Clinical Thyroidology® for the Public
Summaries for the Public from recent articles in Clinical Thyroidology
Table of Contents | PDF File for Saving and Printing
THYROID CANCER
Do CT scans increase the risk of thyroid cancer?
BACKGROUND
Doctors often use computerized tomography (CT) scans to help find problems inside the body. CT scans are helpful, but they give off radiation, which could potentially damage cells and lead to cancer. In the past, studies have suggested that CT scans may cause thousands of new cancers in the future. The number of CT scans people get has increased over time and so has the concern about their safety.
The thyroid gland is sensitive to radiation and many CT scans include imaging the neck where the thyroid gland is located. In this study, doctors wanted to find out if more CT scans mean more risk of thyroid cancer, especially in children and adults who get scans of the head, neck, or chest.
THE FULL ARTICLE TITLE
Smith-Bindman R et al. Projected lifetime cancer risks from current computed tomography imaging. JAMA Intern Med 2025;185:710-719.
SUMMARY OF THE STUDY
This study looked at over 84 million CT scans done in the U.S. in 2023. It used a large database to figure out how many cancers might happen in the future from radiation during those scans. The researchers paid close attention to how much radiation different body parts received.
They found that about 7,000 future thyroid cancers could be caused by CT scan radiation. CT scans of the head, neck, chest, and cervical spine were the biggest contributors. Children were especially at risk. In fact, thyroid cancer was the most common cancer expected in kids after CT scans. Women were more likely than men to develop thyroid or lung cancer from CT scan radiation.
WHAT ARE THE IMPLICATIONS OF THIS STUDY?
The study shows that CT scans—especially of the head, neck, and chest—can raise the chance of getting thyroid cancer, especially in children and women. Doctors should be careful about how often CT scans are used and should only order them when truly necessary. This is important for patients because if you’ve had a lot of CT scans, especially in the head or neck area, it might raise your risk for thyroid cancer later in life. Patients should tell their doctors about any past radiation exposure when discussing thyroid issues or nodules.
— Maria Brito, MD, ECNU
ATA RESOURCES
Thyroid Cancer (Papillary and Follicular): https://www.thyroid.org/thyroid-cancer/
ABBREVIATIONS & DEFINITIONS
Computerized Tomography (CT) scan: A test that uses X-rays to make detailed pictures inside the body.
Radiation: A form of energy that can come from X-rays; too much can damage cells.
Papillary thyroid cancer: the most common type of thyroid cancer. There are 4 variants of papillary thyroid cancer: classic, follicular, tall-cell and noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP).
AMERICAN THYROID ASSOCIATION® , ATA® , THYROID® , CLINICAL THYROIDOLOGY® , and the distinctive circular logo are registered in the U.S. Patent and Trademark Office as trademarks of the American Thyroid Association® , Inc.