The diagnosis and treatment of prostate cancer is rife with controversy. Because it's such a slow-growing cancer and therapy carries significant risks, a case can be made to skip treatments altogether. But for men whose prostate cancers happen to be fast growing – or near the prostate wall – it's imperative to get an early, accurate diagnosis.

Akin to the function of mammography, the ProUroScan is a new medical imaging technology that creates a map or a digital record of the prostate to identify abnormalities detected by digital rectal exam (DRE).

"When we survey the prostate with our probe, we create a map, a 3-D picture of what a prostate would look like," Rick Carlson, CEO of ProUroCare Medical (Minneapolis), told Medical Device Daily. "Once we create the map for any patient with any condition of any type, it creates a baseline, which says we have a patient with a suspicious condition and now we know where it exists."

That map, created by this new method called prostate mechanical imaging (PMI), can be saved as a permanent electronic record and compared to other maps created in successive evaluations.

The American Cancer Society (Atlanta) estimates that there are more than two million men in the U.S. diagnosed with prostate cancer. One out of 35 men will die from this type of cancer, but it's difficult to identify those with aggressive disease. The two primary screening tests for prostate cancer, the DRE and the prostate specific antigen (PSA) blood test, are not 100% accurate. An abnormal result isn't a confirmation of cancer and a normal result doesn't mean cancer isn't present. Biopsies are another option, but unless the needle hits cancerous tissue, it can be missed.

Given these concerns and complications, ProUroCare has taken a different approach to the diagnostic process.

"Any soft tissue organ, by definition, does not generally have abnormal tissue formations unless there is something going on," Carlson said. "The map created by ProUroScan is akin to a weather map. We're measuring the displacement of tissue. The more tissue you displace the lighter the color. Any dark formations are an indication that elasticity is different. Over time, we'll be able to say that tissue is not only different, but in fact is most likely a cancer formation. As we see changes in the sizes in the elasticity being different it tells us if it's expanding or moving closer to the wall of the prostate. All are indications for physician that you may have a more progressive disease or a more benign disease."

Carlson explained that PMI is not ultrasound or thermal mapping, but a mechanical mapping done with the aid of a probe equipped with pressure sensor arrays.

"We would see this test being done repeatedly over time so that a physician would be able to compare changes that occur," he said.

To date, nine peer-reviewed articles have been published. The latest was in Urology last year. That study, led by ProUroScan co-inventor Armen Sarvazyan, PhD, founder and CSO of Artann Laboratories (Trenton, New Jersey), presented data from 168 patients.

In 84% of cases, PMI provided "data sufficient for quantitative assessment and image reconstruction of the prostate," the study authors wrote. "Four potential causes of the 16% failure became apparent: anatomical limitations such as position of the prostate relative to sphincter and/or bladder (5%), insufficient pressure applied (5%), excessive noise from sensors (4%), and inability of the examiner to locate the prostate upon insertion of the probe (2%)."

PMI successfully imaged 10 of 13 malignant nodules and was consistent with all eight reported biopsy-negative cases. For the same group, the DRE identified six of 13 cancer-positive cases and produced one false-positive result in the eight non-cancerous cases.

Overall, the study authors agreed that PMI "may significantly add to the technology diagnostic potential."

ProUroCare has since launched a new 40-patient study as required by the FDA for 510(k) approval that's expected to be completed in August.

If approved and launched, Carlson said the system, basically a small computer with a probe attached, would cost under $10,000 and would be used in a physician's office if either a DRE or PSA test were suspicious.

"Our goals is to make this a non-capital system purchase," he said, comparing it to the average $150,000 cost of an ultrasound machine. "We would see physicians having it in their offices and keeping their own images to compare over time.

Initially, the test (estimated to be $200) would have to be paid for by patients out of pocket but the company intends to pursue CPT coding.

Last year, ProUroCare entered into two agreements with Artann to complete development, conduct clinical trials and file for FDA clearance for ProUroScan (MDD, August 1, 2008).

If ProUroScan is approved for marketing, Carlson said the company will seek out a relationship with a larger medical device firm for marketing and distribution rather than building its own sales force.