Do Steroids Cause Cancer?

by Cy Willson

The New Study

Everyone thinks that androgen abuse causes cancer, but does it? A new study gives us some insights.

Before he died of cancer in 1992, Lyle Alzado, the famous American football star, blamed his steroid use for his brain tumor. “Steroids cause cancer” became the mainstream narrative. But does androgen abuse really cause various forms of cancer?

While exogenous testosterone, especially in the form of testosterone replacement therapy (TRT) has largely been cleared of causing an increased risk of prostate cancer, whether other androgens may cause issues, especially when abused, isn’t known. A recent study evaluated a cohort of long-term androgen users to provide an answer (1).

The Study

Researchers evaluated a group of men who were kicked out of Danish fitness centers as part of an anti-doping initiative. As part of this initiative, members suspected of using androgens were tested and those who were positive were booted. If they refused to submit to testing, they were booted anyway.

The researchers contacted a lot of these people (average age 27) and tracked them for around 11 years while comparing them to a control group of non-users.

When they compared the two groups and the incidence rate of all forms of cancer (except for non-melanoma skin cancer), it was effectively indistinguishable. In fact, none of the 1,189 androgen users developed prostate or breast cancer.

You might assume the case is closed and think that cancer isn’t a concern with androgens. However, the authors point out several limitations of this study. First, cancers such as prostate and breast cancer are rarely diagnosed in men under age 50. The follow-up period may still be too short to detect an increase in cases. Second, while androgen use can be presumed, it may not be the case that everyone in the study was abusing androgens considering the broad category of doping substances.

Interestingly however, the authors did find that in those individuals who did receive a diagnosis of some other form of cancer, androgen users had a substantially lower survival rate over 10 years post-diagnosis, versus controls. Of course, this could be confounded by many other variables, but it’s interesting.

Take-Home Point

Androgen users should take some comfort in the finding of no increase in cancer rates over an average period of 11 years. However, it’s still too early to rule out any increase in all forms of cancer because the median age of cancer diagnosis is in the mid-60s.

The substantially lower survival rate in androgen users is worrisome, but it’s too difficult to rule out confounders and attribute to androgen use alone. It’ll be interesting to see the results over a follow-up of another 20 years. Unfortunately, it’ll take that long to have a more definitive answer. For the time being, cardiovascular risks have the most substantiation. (Editor’s Note: Here’s how to help minimize those risks.)

Reference

1. Heerfordt IM, Windfeld-Mathiasen J, Dalhoff KP, Trærup Andersen J, Horwitz H. Excessive androgen exposure and risk of malignancies: A cohort study. Andrology. 2024 Apr 11. doi: 10.1111/andr.13648. Epub ahead of print. PMID: 38602128