When I had thyroid cancer 1981 (30 years - yippee), there were about 10,000 cases each year in the US. Now there are over 30,000 cases each year. (To compare there are about 200,000 cases of breast cancer in the US each year.) The reason for the increase not really known but there are several theories - increased exposure to radiation and chemicals and better detection and diagnosis.
There are several types of thyroid cancer. Papillary, follicular, medullary, and anaplastic are the big ones. Papillary and follicular are the most common. Anaplastic is the most deadly - any anaplastic diagnosis is automatically stage IV. I had both papillary and follicular.
The standard treatment for thyroid cancer is to surgically remove the bulk of the tumor and most of the thyroid. It is impossible to surgically remove the entire thyroid because of the neighborhood it is in - right next to those important things like jugular, esophagus, spinal column, etc - so then they usually dissolve the remaining portion of your thyroid with radioactive iodine. Your thyroid tissue absorbs iodine and the radiation will kill it off. Chemotherapy is usually not needed unless it has spread elsewhere in your body.
Standard follow up for treatment is replacement thyroid hormone for life, neck ultrasounds every five years, and sometimes full body scans with radioactive iodine to look for metastases. Back when I was diagnosed, there were no ultrasounds so I just went to an endocrinologist for about 10-15 years until she retired. Then I just went to my regular doctor. Now I go to an endocrinologist and my primary care and my oncologist (and a million other doctors).
I hope I have educated everyone about this growing cancer. You will notice I didn't link to any websites because I know all this because it has been my life. But here are some references where you can check and see if I messed up.