ProUroCare Medical device monitors prostate cancer

  • Article by: THOMAS LEE
  • Star Tribune
  • November 29, 2009 - 4:19 PM

ProUroCare Medical Inc. is doubling down on prostate cancer detection.

The Eden Prairie-based start-up recently filed an application urging the Food and Drug Administration to approve a device that produces low-cost 3D images of the prostate gland. By measuring tissue elasticity, ProUroCare says its device can help doctors perform initial biopsies and then track how the cancer progresses over time.

"Prostate cancer is all about monitoring what happens," said CEO Richard Carlson. "If you make the assumption that you won't die from cancer unless it leaves the [gland], the most important element for treating the patient is to follow the disease over time."

But experts say the company needs large studies that track thousands of patients over years, if not decades, to prove its theory that such long-term "prostate maps" can produce better medical outcomes, a key component to winning reimbursement from Medicare and private payers.

Earlier this year, the New England Journal of Medicine published two separate ongoing studies that suggested digital rectal exams (DREs) and prostate-specific antigen (PSA) blood tests, two of the most common methods doctors use to screen for prostate cancer, did not significantly reduce mortality rates.

"It's not enough to just image the prostate," said Dr. Elizabeth Brown, medical director of Argenta Advisors in Woodbury, a consulting firm that specializes in reimbursement issues. "You have to show meaningful impact on the patient."

Investors, though, seem to like what they're hearing. Founded in 1998, ProUroCare, a lightly traded over-the-counter stock, has raised $5.4 million, including $1.6 million from a recent sale of stock warrants. Since June, ProUroCare shares have about quadrupled from 80 cents a share to Friday's close of $3.15.

Prostate cancer has long flummoxed doctors. The disease is progressive, meaning the patient can live with it for a long time if the cancer doesn't spread. That means detecting the cancer in its early stages, long a cornerstone belief of cancer treatment, may not help and may even lead to overdiagnosis and unnecessary treatment, doctors say.

To screen vulnerable patients, doctors normally conduct a DRE and/or PSA test. If they suspect something, they'll order a biopsy. But DREs and PSAs can be inaccurate. And a biopsy, in which doctors remove pieces of tissue from the gland, can't always locate the cancer or determine whether the disease warrants invasive surgery, radiation therapy or just "active surveillance."

"You don't have a good starting point," Carlson said. "If [DRE and PSA] are wrong the first time, they're equally inaccurate the second and third times. You are putting these patients in an enormous dilemma by saying that you have something but can't find it."

Normal vs. abnormal tissue

Using a relatively new technique called elasticity imaging, ProUroCare's device employs sensors and software that measure how the application of pressure to the prostate displaces surrounding tissue. Normal tissue is soft, flexible, and can stretch easily. Abnormal tissue, a sign of cancer, is harder and more rigid. Based on this data, the company says it can create detailed 3D maps that can assist doctors in performing biopsies.

"If we can eliminate the false positives from biopsies, there would be an enormous positive effect on treating prostate cancer" and lowering health care costs, Carlson said.

More importantly, the device can create a series of images for use in tracking how the cancer behaves over a period of time, "our ultimate goal," he said.

To gain reimbursement, the company initially plans to position its device as an "adjunctive" to DREs and PSAs, meaning a combination of the three can produce more accurate biopsies. But experts say ProUroCare may have a tough time proving that long-term monitoring makes a significant difference.

ProUroCare would need to conduct the type of expensive, long-term studies that few companies today seem willing or able to do, said Dr. David Schwartz, a radiation oncologist at Fairview Hospital in Minneapolis.

"You would need lots of people followed over a long time," Schwartz said. "You don't know if it works for at least 10 years. It can become irrelevant.

"I think there could be some value" in the ProUroCare technology, he continued. "But how does it fit? I don't know."

Uncertainty remains

After all, doctors can't even fully demonstrate that DRE and PSA screenings result in fewer deaths from prostate cancer.

One study published in the March edition of the New England Journal of Medicine tracked more than 76,000 men in 10 sites across the United States who received DREs and PSAs.

The study divided the men into two groups: One underwent annual screenings, while the control group received normal care.

After following the men for seven years, the study reported a death rate of 116 per 10,000 men in the screening group vs. 95 deaths per 10,000 in the control group.

In other words, there was little difference between the two groups.

A similar study in Europe, which focused on just PSA screenings, reported a 20 percent drop in deaths but "a high risk of overdiagnosis."

Concerned about rising health care costs, regulators and payers are pushing back against some tests, especially imaging.

In May, the Centers for Medicare and Medicaid Services declined coverage for virtual colonoscopies, 3D images created by CT scanners, for patients 65 years and older.

This past month, two scientific groups revised recommendations on breast and cervical cancer screenings, calling for delaying and reducing the frequency of such tests.

Amid this climate, devicemakers like ProUroCare face an uncertain future.

"Across the board, payers are requiring more information to support these technologies," Brown said.

Thomas Lee • 612-673-7744

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