The most common type of thyroid carcinoma is papillary carcinoma. About 80% to 85% of thyroid cancers are papillary carcinomas (also called papillary cancer or papillary adenocarcinoma). Papillary carcinomas develop from the thyroid follicle cells and typically grow very slowly. Usually they occur in only one lobe of the thyroid gland, but about 10% to 20% of the time both lobes are involved. Several different variants (subtypes) of papillary carcinoma can be recognized under the microscope. These include the follicular variant, tall cell variant, columnar cell variant and diffuse sclerosing variant. The usual form of papillary adenocarcinoma and the follicular variant have the same outlook for survival (prognosis), and treatment is the same for both. The other variants tend to spread more quickly and have a worse prognosis. Even though papillary cancer grows slowly, it often spreads early to the lymph nodes in the neck. Fortunately, most people with papillary cancer do not die from it.
Papillary carcinoma typically arises as an irregular, solid or cystic mass that arises from otherwise normal thyroid tissue. Prognosis is directly related to tumor size and a “good prognosis is associated with tumors less than 1.5 cm (1/2 inch) in size. This cancer has a high cure rate with ten year survival rates for all patients with papillary thyroid cancer estimated at 80-90%. Cervical metastasis (spread to lymph nodes in the neck) are present in 50% of small tumors and in over 75% of the larger thyroid cancers. The presence of lymph node metastasis in these cervical areas causes a higher recurrence rate but not a higher mortality rate. Distant metastasis (spread) is uncommon, but when it does occur the lung and bone are the most common sites. Tumors that invade or extend beyond the thyroid capsule have a worsened prognosis because of a high local recurrence rate. Surgery is the treatment for papillary cancer, which sometimes spreads to nearby lymph nodes. Nodules smaller than three quarters of an inch across are removed along with the thyroid tissue immediately surrounding them, although some experts recommend removing the entire thyroid gland. Surgery almost always cures these small cancers.
Since papillary cancer may respond to thyroid-stimulating hormone, thyroid hormone is taken in doses large enough to suppress secretion of thyroid-stimulating hormone and help prevent a recurrence. If a nodule is larger, most or all of the thyroid gland is usually removed, and radioactive iodine is often given in expectation that any remaining thyroid tissue or cancer that has spread away from the thyroid will take it up and be destroyed. Another dose of radioactive iodine may be needed to make sure the entire cancer has been destroyed. Papillary cancer is almost always cured.
Considerable controversy exits when discussing the management of well differentiated thyroid carcinomas (papillary and even follicular as described below). Some experts contend than if these tumors are small and not invading other tissues (the usual case) then simply removing the lobe of the thyroid which harbors the tumor (and the small central portion called the isthmus) will provide as good a chance of cure as removing the entire thyroid. These proponents of conservative surgical therapy relate the low rate of clinical tumor recurrence (5-20%) despite the fact that small amounts of tumor cells can be found in up to 88% of the opposite lobe thyroid tissues. They also cite studies showing an increased risk of hypoparathyroidism and recurrent laryngeal nerve injury in patients undergoing total thyroidectomy (since there is an operation on both sides of the neck). Proponents of total thyroidectomy (more aggressive surgery) cite several large studies that show that in experienced hands the incidence of recurrent nerve injury and permanent hypoparathyroidism are quite low (about 2%). More importantly, these studies show that patients with total thyroidectomy followed by radioiodine therapy and thyroid suppression, have a significantly lower recurrence rate and lower mortality when tumors are greater than 1.5cm. One must remember that it is also desirable to reduce the amount of normal gland tissue that will take up radioiodine.
Based on the these studies and the above natural history and epidemiology of papillary carcinoma, the following is a typical plan: Papillary carcinomas that are well circumscribed, isolated, and less than 1cm in a young patient (20-40) without a history of radiation exposure may be treated with hemithyroidectomy and isthmusthectomy. All others should probably be treated with total thyroidectomy and removal of any enlarged lymph nodes in the central or lateral neck areas. Thyroid cells are unique in that they have the cellular mechanism to absorb iodine to synthesize thyroid hormone. No other cell in the body can absorb or concentrate iodine. This uptake is taken advantage of in radioactive iodine treatments for thyroid cancer. Papillary cancer cells absorb iodine and therefore they can be targeted for death by giving the toxic isotope (I-131). Once again, not everybody with papillary thyroid cancer needs this therapy, but those with larger tumors, spread to lymph nodes or other areas, tumors which appear aggressive microscopically, and older patients may benefit from this therapy. This is an extremely effective type of “chemotherapy” will little or no potential adverse reactions (no hair loss, nausea, weight loss, etc.). However, the decision to use RAI should be made on an individual patient basis. Uptake is enhanced by high TSH levels; thus patients should be off of thyroid replacement and on a low iodine diet for at least one to two weeks prior to therapy. It is usually given 6 weeks post surgery (this is variable) can be repeated every 6 months if necessary (within certain dose limits).
