Definition and Overview
Throat cancer, as the term implies, is cancer that develops in the throat. It is also the term used to refer to cancer of the voice box and tonsils. The throat is a muscular tube that connects the mouth and nose to the windpipe and oesophagus. It is where food and liquid pass to reach the stomach.
The voice box, on the other hand, is a tube-shaped organ in the neck. It is also known as the larynx. It contains the vocal cords that a person uses to make a sound. Meanwhile, tonsils are two lymph nodes found on each side of the throat. They help prevent illnesses by stopping pathogens from entering the mouth.
Throat cancer can occur when cells in the throat, voice box, or tonsils undergo mutation. This abnormality can prevent old cells from being replaced by new cells. Over time, they can form a cancerous tumour.
Throat cancers are relatively uncommon. Based on statistics, the disease affects less than 2% of adults worldwide.
Causes of Condition
In general, cancer is caused by abnormal changes in the cells’ DNA. The DNA inside a cell contains many genes. These genes provide instructions on when new cells will form, when old cells will die, and how cells will grow and divide. Changes in the DNA can cause the cells to become unregulated. Instead of dying and being replaced by new cells at the end of their lifespan, they multiply and divide uncontrollably. This causes cancerous growths to form.
What causes abnormal changes in the cell’s DNA is unknown. However, certain risk factors have been proven to increase one’s risk of cancer. The risk factors for throat cancer are tobacco use, alcohol abuse, and gastroesophageal reflux disease (GERD). Other risk factors are the HPV virus and a diet that lacks fibre from fruits and vegetables.
Throat cancer can be either squamous cell carcinoma or adenocarcinoma. It is the former if cancer starts in the flat cells that line the throat. This is the more common type of the disease. Meanwhile, it is the latter if cancer occurs in glandular cells. This type is very rare.
The signs and symptoms of throat cancer are not very specific. This means that they can also be caused by other throat problems. These include tonsillitis and laryngitis. Symptoms include a cough that does not go away with treatment, difficulty swallowing, a palpable lump in the neck, and chronic sore throat. Other signs include the inability to speak clearly, voice hoarseness, and ear pain.
Patients are advised to see their doctors if the symptoms become persistent or do not respond to standard treatments.
Who to See and Types of Treatments Available
Throat cancer patients are treated by a cancer specialist (oncologist). The disease can be diagnosed using a thin, flexible tube called an endoscope. It is inserted into the mouth and down the throat. The attached camera transmits images to a video screen. This allows doctors to catch any sign of abnormalities. Laryngoscopy is also used to diagnose the condition. It is performed the same way as an endoscopy. But instead of an endoscope, it uses laryngoscope. It is especially helpful in diagnosing cancer of the vocal cords.
If an abnormal growth is found in the throat, a small amount of tissue is taken for a biopsy. The tissue can be taken through an open surgery in which an incision is made in the neck area. It can also be taken by inserting a needle directly into the tumour. The sample tissue is then sent to a lab to determine if the abnormal growth is cancerous or not.
If cancer is confirmed, doctors will proceed with cancer staging to determine the extent of the disease. They will use imaging tests, such as an MRI and x-rays as well as CT and PET scans.
The stage of throat cancer indicates its severity. The higher the stage, the more difficult it is to cure.
Stage 0 - There is a small tumour that has not spread beyond the throat and neck region.
Stage 1 - The tumour has grown quite large (but not more than 7cm) but still localised in the throat area.
Stage 2 - The tumour is more than 7cm and limited to the throat.
Stage 3 - Cancer cells have spread to surrounding tissue.
Stage 4 - Cancer cells have spread to distant organs.
For early-stage throat cancer, radiotherapy may be sufficient to cure the condition. This treatment kills cancer cells using high-energy beams. The beams are targeted. Thus, the therapy can minimise damage to surrounding healthy tissue. Advanced cases, on the other hand, are treated with a combination of surgery and radiotherapy.
The goal of surgery is to remove the entire tumour and keep the throat and surrounding structures intact. However, this is sometimes not possible in people with advanced throat cancer (stages 3-4). In some cases, a part of the throat, voice box, and surrounding lymph nodes are removed to make sure that no cancer cells are left behind. This increases the risk of losing the patient’s ability to speak and breathe normally. However, several treatments are available to restore speech and reconstruct any damaged structures.
Chemotherapy is also used to kill cancer cells. This treatment uses anti-cancer drugs that can be delivered directly into a vein. They can also be taken orally. Chemotherapy is usually combined with radiation therapy.
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Oropharyngeal cancer treatment. National Cancer Institute. http://www.cancer.gov/types/head-and-neck/patient/oropharyngeal-treatment-pdq.