January 19, 2012 | by City of Hope Staff
The ACS reports that thyroid cancer has “significantly increased among men and women of every racial/ethnic background” except for Native-American men. No one is entirely sure why, although City of Hope thyroid specialist John H. Yim, M.D., associate professor in the Division of Surgical Oncology, is exploring the issue.
The thyroid is a gland located in the neck that helps regulate the body’s metabolism, makes proteins and controls how sensitive the body is to other hormones, he explains. Thyroid cancer, like other problems such as hyperthyroidism, is more common among women than men. Exposure to ionizing radiation (such as X-rays, ultraviolet radiation or nuclear reactor meltdown fallout, as seen at plants in Ukraine and Japan) are strong risk factors for thyroid cancer. Genetics also factor into risk.
The rate of thyroid cancer appears to be increasing around the world. City of Hope conducted a study that will be presented at the Academic Surgical Congress meeting in February that shows that the rate of thyroid cancer is increasing more rapidly in South Korea than the United States, but among Korean-Americans in Southern California is increasing at the same rate as the rest of the U.S.
We think that increased surveillance with ultrasound is definitely a factor. In South Korea, there may be greater ultrasound surveillance with biopsies of very small thyroid nodules, which results in finding more thyroid cancers.
However, we are not only seeing an increase in small thyroid cancers (which are the ones identified by ultrasound that weren’t identified before), but also in larger thyroid cancers. If the increase was solely due to ultrasound diagnosis, these larger ones shouldn’t have shown a similar increase in incidence.
Fortunately for thyroid cancer, the prognosis is excellent, with a very low rate of cancer death. There is no question that finding thyroid cancers earlier results in less chance of spread to lymph nodes and distant metastases.
The ACS estimates that 56,460 Americans will be diagnosed with thyroid cancer this year, but only 1,780 will die from the disease. The 5-year survival rate for patients with localized tumors is 99.7 percent.