Answer to Question #13997 Submitted to "Ask the Experts"

My five-year-old son woke up one morning with severe  pain in his left hip and couldn't walk. We took him to the hospital where they did blood tests and took x rays of his hip. They did one "frog leg" and two anteroposterior (AP) x rays for a total of three images. When performing the x rays they only shielded his gonads for the frog-leg view. The technologist told me the dose my son received was 0.4 miiligray (mGy) and that it was a very low dose. I asked the doctor before the x ray about possible risks. The doctor assured me that the radiation dose is extremely low and he said he wouldn't think twice about having it done to his children. There is a lot of scary information on the internet about radiation exposure, so I am worried. Is there any risk of testicular cancer or issues with fertility from this exposure?

I understand your worry especially given the age of your son, and trying to interpret possible risks using information, and misinformation from the internet can lead to some scary conclusions. I am very happy to hear that your son's symptoms have resolved themselves. I had similar concerns when my daughter wasn't one day old when she received her first series of x rays. First off, there is no reason for concern regarding fertility issues at any age from diagnostic x ray exposures of the type your son received. The threshold for temporary or permanent fertility effects are much, much higher than what could be received from a diagnostic x ray, so there is no need to worry about that possibility.

Now let's discuss your other concern—the issue of cancer, and specifically testicular cancer. Statistics published by the American Cancer Society show that testicular cancer is not common and occurs in about 1 of every 250 males. The average age at which man will be diagnosed with testicular cancer is 33 and 6% can occur in children and teens.

The probability that radiation can cause testicular cancer has been studied. Several studies have been conducted for men exposed to radiation to determine whether there is a causal link to testicular cancer. One study did show a slight increase in risk in males between 0-10 years old who were exposed to x rays, but the dose levels they considered were 100 times higher than the exposure your son most likely received. An additional study also assessed the risk of testicular cancer and found that plain x rays are unlikely to increase testicular cancer risk. I could go on, but the evidence is clear; testicular cancer from radiation levels delivered by three diagnostic x rays is very unlikely, especially when the testis are only indirectly exposed.

In summary, we cannot state that the risk to your son from the x ray radiation exposure is zero; however, there is little evidence to suggest your son will experience any increase in cancer risk from the x rays compared to the risk that any male already faces in life for testicular cancer such as that from genetic and environmental sources. I hope my explanation has provided you with some measure of assurance. One thing to always keep in mind is that the benefit of medical imaging to diagnose possible health issues is always much greater than the risk that may be inherent from the radiation exposure, even when the x rays do not show any problems. Peace of mind should never be underrated especially when it involves our children.

Christopher B. Martel, PhD, DABHP, FHPS