By Jana Soeldner Danger
City & Shore PRIME Magazine
One in seven men in the United States is diagnosed with prostate cancer annually, and 30,000 die of it. Now, a new test that combines MRIs of the gland and transrectal ultrasound (TRUS) images makes it possible for doctors to identify prostate tumors more accurately and effectively.
In the past, TRUS has been the main method for diagnosing prostate malignancies. But because ultrasound is low resolution and produces little soft tissue detail, it can be challenging to identify tumors with it, especially small ones, says Dr. David Taub, director of urologic oncology at Lynn Cancer Institute at Boca Raton Regional Hospital. Ultrasound also targets the peripheral areas of the gland and can miss cancers located in the front, midline and top portions, he says.
So with TRUS alone, knowing where to place needles during a biopsy was difficult, and doctors used a kind of scattershot method to conduct what many clinicians call a “blind” procedure. “We would shoot 12 large needles from the rectum into the prostate in a random pattern,” says Dr. Alex Lewis, a radiologist at LCIBRRH. “It’s the only area of the body that we would biopsy without targeting. It’s been very difficult because of where the gland is located.”
How It Works
Dr. Taub compares the new technique to using a GPS to locate a destination instead of a paper map. The procedure works like this: A patient with an elevated level of Prostate Specific Antigen (PSA) first undergoes an MRI scan of his prostate. “The MRI is much higher resolution than ultrasound,” Dr. Lewis says.
If doctors decide a biopsy is necessary, the image is uploaded to a robot, which links the MRI to images obtained in real time with an ultrasound probe. With these detailed, 3D views of the gland, the doctor uses the robot to send the biopsy needle directly to the suspicious area.
Among other benefits, the technique helps to avoid unnecessary biopsies. Nearly all the targeted prostate biopsies done at BRRH have been positive for cancer, while with the previous method, only about 10 percent were positive, Dr. Lewis says.
The technique provides an effective diagnostic option for patients with rising PSA values who have had previous negative biopsies, and it can reduce the number of biopsies for patients with small, slow-growing lesions that are being managed with “active surveillance,” or careful monitoring, rather than immediate treatment with surgery or radiation.
“It’s a huge improvement,” Dr. Taub says, “It allows us to avoid biopsies in some people and in others, to target a specific spot.”
Dr. Lewis likens the new procedure to breast cancer imaging. “It’s like a mammogram for men,” he says. “We now have a screening test for men that’s as good or better than mammography is for women.”