Prostate cancer develops when mutant cells in your prostate grow out of control. Experts don’t know what starts it. But they do know that the male sex hormones called androgens fuel it.
Men getting ADT may take medicines that stop their body from making or reacting to androgens. Sometimes it involves surgically removing their testicles, where most androgen is made.
With ADT, prostate cancer cells don’t grow as fast, if at all.
Unfortunately, ADT doesn’t usually work long-term. Prostate cancer cells eventually find a way to make their own androgen.
For some men, this can happen within months. For others, it can take years. It all depends on your genes, say researchers at Cleveland Clinic.
“Men with a certain variant of a specific gene are more likely to have prostate cancer recur sooner,” says Nima Sharifi, MD, a medical oncologist at Cleveland Clinic.
Dr. Sharifi and other researchers at Cleveland Clinic and Mayo Clinic studied 443 men with advanced prostate cancer. All of them had been treated with ADT.
Some of the men had “normal” HSD3B1 genes — two copies, one from each parent. A second group had a variant of the gene, but from only one parent. A third group had the variant gene from both parents.
ADT didn’t work as well in men who had the variant gene from both parents. Their prostate cancer began growing again after a median of 2.5 years.
In men who had the variant from one parent, prostate cancer held off for a median of 4.1 years. And in men who had the normal gene from both parents, prostate cancer held off for a median of 6.6 years.
Most men don’t know if they have normal or variant HSD3B1 genes. There isn’t a simple blood test to show it, although you can find out through a full genetic test.
“According to the 1000 Genomes project, about half of U.S. men and women have the variant gene — from either or both parents,” Dr. Sharifi says.
A blood test for the variant isn’t yet available because researchers don’t know if changing treatment for prostate cancer patients with the variant would improve their outcomes. More research is needed, Dr. Sharifi says.
Cleveland Clinic researchers are now doing just that — studying if alternative hormone therapies work better than ADT in men with the variant gene.
Time will tell, but Dr. Sharifi suspects that more aggressive treatment may work better in men that don’t respond well to ADT.
“Some day soon, doctors will rely on genetic testing to determine the best treatments for patients,” Dr. Sharifi says. “We will no longer treat prostate cancer according to one standard of care.”