by Dr. Sunita Khatri
In a recent television episode, the famous Dr. Mehmet Oz stated that people undergoing more than five X-rays per year are four times more likely to develop thyroid cancer. He has therefore, advised people undergoing dental, chest or mammography screenings to wear a protective lead thyroid shield.
Thyroid cancer is an extremely rare form of cancer. At present, we are aware of only two conditions that can lead to this type of cancer. They are:
- A rare genetic condition
- Exposure to large doses of radiation
The word ‘cancer’ is a dreaded word, especially today, when the world has just witnessed a nuclear accident at Fukushima, Japan. Therefore, this episode with Dr. Oz has triggered a panic reaction across the country.
But is the fear justified?
It is true that more people are being diagnosed with thyroid cancer than ever before. But then, according to the latest statistics available with the American Cancer Society, one does not come across any increase in the mortality rate due to thyroid cancer. According to Dr. Otis W, Brawley from the American Cancer Society, this is primarily due to the advanced technology available to us today that we are able to detect even those cases which would have otherwise gone unnoticed, as they do not constitute a health threat.
His views have been seconded by various studies on this subject. A recent study by Davies L and Welch HG, from the Dartmouth College, examined the causes behind the increasing incidence of thyroid cancer in the U.S. between the period of 1973 and 2002. They found that the increased incidence was mainly because of increased detection of small papillary cancers and many subclinical cancers. The researchers blamed this increased incidence on ‘over-diagnosis’ because of advanced imaging and biopsy techniques.
Another study by Dr. Peter D. Inskip, in Sweden, also could not find any significant association between the risk of thyroid cancer and diagnostic radiography.
Dr. Oz has pointed out that the rate of thyroid cancer in women has doubled from the year 2000 to the year 2008. But, if it were due to exposure to radiations during mammography screening, then the incidence of thyroid cancer should have been the maximum in women above the age of fifty, as the women above fifty routinely undergo mammography. However, no such difference in the incidence rate has been seen.
Similarly, it is wrong to blame the exposure to X-rays during dental screening for the increased incidence of thyroid cancer. These days, dentists usually rely on panoramic radiographs which film faster while emitting less radiation.
Going by the results of the above studies, one can safely conclude that there is no reason to panic while undergoing routine procedures like dental, chest and mammography screenings. These procedures do more good than harm.
However, it is known that one of the reasons for thyroid cancer is exposure to radiations. So, even if the amount of radiation exposure is very small in the screening procedures, repeated such exposure may, at least in theory, lead to a cumulative effect and produce mutations leading to thyroid cancer. Therefore, in my opinion, people may wear protective lead shields while undergoing dental, chest or mammography procedures, instead of shying away from the procedures, in order to allay their apprehensions.
Dr. Sunita Khatri passed her M.B.B.S from Shivaji University, Kolhapur, India. After completing her internship at S.B.D. Hospital, Saharanpur, she worked at the “Railways Cancer Institute” Varanasi in the department of surgical oncology where she gained hands on experience in various cancer surgeries. She has assisted in surgeries like mastectomies for breast cancer, abdomino-perineal resections for rectal cancers, commando surgeries for oral cancers, gastrectomy for stomach cancer, etc., besides routine operations like gastrostomy, ileostomy, etc. She has written multiple articles on various types of cancers and their treatment. She is a keen follower of the latest researches and development in the field of cancer and likes to share the same with her readers through her articles.
Currently, she is busy with her own private practice in New Delhi, besides writing health- related articles and blogs for various reputed medical sites on the net.