In many countries around the world, thyroid cancer is growing faster than most other types of cancer. For example, in the United States, this type of oncology ranks first in terms of increasing incidence. Doctors are trying to figure out what is behind this “mysterious epidemic.”
The thyroid gland is located at the base of the neck and produces hormones that regulate heart rate, blood pressure, body temperature, and weight. Thyroid cancer occurs when cells in the gland begin to divide uncontrollably, forming a tumor that sometimes spreads to nearby tissues and other organs.
According to the SEER database, from 1980 to 2016, the number of cases in the United States almost tripled: in men - from 2.39 to 7.54 per 100,000, in women - from 6.15 to 21.28 per 100,000.
One reason for the increase in incidence is more accurate diagnosis. Since the 1980s, doctors have been actively using ultrasound and fine-needle biopsy to detect small tumors that were previously invisible to a routine examination. This has allowed the detection of small papillary tumors, which are rarely life-threatening but are now included in the statistics.
At the same time, researchers note that pre-diagnosis does not explain all the increase. In some middle-income countries without mass screening, an increase in incidence is also recorded. Not only small nodules are growing, but also more aggressive tumors that spread to other organs.
Risk factors include obesity, elevated thyroid-stimulating hormone (TSH), inflammation, and insulin resistance. People with a high BMI are 50% more likely to develop thyroid cancer. Other possible causes include exposure to household chemicals, pesticides, medical radiation from CT scans and X-rays, and the presence of certain trace elements in soil and water.
Thus, the increase in thyroid cancer is a multifactorial phenomenon where genetics, metabolism, nutrition, environment, and hormonal influences interact.
