Showing posts with label DRE. Show all posts
Showing posts with label DRE. Show all posts

Tuesday, 31 March 2009

The Man, the Gland, the Dilemmas

Article from Wall Street Journal

You've been getting annual blood tests to check for prostate cancer. But two big studies in the New England Journal of Medicine just found that screening for PSA -- prostate specific antigen -- doesn't save many lives. Should you keep checking it?

Your biopsy was negative for prostate cancer but your PSA keeps rising. Should you stop worrying -- or have another biopsy?

You've been diagnosed with early-stage prostate cancer. It's probably harmless, but it could turn lethal. Should you just watch it or treat it aggressively and run the risk of impotence or incontinence?

Prostate cancer poses some of the most vexing questions in medicine, and one out of every six men in the U.S. will confront them at some point in their lives. Today's Health Journal is the first of a two-part series that aims to provide some guidance. This article looks at new diagnostic techniques that may help to resolve some of these quandaries. Next week we'll examine the perplexing array of treatment options and weigh the pros and cons of each.


Should You Be Screened?

For all the uproar they created, the recent NEJM studies settled little in the long-running debate over whether prostate-cancer screening is worthwhile.

PSA testing revolutionized detection of the disease in the late 1980s. Before that, doctors relied on a digital-rectal exam, or DRE, and by the time tumors could be felt, some were fairly large. Now, about 90% of prostate cancers are found at an early and highly curable stage.

But PSA screening can flag tumors almost too early, leading to considerable unnecessary surgery or radiation. Most prostate cancers are so small and slow-growing that they don't need treatment. Of the 185,000 U.S. men diagnosed with the disease each year, an estimated 85% would likely die of something else long before their cancer caused problems.

On the other hand, some prostate cancers are aggressive, each year killing some 28,000 men in the U.S. -- and 288,000 worldwide -- who weren't treated in time. It's the second most deadly cancer in men, after lung cancer.

As of now, it's difficult to tell which patients have which kind of tumors in the early stages. Experts say many more men could safely opt for "watchful waiting" -- monitoring their cancers to see if they grow. But thousands of men each year opt to have their prostates removed surgically or treated with radiation to be on the safe side, and many live with urinary or erectile problems in the bargain.

"Right now we are treating people for anxiety, not cancer," says Faina Shtern, CEO of the AdMeTech Foundation, a nonprofit group that is lobbying Congress to increase federal funding for research into prostate imaging. "We do not know if they will benefit from treatment, but we know they will have complications," Dr. Shtern says.

Weighing all those factors, a U.S. government panel last year recommended that doctors stop screening men age 75 and over for prostate cancer, since the risk of treating it likely outweighed the benefits.

The recent NEJM studies seemed to extend that reasoning to younger men as well. One study of 77,000 North American men showed that regular PSA screening didn't save a significant number of lives over 10 years. A study of 182,000 European men showed a 20% reduction in deaths among those screened regularly. But in that study, 48 men had to be treated for every life saved.

Still, many cancer organizations issued statements defending PSA testing -- in the absence of something better -- and urging men to discuss it with their doctors.

Most doctors believe that men with a family history of prostate cancer should have annual PSA testing, along with African-American men, for whom the death rate from prostate cancer is twice as high as for whites. For others, "you probably don't have to get it tested every year," says Al Barqawi, a urologist at the University of Colorado Health Sciences Center. "If there's a change, then do it more often."


"Blind" Biopsies

A PSA level is cause for concern if it's higher than usual for the man's age or rising rapidly. If so, the next step is usually a biopsy. That's typically done in a urologist's office with an ultrasound probe and a spring-loaded needle gun inserted into the rectum, taking six to 12 samples at random.

The ultrasound can't see well into the prostate, so urologists are effectively sampling blindly. More than 1.2 million American men have such transrectal ultrasound, or TRUS, biopsies each year due to a suspicious PSA level. Less than 15% come back positive for cancer. But TRUS biopsies miss about 20% of cancers, so a negative biopsy isn't completely reassuring.

