Diagnosis of prostate cancer remains imperfect. Current methods of prostate biopsy are limited by over detection of slow-growing tumors and under detection of clinically relevant cancers.
Investigators at the University of California-Los Angeles Department of Urology have found that a new technique of targeted biopsy in a clinic setting, using local anesthesia, may improve diagnosis and aid in selecting which patients are suitable for active surveillance and which need focal therapy (noninvasive techniques for destroying small tumors within the prostate). Their results are published in The Journal of Urology.
"The technology exists to biopsy prostate tumors under magnetic resonance imaging (MRI) guidance and this has been shown to improve prostate cancer diagnosis," says first author Geoffrey Sonn, MD, Department of Urology, Institute of Urologic Oncology, University of California-Los Angeles. "But such procedures are time-consuming, costly, and impractical in most settings. Magnetic resonance ultrasound (MR-US) systems that fuse stored MR images with real-time ultrasound combine the resolution of MRI with the ease and practicality of ultrasound, offering a savings in time and cost, while potentially retaining the accuracy of MR-guided biopsy. However there are further limiting factors – the need for monitored anesthesia care, or a transperineal approach and general anesthesia."
Investigators report on the findings in a group of men who underwent MR-US fusion biopsy as outpatients at the UCLA Clark Urology Center. Of the 171 men in the study, 106 underwent biopsy for surveillance, while 65 had an increased prostate specific antigen (PSA) level but previously negative biopsies. All had a median PSA of 4.9 ng/ml and a median prostate size of 48 cc. Following a procedure lasting about 20 minutes, none of the patients required hospitalization.
The researchers found that a targeted biopsy was three times more likely to identify cancer than a systematic biopsy. The biopsies showed prostate cancer in 90 of the 171 men.
"The study yielded three key findings," reports Leonard S. Marks, MD, lead investigator, professor of urology and director of the UCLA Active Surveillance Program. "First, it demonstrated the ability to target and biopsy lesions in an office-based setting with the patient under local anesthesia. Second, adding targeted biopsies to systematic biopsies increased the rate of diagnosis of all cancers and, more importantly, Gleason 7 or greater cancer. In fact, 38% of men with Gleason 7 or greater cancer had disease which was detected only by targeted biopsies of lesions detected on MRI. Third, the level of suspicion on MRI correlates with cancer diagnosis overall and diagnosis of Gleason 7 or greater prostate cancers. The biopsies revealed prostate cancer in 16 of 17 men with a grade 5 lesion on MRI."
The study shows that targeted prostate biopsy may be useful in the three key situations of active surveillance, increased PSA but negative transrectal ultrasound (TRUS) biopsy, and selection for focal therapy. It may improve patient selection, making surveillance a more attractive option for patients while reducing progression to active treatment. It may also identify tumors missed on TRUS biopsy, sparing patients the discomfort of numerous negative biopsies and reducing the risk of delayed diagnosis of aggressive tumors.
"Finally, focal therapy has become an area of keen interest. This technique can spare patients the more invasive, morbid perineal template-mapping biopsy often required for focal therapy. Two recent studies using different MR-US fusion devices yielded similar results. "This substantiates the advantages of image-guided targeted biopsy using MR-US fusion" concludes Dr. Marks.
The investigators acknowledge that due to the low risk patient population studied, relatively few patients underwent radical prostate surgery. "It remains possible that some tumors may be missed by this technique," says Dr. Marks. Further work, including a detailed study correlating MRI, targeted biopsy results, and prostatectomy specimens is ongoing.
Commenting on the study, Dr. Bradford Hood and colleagues at the National Cancer Institute, NIH, write, "MR-US fusion guided biopsy unblinds the 'blind' biopsy and has great potential to supplement or replace 'blind' TRUS prostate biopsies. However, significant hurdles remain to broad adoption and the best approach is yet to be determined."
Linda Gruner | Source: EurekAlert!
Further information: www.elsevier.com
More articles from Health and Medicine:
Molecular sensor detects early signs of multiple sclerosis, Gladstone study finds
04.12.2013 | Gladstone Institutes
New compound for slowing the aging process can lead to novel treatments for brain diseases
04.12.2013 | The Hebrew University of Jerusalem
Quantum entanglement, a perplexing phenomenon of quantum mechanics that Albert Einstein once referred to as “spooky action at a distance,” could be even spookier than Einstein perceived.
Physicists at the University of Washington and Stony Brook University in New York believe the phenomenon might be intrinsically linked with wormholes, hypothetical features of space-time that in popular science fiction can provide a much-faster-than-light shortcut from one part of the universe to another.
But here’s the catch: One couldn’t actually ...
A star is formed when a large cloud of gas and dust condenses and eventually becomes so dense that it collapses into a ball of gas, where the pressure heats the matter, creating a glowing gas ball – a star is born.
New research from the Niels Bohr Institute, among others, shows that a young, newly formed star in the Milky Way had such an explosive growth, that it was initially about 100 times brighter than it is now. The results are published in the scientific journal, Astrophysical Journal Letters.
The young ...
EPFL scientists have shown how to achieve a dramatic increase in the capacity of optical fibers; Their simple, innovative solution reduces the amount of space required between the pulses of light that transport data
Optical fibers carry data in the form of pulses of light over distances of thousands of miles at amazing speeds. They are one of the glories of modern telecommunications technology.
However, their capacity is limited, because the pulses of light need to be lined up one after the other in ...
NASA's Hurricane and Severe Storms Sentinel airborne mission known as HS3 wrapped up for the 2013 Atlantic Ocean hurricane season at the end of September, and had several highlights. HS3 will return to NASA’s Wallops Flight Facility in Wallops Island, Va., for the 2014 Atlantic hurricane season.
During the 2013 mission, two unmanned Global Hawks flew from Wallops for the first time. The mission highlights included studying the Saharan Air Layer, following the genesis of a tropical storm, finding a unique hybrid core or center circulation in a redeveloped storm, obtaining measurements on the strongest side of ...
Nanosponges that soak up a dangerous pore-forming toxin produced by MRSA (methicillin-resistant Staphylococcus aureus) could serve as a safe and effective vaccine against this toxin.
This "nanosponge vaccine" enabled the immune systems of mice to block the adverse effects of the alpha-haemolysin toxin from MRSA—both within the bloodstream and on the skin. Nanoengineers from the University of California, San Diego described the safety and efficacy of this nanosponge vaccine in the December 1 issue of ...
04.12.2013 | Health and Medicine
04.12.2013 | Materials Sciences
04.12.2013 | Ecology, The Environment and Conservation
04.12.2013 | Event News
12.11.2013 | Event News
29.10.2013 | Event News