I. Etiology
The cause of thyroid cancer is not known. Genetic mutations (gene mutations) in thyroid cells can cause thyroid cancer. Mutations cause the cells to grow and multiply rapidly. These cells also lose the ability to die that normal cells have. Abnormal thyroid cells accumulate and form tumors. The abnormal cells can invade adjacent tissues and spread throughout the body.
The type of thyroid cancer determines the subsequent treatment and prognosis. Types of thyroid cancer include.
1. Papillary thyroid cancer. The most common type of thyroid cancer, papillary carcinoma originates from follicular cells that produce and store thyroid hormones. Papillary thyroid cancer can occur at any age, but is more common in people between the ages of 30 and 50
2. follicular thyroid cancer. Follicular carcinoma also originates from the follicular cells of the thyroid gland. It is more likely to occur in people over 50 years of age. Eosinophilic thyroid carcinoma is a rare and potentially more aggressive form of follicular thyroid cancer.
3. Medullary thyroid carcinoma. Medullary thyroid carcinoma originates from the thyroid C cells that produce calcitonin. High levels of calcitonin in the blood can detect very early medullary thyroid cancer. Certain genetic syndromes increase the risk of medullary thyroid cancer, although this genetic link is uncommon.
4. Undifferentiated thyroid cancer. Undifferentiated thyroid cancer is a rare and fast-growing cancer that can be very difficult to treat. Undifferentiated thyroid cancer usually occurs in adults over 60 years of age
5. Thyroid lymphoma. Thyroid lymphoma is a rare form of thyroid cancer that starts in the cells of the thyroid immune system and grows very rapidly. Thyroid lymphoma is usually seen in older adults.
Risk factors
Factors that increase the risk of thyroid cancer include
1. Women. More women than men develop thyroid cancer.
2. Exposure to high levels of radiation. Examples include head and neck radiation therapy and radioactive fallout from nuclear power plant accidents or nuclear weapons testing.
3. certain genetic syndromes. Genetic syndromes that can increase the risk of thyroid cancer include familial medullary thyroid cancer, multiple endocrinomatosis and familial adenomatous polyposis.
III. Complications
Recurrence of thyroid cancer
Despite treatment, thyroid cancer may recur, even if the thyroid gland has been removed. Thyroid cancer may recur if tiny cancer cells have spread outside the thyroid gland before it is removed. Thyroid cancer recurs most often in the first 5 years after surgery, but can also recur decades after initial thyroid cancer treatment.
The location of thyroid cancer recurrence may be.
1. lymph nodes in the neck.
2. small pieces of thyroid tissue left over from surgery.
3. other parts of the body.
Recurrence of thyroid cancer can be treated medically. Your doctor may recommend regular blood tests or thyroid scans to detect signs of thyroid cancer recurrence.