That's the situation Richard Edelman, president and chief executive of the Edelman public-relations firm, faced in 2007. His PSA had doubled over two years to four nanograms/milliliter, considered elevated for his age of 54. He also had three close relatives with prostate cancer. A standard TRUS biopsy was negative, but a few months later, his PSA had jumped to 7.5 ng/ml.

His doctor suspected a urinary-tract infection, one of several benign conditions that can increase the PSA level, and prescribed an antibiotic. But Mr. Edelman's PSA remained elevated, as did his anxiety.

To get more information, Mr. Edelman enrolled in a clinical trial at the National Cancer Institute, where doctors are hoping to improve tumor detection by scanning prostates with magnetic-resonance imaging. The MRI scans are then used to target biopsies at suspicious-looking areas. Mr. Edelman had a second biopsy, guided by MRI, which found cancer in two of 21 samples. "The value of the MRI was huge," he says.

Imaging of the prostate has lagged far behind imaging for breast cancer in women -- largely because the prostate is deep inside the pelvis and harder to access. "It's medieval and barbaric what we do to men without better imaging," says AdMeTech's Dr. Shtern, who helped advance the use of MRIs for breast cancer at the NCI in the 1990s. She notes that NCI today spends twice as much on research into breast cancer than prostate cancer research, even though prostate cancer is twice as prevalent. Mr. Edelman's firm is helping her group's efforts; as are some equipment manufacturers.

Researchers at NCI and several major medical centers are currently using several kinds of advanced MRIs to scan the prostate for abnormalities that could signal cancer. MRIs with contrast agents can highlight areas of new blood-vessel growth. Other techniques include MR spectroscopy, which looks for telltale chemical changes, and diffusion-weighted MRIs, which measure changes in water flow around cells. Clinical trials are underway to assess whether biopsies guided by such images are better than standard TRUS biopsies at finding cancers.

"None of these tests will absolutely differentiate benign from malignant. They're pointers to areas that should be further biopsied or followed," says Peter Choyke, the NCI's chief of molecular imaging.

MRIs often identify abnormalities that aren't cancerous. They also add $1,000 or more to the cost of a biopsy, which itself runs about $2,000. But Dr. Shtern argues that scanning before performing a biopsy could save money in the long run if it helps to reduce the $2 billion spent annually on standard biopsies that don't find cancer.

"It sounds good, but the burden of proof is on us to show that this makes a difference in detecting cancers," says Peter Pinto, director of the fellowship program at NCI's urologic oncology branch.


Has it Spread?

Once a biopsy confirms cancer, many major medical centers now use MRIs to help determine whether it has spread beyond the prostate and invaded the nearby nerves and blood vessels involved in sexual function and urination. That information can be crucial if a patient is considering surgery, radiation or watchful waiting.

More often, doctors are playing probabilities to determine whether early-stage cancers have spread beyond the prostate. Some use mathematical formulas based on a combination of PSA levels, a DRE and what's known as a Gleason score, a measure of a cancer's aggressiveness based on the pattern of abnormal cells seen on the biopsy.

And doctors often disagree about what that information signifies. In Mr. Edelman's case, one counseled watchful waiting since his Gleason score was a moderate six. Another doctor suspected Mr. Edelman's cancer had already spread, based on his PSA, and urged radiation and hormone therapy. At Memorial Sloan-Kettering Cancer Center in New York, Mr. Edelman had a second MRI that revealed that his cancer was still confined to the prostate, but was on both sides of the gland and had grown since the first MRI scan.

He opted for a radical prostatectomy last fall -- and he thinks he caught the cancer just in time. "I'm told I have more than a 95% chance of being around for a long time," he says. His last PSA was down to zero.

