By Jerry Berger | Beth Israel Deaconess Medical Center Staff
Beth Israel Deaconess Medical Center (BIDMC) is combining the latest in magnetic resonance imaging (MRI) technology with state-of-the-art computer software to more accurately diagnose and treat prostate cancers.
The capabilities are derived from the combination of the latest developments in MRI hardware and software. On the hardware side, the implementation of a General Electric high field strength MRI unit operating at 3T (T for Tesla, or a unit of measuring magnetic strength) and the development, by Medrad, Inc., of a specialized coil to detect the MRI signal enable imaging of the prostate gland at higher spatial resolution than previously possible.
This capacity has been combined with a software analysis tool developed by Israel’s Weizmann Institute that yields color-coded images that display benign images in green – and cancerous lesions in red.
To date, a prostate cancer diagnosis has been made by taking data from biopsies, digital exams and blood tests and combining them into a table that predicts the probability that a patient has cancer. While MRI has been somewhat useful in trying to pinpoint the location and extent of tumors within the prostate, the technology was not sophisticated enough to reliably map small, early stage lesions.
«These new tools will enable us to improve the accuracy of diagnosis and devise a treatment plan specific to the patient,» says Dr. Neil Rofsky, director of BIDMC’s MRI services. «It helps to reduce guess work and provide very specific targets for surgery or radiation therapy. It allows us for the first time to provide an objective means to non-invasively follow patients when immediate treatment is not required.»
Previously, the best way to determine the nature of a tumor was through rapid sampling of images during the administration of contrast material, a ‘dye’ injected into a patient’s vein. One drawback, however, is that small tumors could elude detection if they fell into the «slice» made by the MRI. The new 3T MRI enables «slices» 2 millimeters in size rather than the 5-7 millimeters common from older versions. The 3TP software uses an analysis that allows for longer time sampling, thus enabling the pursuit of high spatial resolution.
After the images are taken, radiologists turn to the 3TP software developed by Hadassa Degani, PhD, at the Weizmann Institute. Her formula measures tissue characteristics at three distinct time points and assigns a color to each pixel of the image, so that malignancies appear in red.
Armed with this information, urological surgeons or radiation oncologists are able to create a personalized treatment plan that would use either surgery to remove the cancer with the least amount of damage to surrounding tissue or nerves or brachytherapy – the implantation of radioactive «seeds» – to better focus radiation dose.
«This new improvement in MRI technology opens new avenues for optimizing individualized prostate cancer care to maximize quality of life» says Dr. Martin Sanda, associate professor of urology at Harvard Medical School and director of BIDMC’s Prostate Care Center, which takes a multidisciplinary approach to care, ranging from the evaluation of elevated PSA and performing prostate biopsies, to providing surgical, radiation, systemic or expectant (watchful waiting) treatment, based on patients’ individual needs and personal lifestyle priorities.
Above content provided by Beth Israel Deaconess Medical Center. For advice about your medical care, consult your doctor.
Posted September 2009
