Laryngeal cancer

Laryngeal cancer

Laryngeal cancer may also be called cancer of the larynx or laryngeal carcinoma. Most laryngeal cancers are squamous cell carcinomas, reflecting their origin from the squamous cells which form the majority of the laryngeal epithelium.
Cancer can develop in any part of the larynx, but the cure rate is affected by the location of the tumor. For the purposes of tumour staging, the larynx is divided into three anatomical regions: the glottis (true vocal cords, anterior and posterior commissures); the supraglottis (epiglottis, arytenoids and aryepiglottic folds, and false cords); and the subglottis.

Most laryngeal cancers originate in the glottis. Supraglottic cancers are less common, and subglottic tumours are least frequent.

Laryngeal cancer may spread by direct extension to adjacent structures, by metastasis to regional cervical lymph nodes, or more distantly, through the blood stream. Distant metastates to the lung are most common.

Causes

There is no single cause of laryngeal cancer. It is likely that several factors combine to cause it. Not all of these factors are known, but research is going on continually into possible causes.

Smoking and heavy drinking of alcohol (especially spirits) greatly increase the risk of developing laryngeal cancer.

Laryngeal cancer occurs mainly in middle-aged and older people, but it can occur in younger people who started smoking at an early age. It is more common in men than in women.

Risk factors

Smoking is the most important risk factor for laryngeal cancer. Heavy chronic consumption of alcohol, particularly alcoholic spirits, is also significant. When combined, these two factors appear to have a synergistic effect.Some other quoted risk factors are likely, in part, to be related to prolonged alcohol and tobacco consumption. These include low socioeconomic status, male sex, and age greater than 55 years.

People with a previous history of head and neck cancer are known to be at higher risk (about 25%) of developing a second cancer of the head, neck, or lung. This is mainly because in a significant proportion of these patients, the aerodigestive tract and lung epithelium have been exposed chronically to the carcinogenic effects of alcohol and tobacco. In this situation, a field change effect may occur, where the epithelial tissues start to become diffusely dysplastic with a reduced threshold for malignant change. This risk may be reduced by quitting alcohol and tobacco.

ymptoms

The symptoms of laryngeal cancer depend on the size and location of the tumor. Symptoms may include the following:

*Hoarseness or other voice changes
*A lump in the neck
*A sore throat or feeling that something is stuck in the throat
*Persistent cough
*Stridor
*Bad breath
*Earache

Incidence

5 in 100,000 (12,500 new cases per year) in USA.cite web | author = Samuel W. Beenken, MD | title =Laryngeal Cancer (Cancer of the larynx)| work =Laryngeal Cancer (Cancer of the larynx) | url=http://www.health.am/cr/laryngeal-cancer/ | publisher=Armenian Health Network, Health.am | accessdate=2007-03-22] The American Cancer Society estimates that 9,510 men and women (7,700 men and 1,810 women) will be diagnosed with and 3,740 men and women will die of laryngeal cancer in 2006.

Laryngeal cancer is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that laryngeal cancer affects fewer than 200,000 people in the U.S.cite web | title =Annual Report on the Rare Diseases and Conditions Research| url=http://rarediseases.info.nih.gov/ | publisher=National Institutes of Health | accessdate=2007-03-22]

Each year, about 2,200 people in the U.K. are diagnosed with laryngeal cancer.cite web | title =Causes of laryngeal cancer| url=http://www.cancerbackup.org.uk/Cancertype/Larynx/Causesdiagnosis/Causes | publisher=Cancerbackup-cancerbackup.org.uk | accessdate=2007-03-22]

Diagnosis

Diagnosis is made by the doctor on the basis of a careful medical history, physical examination, and special investigations which may include a chest x-ray, CT or MRI scans, and tissue biopsy. The examination of the larynx requires some expertise, which may require specialist referral.

The physical exam includes a systematic examination of the whole patient to assess general health and to look for signs of associated conditions and metastatic disease. The neck and supraclavicular fossa are palpated to feel for cervical adenopathy, other masses, and laryngeal crepitus. The oral cavity and oropharynx are examined under direct vision. The larynx may be examined by indirect laryngoscopy using a small angled mirror with a long handle (akin to a dentist's mirror) and a strong light. Indirect laryngoscopy can be highly effective, but requires skill and practice for consistent results. For this reason, many specialist clinics now use fibre-optic nasal endoscopy where a thin and flexible endoscope, inserted through the nostril, is used to clearly visualise the entire pharynx and larynx. Nasal endoscopy is a quick and easy procedure performed in clinic. Local anaesthetic spray may be used.

