Nasopharyngeal Cancer: Stages, Causes, Symptoms, Treatment, Survival Rate

Nasopharyngeal cancer is a rare form that grows in the neck and head region, the upper area of the throat and the backside of the nose.^[1] The nasopharynx resides under the skull and above the upper area of the mouth. The nostrils open up in the nasopharynx and while inhaling the air, it passes through the nose into it and through the throat and to lungs.^[2]

The determination of stages in Nasopharyngeal cancer is of utmost importance because the treatment and the prognosis depend on this. The stages of Nasopharyngeal cancer range from.

• Stage 0. In stage 0 of Nasopharyngeal cancer, the tumor has grown in upper area of cells that provides a lining to nasopharynx, but has not grown more than that.
• Stage I of Nasopharyngeal Cancer. The tumor has grown in the nasopharynx or might have extended to oropharynx and nasal cavity, but not more than that.
• Stage II of Nasopharyngeal Cancer. The cancer is now found in the lymph nodes around the neck area and has a positive Epstein-Barr virus that strengthens the occurrence of nasopharynx cancer. The Nasopharyngeal cancer might also have spread to the tissues of the upper regions of the throat but the bones are not yet affected.
• Stage III of Nasopharyngeal Cancer. The cancer cells, in this stage, might have invaded in the lymph nodes that are 3cm throughout the neck, behind the throat and nearby bones.
• Stage IVA of Nasopharyngeal Cancer. If the cancer reaches stage IVA, it must have grown in the salivary glands, hypopharynx, cranial nerves, has travelled outside the nasopharynx, and affected lymph nodes of 6 cm above the collarbone, in and around shoulder.
• Stage IVB of Nasopharyngeal Cancer. This is the advanced stage of Nasopharyngeal Cancer wherein the cancer has widely spread outside the nasopharynx.^[3]

There are a few possible symptoms of Nasopharyngeal Cancer, but at an early stage it might not show any signs. They are.

• Blood discharge in saliva
• A noticeable lump in the neck region
• Nose bleeding
• Repeated nasal congestion
• Ringing in the ears
• Loss in hearing
• Regular infections in the ear
• Sore throats
• Severe headaches
• Trouble in opening the mouth
• Numbness or pain in the face
• Blurred vision.

Experiencing these symptoms does not always indicate cancer as they are common symptoms to many problems. Hence a careful diagnosis is very important.^[4]

Repeated researches are yet to find out the real cause of nasopharyngeal cancer. The scientists are not very sure of the actual cause even but they have found its relation with the Epstein – Barr Virus (EBV).

People with EEBV infections in the developed countries have mononucleosis in their immune system that helps in identifying the virus and destructs it. They combat the EBV easily and recover without facing any problem. However, sometimes, EBV DNA tissues mix with the nasopharynx cells and DNA leading to an abnormal growth of the cells of nasopharynx. Yet there is not enough study to substantiate EBV as the reason behind nasopharyngeal cancer.^[5]

Excessive intake of fish and meat that are cured with salt add up to the risk of nasopharyngeal cancer. Preserved food, tobacco and alcohol might also lead to nasopharyngeal cancer, but there is not much evidence to support its strong connection with it.^[6] However, the chemicals heighten the risk of nasopharyngeal cancer.

A risk factor is something that increases the chance to adopt a certain disease. However, going through those risk factors do not really mean that the person will get the disease. Scientists have found a few risk factors for Nasopharyngeal Cancer.

• Males are more likely to be affected with nasopharyngeal cancer than females.
• The ethnicity, race and the place where the person is living puts one at risk for nasopharyngeal cancer.
• People who take more salt-cured meat or fish.
• Infection caused due to Epstein-Barr virus.
• History of a similar disease in the family.^[7]

After examining the condition and the symptoms of the patient, the doctor will know better how to go about the diagnosis. The patient might have to undergo several tests to confirm and determine the diseases and its stages.

The patients with nasopharyngeal cancer are supposed to show a prominent lump in their neck region which is a sign of the cancer having spread into the lymph nodes. A nasopharyngoscopy will be recommended where the doctor inserts a slim tube-shaped object with a camera to view the nasopharynx more clearly. If anything abnormal is detected, few other imaging tests might be done to confirm the disease and start its treatment immediately. They are.

• X-ray of the chest
• MRI
• CT scan
• Ultrasound of the nose
• Biopsy
• A complete blood count test and
• EBV testing might also be needed to carry out^[8]

Nasopharyngeal cancer can be cured properly if it is diagnosed at an early stage. The doctor must keep in mind the consequences of the treatment and its impact on the patient while planning the treatment.

There are three major kinds of treatment offered to a nasopharyngeal cancer patient. These are radiation therapy, chemotherapy, and surgery. The most commonly used is the radiation therapy with combination to chemotherapy. Surgery is very rarely carried out depending on the condition.^[9]

It is therapy where high radiation or x-rays are used to kill the cancer cells or stop them from growing and spreading. The types of radiation therapy for Nasopharyngeal cancer include.

• External Beam Radiation Therapy. A machine is placed near the body and radiations are sent towards the cancer-affected areas.
• Proton Therapy. Protons are used to kill the cancer cells. Proton therapy can also treat the skull-base tumors or to treat the nearby structures.^[10]

The drug is directly injected into the bloodstream. This is done in various ways.

• An intravenous tube is being inserted into the vein with the help of needles.
• A tablet or pill which is taken orally
• A drug shot is injected directly into the muscle, skin or directly into the cancerous tumor.

Chemotherapy either stops the growth or stops the cells from spreading to other parts. However, it really depends on the Nasopharyngeal cancer stage and condition of the patient as to how effective the chemotherapy could be. Chemotherapy is given in combination with the radiation therapy depending on the needs of the patient. Chemotherapy usually weakens the immune system of the patient.^[11]

In the surgery, the tumor and some of the healthy tissues around that region is surgically removed. It is not very easy and often not carried out because it is difficult to reach the particular area since it is located very close to the cranial nerves and blood vessels.

If the doctor suspects that the cancer has spread to the lymph nodes then a neck dissection surgery might have to be performed, that may cause serious side effects to the ear, the lips and the nearby areas. There can be numbness or weakness in that region. Hence, the doctors need to judge and examine the whole situation very carefully.

Based on the 5-years survival rate, 70% of the nasopharyngeal cancer patients survive if diagnosed in stage I, 65% percent survive in stage II, 60% in stage III and 40% in stage IV.

However, this is a generalized statistics. The prognosis of Nasopharyngeal cancer depends upon many other factors as well as the health condition of the patient being the vital one.^[12]

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