What causes thyroid nodules?

Thyroid nodules are a common clinical disease with a very high incidence rate. Many people with thyroid nodules do not know the cause. There are many causes of thyroid nodules, and genetic factors are generally not ruled out, and they may also have some relationship with iodine.

1. Genetic factors: Genetic factors are also one of the four major factors that lead to the onset of thyroid nodules. There are many molecular abnormalities in thyroid nodules and tumors, which may be related to the occurrence or progression of tumors. Existing studies have shown that a variety of different candidate genes are involved in the pathogenesis of thyroid nodules, especially thyroid tumors.

2. Influence of iodine in the environment: Specific environmental factors (iodine deficiency) affect both the genotype and phenotype of thyroid nodules, and play a vital role in promoting the occurrence of thyroid cancer. It has been a consensus 200 years ago that severe iodine deficiency can cause endemic goiter. A recent study evaluating the relationship between iodine deficiency and the incidence of thyroid nodules in two regions of Denmark showed that 30% of patients in both regions with mild and moderate iodine deficiency had thyroid nodules detected by B-ultrasound. However, in regions with moderate iodine deficiency, thyroid nodules were larger and easier to feel during physical examinations.

3. Radiation exposure: History of exposure to ionizing radiation is an important pathogenic factor of thyroid cancer. The incidence rate of cancer in individuals receiving low-dose radiation (800-1000 rads) is close to 50%. Those who have previously received head and neck radiotherapy for head and neck diseases such as tonsils, thymus and facial diseases have a significantly increased risk of developing thyroid cancer in the future. The risk of thyroid cancer in patients with Hodgkin's disease who survive radiotherapy is eight times that of the general population.