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Subscribe to RSSFor men diagnosed with prostate cancer, the decision about how to treat it -- or even whether to treat it -- can be agonizing. Surgery, radiation, or some combination of both may lead to miserable side effects such incontinence, impotence and rectal damage. Doctors usually can’t predict whether a man will suffer all or none of those side effects. While some risk factors are well-known -- including age, diabetes and poor cardiovascular health -- whether a man suffers harsh side-effects is often chalked up to random luck.
So what if it were possible to know before treatment which men might be more likely to suffer complications?
New research, published Thursday in the International Journal of Radiation Oncology, discovered a set of genetic markers that appear to indicate a significantly greater risk of collateral damage from radiation treatment for prostate cancer. Knowing a man’s susceptibility to fallout from radiation may steer a doctor toward surgery instead of other potentially damaging therapy.
“More often than not, it’s not clear-cut which way to go,” explained Barry Rosenstein, professor of radiation oncology at Mt. Sinai School of Medicine in New York City. “If you see a surgeon, he’s likely to say surgery is best. If you see a radiation oncologist he’ll say oncology.”
Determining what type of treatment a man should receive is only part of the dilemma of prostate cancer. The debate whether to even test for it is ongoing. This early-stage study represents a big step toward doctors and their patients making that decision.
The researchers started with a pool of 841 men treated with radiation for prostate cancer. Patients were assessed every three to six months for signs of sexual dysfunction for up to five years. The number of men studied was eventually winnowed down to 260 patients with erectile dysfunction and 205 controls.
The scientists then performed DNA analyses on the men, looking for genetic variations called single nucleotide polymorphisms, or SNPs (pronounced snips), slight differences in the “spelling” of our DNA. After sifting through hundreds of thousands of SNPs, they settled on 12 suspect genetic variations.
It turned out that when the SNPs were combined to create a score that could be used to measure individual risk of treatment complications, having just one of the 12 SNPs more than doubled the risk. The more of the 12 a man had, the greater his chances of radiation therapy complications.
“It is cumulative,” Rosenstein explained. “If a man has five or six, it increases his chances quite a bit.”
The research is still in the early stages, so doctors aren’t likely to be using the genetic markers to determine treatment any time soon. “This is still not nearly good enough, yet” he said.
But he’s part of an international consortium that is trying to make that very scenario a practical reality. The next step, he said, is for group members to validate the predictive power of the markers his team found.
If they can, then doctors really will be “able to assign patients to treatments and see if we maintain the same level of control of cancer and lower the incidence of complications,” he said. “And if we can do that, then there’ll be enough confidence to put it into use in the clinic.”
Even better, he suggested, it may one day be possible to use drugs to target the SNiPs, or the biological processes they influence, as a way to prevent damage from therapy.
That hope is evident to other researchers, such as Dr. Ithaar Derweesh, a urologic oncologist and associate professor of surgery at the University of California San Diego Moores Cancer Center.
"This is a study that in certain ways is groundbreaking and also elegantly performed," Derweesh said.
While Derweesh agreed with Rosenstein that such a technique will take time to validate, and be used to steer patients toward a particular therapy -- something he called the "holy grail" -- he suggested that in the nearer term, such markers might be used as a trigger to pre-emptively begin erectile rehabilitation or to take measures that might lessen the potential damage.
This kind of work is important not just for prostate cancer, but all cancers. While there has been greater success in treating cancer, survivors may live many years with side effects after treatment. If Rosenstein’s hopes are fulfilled, it may one day be possible to prevent some of the damage before it’s done, and still effectively treat the cancer.
Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young Ph.D., of "The Chemistry Between Us: Love, Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com), now on sale.
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NBC- A quote in this article appears to be incorrect. When Rosenstein is quoted as saying “If you see a surgeon, he’s likely to say surgery is best. If you see a radiation oncologist he’ll say oncology.", surely the actual quote has the last word as "radiation" rather than "oncology," right? both surgery and radiation fall within the realm of oncology when used to treat cancer.
The type of prostate cancer I had would NOT respond to radiation, it had to be cut out.
Knowing the DNA would have made NO difference, it had to come out.
Take your zinc pill everyday....your doc can't legally recommend you take zinc (they know about the study and most male docs take zinc themselves) but it works..I have known several men in my life that Zinc has kept from the knife.