Doctors who use MRIs caution they aren't always definitive and can't see very small cancers, but even that can be useful. "If I don't see anything on an MRI, it helps reassure me you probably don't have a large, life-threatening cancer." says Peter Scardino, chief of urology at Memorial Sloan-Kettering.

"We are all like the blind men feeling the elephant," Dr. Scardino adds. "I don't rely just on the DRE, the PSA, the biopsy results or the MRI. But if we put all that information together, we can get a pretty good idea of what's going on."


Playing 'Battleship'

Rather than rely on imaging, a small but growing group of urologists prefer to bombard the prostate with more extensive biopsies. A "3D-mapping biopsy" takes 50 or more samples, five millimeters apart, throughout the gland. The needles are inserted through a grid that allows doctors to pinpoint the size, shape and location of any cancers. Practitioners liken it to playing the game Battleship with the prostate. Unlike a standard biopsy done through the rectum, a mapping biopsy is performed through the skin behind the scrotum with the patient under anesthesia.

The cost of a 3D-mapping biopsy is $5,000 to $6,000, due to the extensive pathology needed. They're far too costly and cumbersome for routine screening. But the technique can provide valuable information for making treatment decisions, and is increasingly covered by insurance and Medicare.

In the last three years, Dr. Barqawi at the University of Colorado has performed two hundred 3D-mapping biopsies on patients after they had had TRUS biopsies. Of them, 96 learned that their cancers were more extensive than the first biopsy showed. But 33 patients were reassured that their cancers were small and could just be watched.

Dr. Barqawi says 60 of the patients getting mapping biopsies learned that their tumors were so localized that they opted for new treatments known as targeted focal therapies. With these, doctors are able to destroy just the tumor with cryosurgery or specialized ultrasound and leave the rest of the prostate alone.

"Knowledge is power and that's especially true when managing patients diagnosed with early-stage disease to avoid un-needed surgeries," Dr. Barqawi says.


Molecular Markers

Scientists are also making headway in finding new molecular markers that may be able to signify not just the presence of cancer, but what its lethal potential is.

Researchers at the University of Michigan have identified a molecular waste product of tumors, called sarcosine, that is elevated in the urine of men with advanced prostate cancers. Researchers at Memorial Sloan-Kettering and elsewhere are studying circulating tumor cells -- bits of cancer cells that break off and enter the blood stream -- that may be able to indicate whether cancer has the potential to metastasize.

Some patients have more than one kind of prostate cancer, and scientists are developing PET scans and radioactive dyes that may one day be able to make different kinds of tumors light up like colored Christmas lights -- yellow for benign, red for really lethal.

"We've got potentially game-changing biomarkers that could get us out of the dilemma we are in with PSA," says oncologist Jonathan Simons, president of the Prostate Cancer Foundation, which funds some of that research. With the recent NEJM studies, he says, "We've been reminded again of how much work we need to do."



Saturday, 28 March 2009

Digital rectal prostate exam a ritual of doctor-patient bonding, for good and bad

The practice, and its awkwardness, will come less often into play as U.S. Preventive Services Task Force guidelines now advise against it for men age 75 and over.

By Anna B. Reisman

November 3, 2008

In August, the U.S. Preventive Services Task Force, a government-sponsored panel of medical experts, issued new recommendations regarding prostate cancer screening: Men ages 75 and over should no longer be screened for prostate cancer with the PSA blood test or digital rectal exam.

An unexpected benefit may be an improvement in the doctor-patient relationship. The rectal exam can be one of the odder moments between a patient and his doctor. Not long ago, for example, I saw a 75-year-old for his routine annual visit. Things were not going well for him.

His wife's dementia was worsening daily. She would leave the stove on, accuse him of stealing her things, holler at him day and night. And yet he could not imagine putting her in a nursing home.

His eyes, usually sparkling with delight, were dull. As I examined his heart and lungs, neck and belly, ankles and feet, he heaved a long sigh. I felt gloomy about his wretched situation.

