Clinical Updates
Radiology
Newer imaging techniques superior in detecting and localizing prostate cancer
09/01/2008
Magnetic resonance (MR) imaging is playing an increasingly important role in the care of prostate cancer patients, including prostate cancer detection, disease staging and treatment planning. At UCLA, a team of radiologists, urologists, MRI scientists and technologists work together using advanced prostate imaging and surgical techniques, including robotically assisted prostatectomy, to enable more precise diagnosis and treatment. UCLA is also planning studies using MR imaging to guide highly accurate, non-invasive treatments for prostate cancer.
MR imaging
MR imaging includes up to four different diagnostic studies that allow physicians to evaluate a patient’s anatomy in exquisite detail, including detecting disease that may not be adequately assessed with other imaging methods, such as X-ray, ultrasound or computed tomography (CAT scans). MR imaging uses a powerful magnetic field, radio-frequency pulses and a computer to not only produce detailed pictures of internal body structures, but also to detect functional properties of cancers, including their chemical signatures. Research at UCLA and other institutions have shown that MR imaging is superior to other imaging modalities, such as transrectal ultrasound, in detecting and localizing prostate cancer.
Preoperative MR
imaging Surgeons at UCLA routinely use MR imaging prior to robotic surgery to provide a roadmap showing where the cancer is in relation to surrounding nerves and arteries that control sexual and urinary function. Recent studies at UCLA confirm that preoperative imaging can reduce surgical margins and offer better outcomes for urinary and sexual function. Ongoing studies at UCLA are also evaluating active surveillance with MR to help some men with low-risk cancers avoid radiation and surgery.
MRSI – magnetic resonance spectroscopic imaging
MRSI is a MR technique that detects chemical metabolites in the human prostate gland and distinguishes normal tissue from cancer cells based on the quantities of certain metabolites. It provides functional information on the metabolism and rate of cellular turnover for normal and cancerous tissue based on the levels of citrate, choline and other chemicals. With this information, radiation oncologists use simultaneous integrated boost (SIB) techniques to areas of increased tumor concentration to enhance tumor control. MR diffusion and MR perfusion imaging MR diffusion and MR perfusion imaging are now being routinely used to better detect and stage prostate cancer, helping surgeons plan minimally invasive surgeries and radiation oncologists target tumor more precisely. Diffusion imaging is a much faster technique than MRSI that, while not as finely detailed as conventional MR imaging, provides information on the degree of cellular crowding. In areas where cancer cells are multiplying rapidly, diffusion imaging can detect the greater crowding of cells. Diffusion imaging has been shown to have higher sensitivity for prostate cancer than conventional MR imaging. Perfusion imaging has nearly the same fine detail as conventional MR imaging, but provides a map of blood flow, which increases with the proliferation of cancer cells. Cancer cells cause proliferation of new blood vessels (neoangiogenesis), which alters blood flow. New MR techniques can detect this alteration in blood flow during infusion of MR contrast.
Comprehensive treatment
At UCLA, we will be investigating whether non-invasive techniques such as MRguided high-intesnsity focused US (MR HIFU) or minimally invasive techniques such as irreversible electroporation (IRE) can be used to carefully destroy prostate cancer cells while sparing urinary structures, nerves and blood vessels. We have a full range of therapeutic modalities, including surgical options such as open prostatectomy, laparoscopic and robotic prostatectomy and prostate cryotherapy. We also offer the complete array of radiation oncology treatments, including intensity modulated radiation therapy (IMRT), stereotactic body radiation therapy (SBRT), and brachytherapy. UCLA also has clinical trial options for patients with all stages and presentations of prostate cancer.