Regardless of whether a patient has just one thyroid lobe and the isthmus removed, or the entire thyroid gland removed, most experts agree they should be placed on thyroid hormone for the rest of their lives. This is to replace the hormone in those who have nothyroid left, and to suppress further growth of the gland in those with some tissue left in the neck. There is good evidence that papillary carcinoma responds to thyroid stimulating hormone (TSH) secreted by the pituitary, therefore, exogenous thyroid hormone is given which results in decreased TSH levels and a lower impetus for any remaining cancer cells to grow. Recurrence and mortality rates have been shown to be lower in patients receiving suppression.
In addition to the usual cancer follow up, patients should receive a yearly chest x-ray as well as thyroglobulin levels Thyroglobulin is not useful as a screen for initial diagnosis of thyroid cancer but is quite useful in follow up of well differentiated carcinoma (if a total thyroidectomy has been performed). A high serum thyroglobulin level that had previously been low following total thyroidectomy especially if gradually increased with TSH stimulation is virtually indicative of recurrence. A value of greater than 10 ng/ml is often associated with recurrence even if an iodine scan is negative.
Surgery is usually the first line of treatment for thyroid cancer. Usually the whole thyroid gland (total thyroidectomy) will need to be removed, though sometimes only one lobe has to be removed; it depends on various factors such as your age, the size of the lump and results of the tests. The parathyroid glands may or may not be removed. After a thyroidectomy, patient need to take thyroxine tablets as prescribed for the rest of his/herlife; regular blood tests will be needed to check that patient thyroid hormone levels are within normal limits, and that the TSH level is suppressed. Eventually patient should only need a blood test once or twice a year.
Following surgery patient will need to have his hormone levels monitored
After thyroid surgery, GP will need to monitor patient thyroid medication and geblood tests to check hormone levels. When patient are at home after surgery,patient contact GP or treatment centre if:
- he feel extremely tired
- he have feelings of pins and needles in hands, feet or face
- he have palpitations
- he feel shaky
- he become very overactive, or
- he generally feel very unwell.
This may mean patient need to have thyroxine or calcium levels checked and patient medication dose increased or decreased, as the case may be. Once body has settled patient will be able to lead a normal life but will need to continue to take the thyroxine tablets for the rest of life and to have thyroid levels checked regularly. It will be particularly important to have thyroid hormones (TSH) checked if patient become pregnant, as he may need to increase her dose of thyroxine (levothyroxine). Patient will probably also need to have radioactive iodine treatment Most people need to have radioactive iodine treatment after surgery to destroy any remaining thyroid or cancer cells. Doctor will tell if this is the case. Radioactive iodine treatment is painless – it means taking either one or two capsule-type tablets, or as a liquid, in a single dose. Patient should not feel sick or lose any hair or have any other side effects with the usual dose required. It is a low dose of radiation but, for the safety of others, for the first 2–4 days a person needs to come into hospital and reduce their social contact. If patient need this treatment he will be informed by specialist consultant and given an information booklet before start the treatment.
Thyroid surgery is used to treat people with thyroid problems such as thyroid cancer, thyroid nodules and hyperthyroidism. The thyroid gland is the butterfly-shaped gland that can be seen on the neck. The thyroid gland produces thyroid hormones responsible for metabolism in the body. Once a person is diagnosed of thyroid cancer, thyroid nodules or hyperthyroidism, common treatment would be thyroid surgery especially if the disease is already severe. During the surgery, an incision is made in the skin. To expose the gland, the muscles and tissues are pulled aside. Below are other reasons why an individual undergo thyroid surgery:
- A fluid filled nodule reoccurs after being drained once or twice.
Medullary thyroid cancer is one of the types of thyroid cancer. This type of thyroid cancer is more common in women than in men. Medullary thyroid cancer usually originates in the upper central lobe of the thyroid. During the early stage of medullary thyroid cancer, the cancer cells spread to the lymph nodes. If left untreated, it may develop and spread to other distant organs in the body such as the brain, bone and liver. Medullary thyroid cancer also occurs in four clinical settings that are associated to other endocrine tumors.
Medullary Thyroid Cancer Symptoms
Symptoms of medullary thyroid cancer vary. It depends on the stage or how far the cancer cells have already spread in the body. Just like any type of thyroid cancer, it does not often show any symptoms. However as the cancer cells spread and grow, an individual may feel pain in the throat or neck, hoarseness or difficulty speaking in a normal voice and difficulty in swallowing or breathing. An individual may also notice that there is a lump or a nodule on the front of the neck. On the other hand, these symptoms may not be caused by medullary thyroid cancer at all. These symptoms may also be caused by other infections or goiter. If and when an individual feels any of these symptoms, it is best to go and see a doctor. Only a doctor can diagnose the cause of these symptoms and provide proper treatment.