In the first study of its kind, a research team led by Mount Sinai School of Medicine and Albert Einstein College of Medicine of Yeshiva University discovered 12 genetic markers associated with the development of erectile dysfunction (ED) in prostate cancer patients who were treated with radiation.
The findings, to be published online September 27, 2012, in advance of the October 1, 2012 print issue in the International Journal of Radiation Oncology• Biology• Physics, the official scientific journal of the American Society for Radiation Oncology, are an important step towards helping clinicians determine the best course of treatment for prostate cancer patients and may lead to the development of therapies that alleviate side effects.
The main treatments for prostate cancer – surgery, brachytherapy (seed implants) and external beam radiation therapy – are all very effective at curing prostate cancer. Unfortunately, each treatment places patients at risk for ED. According to the National Cancer Institute, the prevalence of erectile dysfunction following external beam radiation for prostate cancer ranges from 65 percent to 85 percent. The Prostate Cancer Foundation estimates prevalence of ED following seed therapy at 25 to 50 percent. Many men will be able to regain their potency with time and treatments, but doctors would like to identify which men may be more likely to develop this side effect.
In the first large scale Genome-Wide Association Study to identify single nucleotide polymorphisms (SNPs) associated with susceptibility for the development of erectile dysfunction following radiotherapy for prostate cancer, researchers conducted a two-part study, first, to discover the candidate genetic markers of side effect risk, and second, to confirm which of those markers are replicated in a second group of patients. In the first group of prostate cancer patients, which included 132 men who developed erectile dysfunction after radiotherapy and 103 men similarly treated who did not develop erectile dysfunction, they found a set of genetic markers associated with erectile dysfunction. In the second part of the study, which examined 128 patients who developed erectile dysfunction after radiotherapy and 102 who did not, researchers confirmed that 12 SNPs were associated with erectile dysfunction.
"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," said Barry Rosenstein, PhD, Professor of Radiation Oncology, Mount Sinai School of Medicine. "However, the risk of developing erectile dysfunction after radiation treatment is highly variable, suggesting there may be a genetic component to determining that risk. Our study confirms that specific markers make certain patients more susceptible to this side effect."
Patients in the study cohort were given one of three treatments: internal radiotherapy, known as brachytherapy; brachytherapy plus external beam radiation; or external beam radiation alone. They were followed for an average length of nearly four years to determine level of sexual function after treatment.
Interestingly, the 12 SNPs identified in this study were located near genes that seem to be related to erectile function rather than related to radiation response. The researchers conclude that these SNPs may affect genes that sensitize a patient to developing erectile dysfunction when exposed to radiation during therapy.
"Prostate cancer screening and treatment are undergoing major shifts," said Harry Ostrer, MD, Professor of Pathology and Genetics at Albert Einstein College of Medicine and Director of Genetic and Genomic Testing at Montefiore Medical Center and co-principal investigator of the study. "This is part of our ongoing effort to identify men at highest risk for disease, identify the aggressive tumors that would be responsive to therapy, and to improve quality of life for men with indolent prostate cancers who might benefit from active surveillance, rather than therapy."
The authors indicate that examination of a large, independent cohort of similarly treated patients will be necessary to definitively determine which SNPs to include as part of a clinically useful predictive test to identify which men are at greatest risk for developing erectile dysfunction following prostate cancer radiotherapy. The researchers are also evaluating the impact of radiation treatment on urinary complications and proctitis, the inflammation of the rectum.
This study was supported by the American Cancer Society, United States Department of Defense, and the National Institutes of Health.
About The Mount Sinai Medical Center
The Mount Sinai Medical Center encompasses both The Mount Sinai Hospital and Mount Sinai School of Medicine. Established in 1968, Mount Sinai School of Medicine is one of the leading medical schools in the United States. The Medical School is noted for innovation in education, biomedical research, clinical care delivery, and local and global community service. It has more than 3,400 faculty in 32 departments and 14 research institutes, and ranks among the top 20 medical schools both in National Institutes of Health (NIH) funding and by U.S. News & World Report.
The Mount Sinai Hospital, founded in 1852, is a 1,171-bed tertiary- and quaternary-care teaching facility and one of the nation's oldest, largest and most-respected voluntary hospitals. In 2012, U.S. News & World Report ranked The Mount Sinai Hospital 14th on its elite Honor Roll of the nation's top hospitals based on reputation, safety, and other patient-care factors. Mount Sinai is one of 12 integrated academic medical centers whose medical school ranks among the top 20 in NIH funding and by U.S. News & World Report and whose hospital is on the U.S. News & World Report Honor Roll. Nearly 60,000 people were treated at Mount Sinai as inpatients last year, and approximately 560,000 outpatient visits took place.
For more information, visit http://www.mountsinai.org/.
Find Mount Sinai on:Facebook: http://www.facebook.com/mountsinainyc
Chances to treat childhood dementia
24.07.2017 | Julius-Maximilians-Universität Würzburg
World first: Massive thrombosis removed during early pregnancy
20.07.2017 | Universitätsspital Bern
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....
A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...
21.07.2017 | Event News
19.07.2017 | Event News
12.07.2017 | Event News
24.07.2017 | Power and Electrical Engineering
24.07.2017 | Materials Sciences
24.07.2017 | Materials Sciences