoint the tumor.
  
  
• Blood tests: the blood level of EBV before and after treatment may be useful to determine a patient's outcome. They may also suggest the possibility of liver metastasis or bone metastasis, prompting additional testing.
  
  
• Fine needle aspiration (FNA): type of biopsy can be done in the doctor's office or clinic.The doctor places a thin needle directly into the mass for about 10 seconds and withdraws cells and a few drops of fluid. These cells are then viewed under a microscope to determine if they appear cancerous (malignant).
  
  

How is Nasopharyngeal Cancer treated?

The options for treatment of NPC are radiation therapy, chemotherapy, and occasionally surgery. In some cases, the best approach involves 2 or more of these strategies.

Radiation therapy (External beam radiation therapy or Brachytherapy) is the main form of treatment for NPC because most cases are the radiation-sensitive type, the non-keratinizing and undifferentiated varieties. Radiation therapy uses a beam of high-energy X-rays or particles to destroy cancer cells or slow their rate of growth. Several types of radiation therapy are used to treat the main nasopharyngeal mass and nearby lymph nodes. Even if the lymph nodes are not abnormally firm or large, radiation is still used in case a few cancer cells have spread to the lymph nodes. If the lymph nodes are known to contain metastasis from NPC, higher radiation doses are used.

Chemotherapy is the use of special drugs (swallowed or injected) for treating cancer. Chemotherapy can kill rapidly growing cells such as cancer cells. Some chemotherapy drugs also make cells more vulnerable to radiation. Chemotherapy often involves the use of 2 or more drugs, called combination chemotherapy. Chemotherapy is often used together with radiation therapy as the first treatment for more advanced stages of this cancer. It is also used alone for patients whose NPC has spread to distant organs such as the lungs, bones, or liver. The main drugs used in the treatment of NPC are cisplatin, 5-fluorouracil (5-FU), bleomycin, methotrexate, doxorubicin, and epirubicin. Some of the combinations used most often are cisplatin and 5-FU; cisplatin, 5-FU, and bleomycin; or cisplatin, epirubicin, and bleomycin.

Surgery is seldom done for patients with nasopharyngeal cancer. New surgical techniques can completely remove some nasopharyngeal tumors, but this strategy is appropriate only for a relatively small number of patients. Doctors perform these complex procedures only in specialized centers. The advantages of surgical removal include the ability of the pathologist to examine the entire cancer, as well as additional tissue removed during surgery, and of the surgeon to repair/reconstruct the cancer site.

A CT-guided endoscopic approach in most cases can achieve a similar extent of resection as most open approaches and can provide improved visualization, decreased tissue damage, fewer wound related complications, and improved cosmetic appearance. In this series, we report the first American experience with endoscopic nasopharyngectomy along with a methodical approach towards the diagnosis and treatment of recurrent NPC.

Our Study

The standard treatment of recurrent nasopharyngeal carcinoma (NPC) has been to re-irradiate or perform open nasopharyngectomy. Surgery can have better outcomes than radiation long term. Endoscopic nasopharyngectomy can have better survival than re-irradiation with potentially lower morbidity than open approaches. We review our series of endoscopic CT-guided nasopharyngectomies in the treatment of recurrent NPC.

We performed a retrospective review of 13 patients who presented to us with a recurrence of NPC after having chemotherapy and/or radiation treatment. All patients had endoscopic CT-guided nasopharyngectomy and were followed with repeat PET scans, MRIs and/or biopsies. Only 5 patients had complete records, and were used for analysis.

There were a total 3 male and 2 female patients with an average age of 44 years. All 5 patients are currently alive. 1 patient had a complication of epistaxis which required endoscopic control and embolization. There was 1 intra-operative CSF leak that was repaired without post-op complications. 3 patients had a recurrence of their cancer which required further intervention.

The average time of disease free survival after the first surgery was 13.2 (range 9-18) months.

The average time of overall survival after the first surgery was 16.4 (range 9-25) months.

The average time of overall survival since date of diagnosis was 41.2 (range 22-58) months.