"New research, published Thursday in the International Journal of Radiation Oncology, discovered a set of genetic markers that appear to indicate a significantly greater risk of collateral damage from radiation treatment for prostate cancer."
This research appears to be the result of recent changes in the screening/treatment recommendations for prostate cancer, as many studies are showing that informed decision making often has patients opting out of treatment given the risks and potential side effects, including impotence.
The other issue is that many males have prostate cancer throughout their life and don't experience adverse effects. IN other words, the risks outweigh the potential benefits and even those benefits are not guaranteed. In the end, men need to do their own research and then discuss with their doctor.
I am right in the middle of that controversy and local physicians are far less than helpful. I had a high PSA about a year ago and several followups also showed a fairly high velocity. But my primary physician advised "the daVinci" and the local urologist told lurid tales of what it is like to die from terminal prostate cancer. Neither would answer questions, especially the big one: "Why had no major study found any benefit in longevity overall or longevity associated with prostate cancer?" The urologist threw his clipboard across the room and walked out. Now my primary thinks I am suicidal.
But I have an ace in the hole. My wife is a PhD gerontologist. And I have access to competent SCIENTIFIC medicine. The bottom line is that 19 out of 20 men who have careful PSA and DRE monitoring, biopsies, and surgery/radiation/chemo/horone therapy have it completely unnecessarily. For those 19 out of 20 men, the issue is all risk and zero benefit. The problem is that there is no easy cheap way to tell whether a person has the form of prostate cancer that will kill you or the one that will let something else kill you first. A biopsy operates on the surrogate endpoint "presumption" that if the cancer is widespread in the prostate then it is "probably" the lethal variety. But several recent studies have found that in many prostates the lethal type of cells are found only along the needle tracks from the biopsy and nowhere else in the prostate.
So I have decided to do exactly nothing. "Nothing" is very good at preserving quality of life since it entails zero erectile dysfunction, zero urological problems, and zero anal retention issues. If I develop further symptoms, I will pursue it further at that time. Most people would not bet in a situation where the odds were 19-to-1 against you. Physicians are very dishonest about the risks involved (they are much higher and more serious that they suggest) and about the necessity (19 out of 20 prostate cancers need ZERO treatment ever) and about the best course to follow. It boils down to the simple fact that every so-called "prostate cancer cure" puts about $300,000 in the pockets of the medical establishment. And you can imagine the effect on a urologist's revenue stream if the number of cases were diminished by 95%.
If you get in a similar situation, do your own research. Make sure that both your primary and urologist give you matching (NOT CONFLICTING) information, and then make your decision based on the best information you can get, not an induced paranoia about cancer.
Thought Obamas death panel already decided prostate cancer didn't need to be treated?
Two yrs postop for prostate cancer. The only thing is my erection is about 2 inches smaller now but I am still able to sexually function. No sperm on ejaculation but whowants more kids at 72?
The illegals. Can use them for anchor babies.
The MDs have a favorite line--most men with die with, but not of, prostate cancer. Only problem is that none of the tests or studies clearly tel us who is a "with" or who is an "of." I was diagnosed 5 years ago. Opted for the gold standard in the game, a radical prostatectomy. For a 68 year old man, my erection is just fine. No side effects of any kind.
its worked out okay, I had a 10 inch pump inserted like a DD breast job, and now just click the pump and can get a 21 year old girl at age 70....
If you opt for surgery instead of radiation, the risk is getting your pudendal nerve cut by the surgeon... that's not exactly predictable by DNA or a safer (less susceptible to luck) option than radiation.
My husband is 81, had the radiation and now has damage to his bowel. Horiffic bleeding that never healed caused anemia, to which he had to get a blood transfusion, iron and a 5 day hospital stay. Constant weakness, lethargy and nausea has plagued him since the treatment. He says now he would NOT have had it done since it would have taken up to 10 years for the cancer to kill him anyway. What REALLY makes me mad is the doctors never told him how bad these side effects could get as a result of the treatment!
I had major phostate problems without having cancer. I went the microwave way on treatment. I feel blessed that it solved my problems. At this old age, I'll take the lack of sex drives I had afterwards. If you listen behind my closed rest room door. You will hear my voice saying "thank you!! thank you!! while I'm taking a leak. We never appreciate each part of our body, until something breaks inside. When we are lucky on having it repaired, the words come out.(Thank you!!! Thank you!!!
I wish you all on full recovery.