Magnetic resonance ultrasound fusion targeted biopsy is a better way to accurately diagnose prostate cancer, scientists from the University of California, Los Angeles, have found.
Prostate cancer is the sixth leading male cancer killer, and the most common cancer among American men. It develops very slowly over time and symptoms don’t usually show until it has reached an advanced stage. If diagnosed early, prostate cancer can usually be treated effectively. However, once it metastasizes – spreads beyond the prostate – it is much harder to cure.
Each year, there are about 240,000 people diagnosed with prostate cancer. Detecting the cancer can be very difficult, and biopsies often miss clinically relevant cancers. The finding, published in The Journal of Urology, will improve diagnosis and help decide whether active surveillance and focal therapy among patients is necessary.
According to Geoffrey Sonn, MD, Department of Urology, Institute of Urologic Oncology, University of California-Los Angeles:
“The technology exists to biopsy prostate tumors under magnetic resonance imaging (MRI) guidance and this has been shown to improve prostate cancer diagnosis. 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.”
There were 171 men who participated in the study at the UCLA Clark Urology Center, 106 underwent biopsy for surveillance and 65 had an increased prostate antigen (PSA) level but previously negative biopsies. The men had an average prostate size of 48 cc and PSA of 4.9 ng/ml.
The biopsies were carried out in under 20 minutes, under local anesthesia. Of the 171 men, 90 were diagnosed with prostate cancer.
Leonard S. Marks, MD, lead investigator, professor of urology and director of the UCLA Active Surveillance Program, said:
“The study yielded three key findings. 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 findings reveal that using magnetic resonance imaging (MRI) along with ultrasound fusion biopsy is a lot more successful at detecting prostate cancer compared to the conventional approach. It prevents delayed diagnosis and saves the patient from having to go through numerous transrectal ultrasound (TRUS) biopsies that could miss the cancer.
Dr. Marks added: “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”.
Dr. Bradford Hood and colleagues at the National Cancer Institute, NIH, said: “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.”
Further research is still necessary to confirm the benefits of using this new form of biopsy. A study correlating targeted biopsy results, MRI and prostatectomy specimens is underway.
There has been a lot of research that could make detecting the cancer a lot easier, with another study revealing a new technique that detects certain metabolites in urine samples that could indicate presence of the cancer.
Written by Joseph Nordqvist