I must have been preoccupied, because when it was time for the rectal exam, I bumbled my words. I asked him to lower his pants, but instead of saying "Lie on the table," I told him to lie on the floor. The patient and I burst out laughing.

Still chuckling, I stepped out of the room so he could get ready. To be sure, my bumble had brought levity to a traditionally awkward moment -- but why, I asked myself, did this encounter have to end with an examination of his anus?

I was drawn to primary-care medicine by the human connection that comes with the white coat and stethoscope, the prospect of people willing to share their everyday thoughts and deepest secrets, and their expectation that I would use this information to help them.

What I didn't fully grasp was that this intimacy also had a critical physical component -- one that came gloved and lubed.

I'd never imagined that performing rectal exams would become a daily reality. Most of my patients are men over 50, which means that I ask them if they'd like to be screened for prostate cancer.

Some inquire whether the PSA (prostate-specific antigen) blood test alone will suffice. I explain that it's most informative to have both the PSA and the digital exam: Some cancers hide in prostate nodules in men whose PSA readings are normal.

So for men under 75 and over 50 (earlier for higher-risk men) who wish to be screened, just as important as the PSA is the old-fashioned, low-tech way with a pair of rubber gloves, a foil packet of lubricating jelly and an index finger.

For years I didn't feel confident in my ability to do a good rectal exam. In medical school, we spent about two months learning the heart exam, maybe one month on the lungs. The rectal exam was granted a single session.

Not surprising: It's one thing for a parade of students to line up, stethoscopes ready, at the bedside of a chatty patient with a heart murmur; it's quite another to find a patient willing to roll over and endure a series of rectal exams by unskilled, anonymous fingers. The result: a culture of squeamishness.

During residency, I did a lot of rectal exams and tried to get a sense of the prostate's normal size and consistency. But often I wasn't sure of myself. Was a slight asymmetry a normal variant or something worrisome?

I probably sent too many patients to urologists earlier in my career because of my self-doubt, but that was better, I suppose, than missing something.

And although plenty of men will hop onto the exam table without hesitation, there's no shortage of reluctant and nay-saying patients, of awkward silences followed by excuses.

One patient I recall stole a glance at my hands, the muscles in his face relaxing ever-so-slightly when he looked at my fingers. "My old doctor," he said, "had thick fingers, like sausages."

Another said, "My other doctor did one a few months ago, I think." And another, "Next time, I promise." Many opt for the PSA without the rectal exam.

Back in my exam room, the patient lay on the exam table in a fetal position, pants down, buttocks exposed, testicles dangling.

I examined his rectal area for internal hemorrhoids, the subtle edge of an anal fissure, the flat cauliflower of an anal wart, and found none.

I touched the precise spot of the anal skin that elicits the mischievously named "anal wink reflex," a test of nerve function. I dabbed my finger with the jelly and eased it in against the muscular resistance until I touched the prostate.

To feel the whole prostate and distinguish between its two lobes, I bent my knees, turned my arm upside down and swiveled my finger to reach the other side of the gland. It was the size of an apricot, smooth and rubbery.

As usual, I grimaced: The rectum has muscles that clench and unclench at the slightest sensation, and it always feels odd to have my finger locked in that tight embrace. It doesn't get more intimate than this.

Then I closed my eyes and focused on all of the nerve endings packed closely in my fingertip. As my finger swept the prostate gland, I felt its normal consistency, its symmetry and, to my relief, not a single nodule.

It was almost a Zen moment: worlds of otherwise hidden information uncovered through careful probing -- earlier, via conversation; now, via a digit.

I wiped my finger on the stool-sample card and discarded my gloves. The old man looked over his shoulder from the table, the twinkle in his eyes returned. "Does this mean we're friends?"

There's nothing like an awkward joke to defuse an awkward moment. But thanks to the U.S. Preventive Services Task Force, there may now be fewer of both.