Genetic markers found by New York City researchers that could flag patients most at risk of erectile dysfunction after radiotherapy for prostate cancer may help doctors pick the best treatment for their patients.
Having prostate cancer causes enough anxiety on its own, without the worry that radiotherapy, such as brachytherapy (internal radiotherapy using seed implants) and external beam radiation (though effective) can leave up to 85% of men with ongoing sexual problems. Though many recover after time and treatment, the sexual problems can still have a major impact on quality of life and relationships.
The researchers screened the genomes of men treated using radiotherapy in what's known as a genome-wide association study, and found 12 tiny, single-letter changes (single nucleotide polymorphisms or SNPs) that they linked with the risk of erectile dysfunction up to four years after treatment. The more changes, the higher the risk. The results were published in the International Journal of Radiation Oncology • Biology • Physics.
"Our study confirms that specific markers make certain patients more susceptible to this side effect," said Barry Rosenstein of Mount Sinai School of Medicine. Thankfully, current treatments for prostate cancer offer excellent rates of long-term survival, so patients and their physicians have a choice about which treatment path to take."
As the researchers say, these results do need validating in other groups of patients, but could evolve into a useful tool to help improve quality of life or as pointers toward developing new treatments. The team is also looking into other side effects of radiotherapy--rectal discomfort and urinary problems--both of which can have a major impact on cancer survivors.