thyroid cancer

Definition of thyroid cancer: Cancer that forms in the thyroid gland (an organ at the base of the throat that makes hormones that help control heart rate, blood pressure, body temperature, and weight). Four main types of thyroid cancer are papillary, follicular, medullary, and anaplastic thyroid cancer. The four types are based on how the cancer cells look under a microscope

Signs and Symptoms
Thyroid cancer is more common among women than men and accounts for only 1 percent of all cancers diagnosed in the United States. Most thyroid cancers grow slowly but certain types can be aggressive.
There are four major types of thyroid gland cancer -- anaplastic, follicular, medullary and papillary. These types of thyroid cancer look differently under a microscope and generally grow at varying rates.
· Anaplastic cancer: Anaplastic cancer is the fastest growing type of thyroid cancer. The cancer cells are extremely abnormal and spread rapidly to other parts of the body. Anaplastic cancers make up only about 2 percent of all thyroid cancers and are generally difficult to cure.
· Follicular cancer: This type of cancer also develops in thyroid cells that produce iodine-containing hormones. Most follicular cancers can be cured. About 10 percent to 30 percent of thyroid cancers are follicular cancers. These cancers are well differentiated, meaning slow growing and contain cells that are similar to healthy thyroid cells.
· Medullary cancer: Medullary cancer is more difficult to control than papillary and follicular thyroid cancer. The cells involved in medullary cancers produce calcitonin, a hormone that does not contain iodine. About 5 to 7 percent of all thyroid cancers are medullary cancers. Of the four types of thyroid cancer, only medullary thyroid cancer can be inherited, which is caused by an alteration in the RET gene. Individuals who inherit this alteration are almost certain to develop medullary thyroid cancer at some time in their lives.
· Papillary cancer: This type of thyroid cancer develops in cells that produce thyroid hormones containing iodine. Papillary cancer is well-differentiated, meaning that it grows very slowly and contains cells that are similar to healthy thyroid cells. Doctors usually can treat these cancers successfully, even when cancer cells have spread to nearby lymph nodes. Papillary cancers account for about 60 percent to 80 percent of all thyroid cancers and have a favorable prognosis.
The most common symptom of thyroid cancer is a lump, or nodule, that can be felt in the thyroid gland or neck. Other symptoms are rare. Pain is seldom an early warning sign of thyroid cancer. You may have a tight or full feeling in the neck, difficulty breathing or swallowing, hoarseness or swollen lymph nodes.
Throat Cancers
Signs and Symptoms
Cancers that involve the throat, base of the tongue, tonsil, pharynx, or tube that extends from the nasal passages to the mouth to the esophagus and sinus are called oropharyngeal and hypopharyngeal cancers.
Symptoms of throat cancer may include:
§ A sore throat that does not go away
§ Cough
§ Pain or difficulty swallowing
§ Weight loss for no known reason
§ Ear pain
§ A lump in the back of the mouth, throat or neck
§ Advanced tumors may invade the voice box, causing hoarseness or breathing difficulty
§ Bleeding from the throat or blood-tinged sputum
Risk factors for developing throat cancer may include:
§ Smoking tobacco
§ Heavy alcohol use
§ A diet low in fruits and vegetables
§ Drinking maté, a stimulant drink common in South America
§ Chewing betel quid, a stimulant commonly used in parts of Asia
§ Being infected with human papillomavirus (HPV)