Thyroid cancer is caused by what?

The exact cause of the current specific definitely hard, but epidemiological investigation, experimental tumor research and clinical observation, the incidence of thyroid cancer may be related to the following factors. (A) radiation injury mice with X-ray irradiation of the thyroid, to facilitate the occurrence of animal thyroid cancer. 131 Ⅰ can experiment proved that the thyroid cell metabolism changes in nuclear deformation, the synthetic thyroid hormone greatly reduced. On the one hand, shows that radiation caused by the abnormal thyroid cells split, leading to cancer; on the other hand, so that the destruction of the thyroid and endocrine-not produce a result, the thyroid stimulating hormone (TSH) secretion can trigger a large number of thyroid cancer cells. Clinically, a lot of facts show that the incidence of thyroid and radiation effects. It is particularly noted that the period in infants and young had enlarged thymus or lymph-like proliferation and acceptance of the mediastinum or neck radiation therapy for children especially prone to thyroid cancer, because children and adolescents in a strong cell proliferation, radiation An additional boost, its easy to trigger tumor formation. Adults and neck radiation therapy after the occurrence of thyroid cancer is rare. (B) iodine and TSH photo or excessive iodine deficiency can make the thyroid gland structure and function of change. Switzerland, such as endemic goiter prevalence area of thyroid cancer incidence rate than the 2 ‰ Berlin and other non-popular 20-fold higher. On the other hand, iodine is also easy to diet-induced thyroid cancer, Iceland and Japan are the highest in the photo iodine, the thyroid cancer rate than that found in other countries. This may be related to TSH thyroid stimulating proliferation of factors. Experiments have proved that long-term TSH to be able to stimulate the thyroid gland hyperplasia, and the formation of cancerous nodules. (C) other thyroid diseases are clinically thyroid cancer, chronic thyroiditis, nodular goiter or toxic goiter occurrence of cancer reported, but the thyroid disease and thyroid cancer, the relationship certainly hard. With thyroid adenoma, for example, for the vast majority of thyroid follicular adenomas, only 2 to 5% of the papilloma; such as thyroid cancer from Adenoma shift, for the vast majority of follicular, and the actual More than half of the thyroid cancer for the first service-like cancer, thyroid adenoma speculated that the incidence of cancer is very small. (D) of the genetic factor of about 5 to 10% of medullary thyroid carcinoma has a clear family history, often associated with pheochromocytoma, and so on Run, type of cancer that may be related to the incidence of chromosomal genetic factors.