Thyroid Cancer – The Four Types
Thyroid cancer (cancer of the thyroid gland) comes in four types: papillary, follicular, medullary and anaplastic. Papillary and medullary are slow-growing and occasionally return, but respond well to therapy in patients under middle age.
Medullary also responds well to therapy, if it has not already spread. Anaplastic developes rapidly and responds badly to therapy. The extent of these types of cancer is not uniform throughout the world, but is roughly: 78% for papillary; 17% for follicular; 4% for medullary and 1% for anaplastic.
Usually, the first symptom of a problem is the growth of a nodule or nodules in the neck in close proximity to the thyroid gland. However, only 5% of these are malignant. Sometimes an early warning sign is discomfort or even pain; sometimes, the lymph nodes swell, the voice alters or there is hypo- or hyper- thyroidism.
Diagnosis usually takes place after a nodule is discovered during a (routine) physical examination. The patient is then referred to an endocrinologist or a thyroidologist, who will arrange an ultrasound test or a biopsy. Using a thin needle enough cells can be taken to perform an accurate test on the precise state of the thyroid and whether the nodules are cancerous.
Papillary thyroid cancer more frequently occurs in women and often in the 30-40 year old age group and is frequently characterized by bulging eyes. If the growth is less than 1cm in size a partial thyroidectomy or hemithyroidectomy would probably be recommended.
Greater than 1cm and a full thyroidectomy is favoured. Some surgeons would rather a full thyroidectomy anyway because the cancer cannot come back then.
Follicular thyroid cancer is more common in women over 50 years of age. Therapy is most often full thyroidectomy as the threat of recurrence of this aggressive form is quite big for partial surgery.
Medullary thyroid cancer (MTC) starts in the cells that produce the hormone calcitonin. Increased degrees of calcitonin in the blood are a realistic indication of MTC, although these elevated levels of calcitonin are probably not harmful in themselves.
Changes in the DNA concerned in cell growth and development are responsible for nearly all cases of hereditary or familial medullary thyroid carcinoma. Hereditary medullary thyroid cancer is inherited as a 50/50 likelihood from every affected parent. DNA analysis makes it possible to identify children who carry the mutant gene.
Surgical removal of the thyroid in children who carry the mutant gene is effective if the whole thyroid gland is removed at an early age, before there is a spread of the tumor. Hereditary MTC accounts for around 25% of all cases of MTC. The other 75% of cases are known as sporadic MTC and normally occur in older patients.
Frequently the disease is well advanced in these cases as there has been no screening as in hereditary MTC. The first sign is frequently diarhoea. The likelihood of surviving MTC seem to be related to the rate at which the patient?s post operative calcitonin levels double.
Anaplastic thyroid cancer is extremely aggressive and likelihood of survival are virtually nil. It is resilient to all known cancer treatments and invades nearby tissue rapidly.
Owen Jones, the writer of this article, writes on quite a few topics, but is now involved with the stages of ovarian cancer. If you want to know more, please visit our web site at Signs and Symptoms of Ovarian Cancer