If there is a suspicion of cancer, biopsy is performed, usually under general anaesthetic. This provides definitive histological proof of cancer type and grade. If the lesion appears to be small and well localised, the surgeon may undertake excision biopsy, where an attempt is made to completely remove the tumour at the time of first biopsy. In this situation, the pathologist will not only be able to confirm the diagnosis, but can also comment on the completeness of excision, i.e., whether the tumour has been completely removed. A full endoscopic examination of the larynx, trachea, and esophagus is often performed at the time of biopsy.

For small glottic tumours further imaging may be unnecessary. In most cases, tumour staging is completed by scanning the head and neck region to accurately assess the local extent of the tumour and any pathologically enlarged cervical lymph nodes.

The final management plan will depend on the specific site, stage (tumour size, nodal spread, distant metastasis), and histological type. The overall health and wishes of the patient must also be taken into account.

Treatment

Specific treatment depends on the location, type, and stage of the tumour. Treatment may involve surgery, radiotherapy, or chemotherapy, alone or in combination. This is a specialised area which requires the coordinated expertise of dedicated ear, nose and throat (ENT) surgeons (otolaryngologists) and oncologists.

References

External links

* [http://www.cancerhelp.org.uk/help/default.asp?page=5606 Staging cancer of the larynx]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • laryngeal cancer — Cancer that forms in tissues of the larynx (area of the throat that contains the vocal cords and is used for breathing, swallowing, and talking). Most laryngeal cancers are squamous cell carcinomas (cancer that begins in flat cells lining the… …   English dictionary of cancer terms

  • laryngeal cancer — Malignant tumour of the larynx. The larynx is affected by both benign and malignant tumours. Squamous cell carcinoma, the most common laryngeal malignancy, is associated with smoking and alcohol consumption; it is more common in men. Prolonged… …   Universalium

  • stage I laryngeal cancer — Cancer is found only in the area where it started. Stage I laryngeal cancer depends on where cancer is found in the larynx. If it started in the supraglottis, then cancer is in one area of the supraglottis only and the vocal cords can move… …   English dictionary of cancer terms

  • stage III laryngeal cancer — In stage III laryngeal cancer, one of the following is found: (1) cancer is in the larynx only and the vocal cords do not move normally; cancer may have spread to tissues next to the larynx; cancer may have spread to one lymph node on the same… …   English dictionary of cancer terms

  • stage II laryngeal cancer — Cancer that is found in the larynx. The exact definition of stage II depends on where the cancer started. If it started in the supraglottis, then cancer is in more than one area of the supraglottis or glottis or region near the supraglottis. If… …   English dictionary of cancer terms

  • stage IV laryngeal cancer — The cancer has spread to tissues around the larynx, such as the pharynx or the tissues in the neck. The lymph nodes in the area may contain cancer; the cancer has spread to more than one lymph node on the same side of the neck as the cancer, to… …   English dictionary of cancer terms

  • stage IVA laryngeal cancer — Stage IV is divided into stages IVA, IVB, and IVC. In stage IVA, one of the following is found: (1) cancer has spread through the thyroid cartilage and/or has spread to tissues beyond the larynx such as the neck, trachea, thyroid, or esophagus;… …   English dictionary of cancer terms

  • stage IVB laryngeal cancer — Stage IV is divided into stages IVA, IVB, and IVC. In stage IVB, one of the following is found: (1) cancer has spread to the space in front of the spinal column and surrounds the carotid artery, or has spread to parts of the chest and may have… …   English dictionary of cancer terms

  • stage IVC laryngeal cancer — Stage IV is divided into stages IVA, IVB, and IVC. In stage IVC, cancer has spread beyond the larynx to distant parts of the body …   English dictionary of cancer terms

  • Laryngeal paralysis — in animals is a condition in which the nerves and muscles that move one or both aretynoid cartilages of the larynx cease to function, and instead of opening during vigorous inspiration and closing during swallowing, the aretynoids hang loosely in …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”