Addition of MRI-Targeted Biopsy Leads to more Reliable Diagnosis of Aggressive Prostate Cancer
Method May Allow More Patients to Safely Elect Active Surveillance Rather Than Immediate Treatment of Low-Risk Cancers
Using a combination of magnetic resonance imaging (MRI) to target and sample suspicious prostate tissue, along with a standard prostate biopsy, is significantly more likely to detect the most aggressive prostate cancers than standard biopsy alone. This finding, published today in the New England Journal of Medicine, could allow a higher percentage of prostate cancer patients to avoid unnecessary treatment for slow-growing prostate cancers that are not likely to spread.
The new study was conducted by National Cancer Institute (NCI) researchers including one who is now at the University of Maryland School of Medicine (UMSOM).
"This study demonstrated that using a combination of both types of biopsies leads to more detection of prostate cancers and is less likely to miss aggressive cancers that can spread and kill," says study co-author M. Minhaj Siddiqui, MD , FACS, an associate professor of surgery at UMSOM and a collaborating member of the NCI research team. "This is an important finding that will be practice-changing as we see more cancer centers adopting both types of biopsy methods. Those of us who have already adopted this cutting-edge technology can now give physicians and patients alike the confidence that their prostate cancer diagnosis is accurate and that hard-to- diagnose aggressive cancers are not being missed."
About one in nine men will be diagnosed with prostate cancer during his lifetime, according to the American Cancer Society. Most men diagnosed with prostate cancer do not die from it, and many have milder forms of the disease that do not require immediate treatment but can instead be carefully monitored, called active surveillance, to make sure the tumor is not growing or becoming more aggressive.
Traditional biopsies, that use ultrasound imaging to locate the gland and randomly remove 12 core tissue samples, have been known to miss aggressive cancers, however, so doctors have not felt comfortable relying on them for treatment guidance for fear of under-treating patients with deadly tumors. As a result, many men with milder forms of the disease have been over-treated with surgery or radiation which often leads to side effects such as impotence and incontinence.
In a targeted biopsy, MRIs of the suspected cancer are fused with real-time ultrasound images, creating a map of the prostate that enables doctors to pinpoint and test suspicious areas.
"With greater confidence in our ability to make an accurate diagnosis, we are better able to use more conservative approaches, such as active surveillance, to manage patients sparing them adverse side effects," says Dr. Siddiqui, who is also Director of Urologic Oncology and Robotic Surgery at the University of Maryland Marlene and Stewart Greenebaum Comprehensive Cancer Center (UMGCCC). The NCI-designated comprehensive cancer center offers MRI-targeted biopsy, with expanded treatment options, including focal therapy to surgically remove only the tumor, sparing the prostate.
For the study, Dr. Siddiqui and his colleagues evaluated 2,103 men who all had both traditional biopsies using ultrasound and targeted biopsies guided by MRIs to check for prostate cancer. They then examined the prostate glands of 404 of these patients who were diagnosed with prostate cancer and had their gland surgically removed; they found that aggressive cancers went undetected in 16.8 percent of the standard biopsies compared to 8.8 percent of MRI-targeted biopsies; when the two biopsy methods were combined, only 3.5 percent of aggressive cancers were missed.
"These findings suggest that combined biopsy provides improved diagnostic accuracy over either systemic or MRI-targeted biopsy alone and better predicts the result of final histopathological analysis," the researchers wrote in the study.
The NCI conducted the study with data collected from June 2007 to January 2019. In 2015, the same group of researchers published a study in JAMA that found that 30 percent more high-risk prostate cancers were diagnosed with MRI-targeted biopsy than with the traditional approach. In addition, 17 percent fewer low-risk cancers were diagnosed with the MRI-targeted biopsy, compared to the standard method. Dr. Siddiqui was the first author of the JAMA article. It led to large cancer institutions, such as UMGCCC, adopting both biopsy methods as the standard of care.
"This new study suggests that the prostate oncology community can feel confident in their cancer diagnoses and in adhering to the philosophy of helping low-risk patients avoid radical therapies," said UMSOM Dean E. Albert Reece, MD, PhD, MBA, University Executive Vice President for Medical Affairs and the John Z. and Akiko K. Bowers Distinguished Professor. "Quality of life is a crucial part of managing cancer, and patients should not have to experience unnecessary side effects from over-treatment."
About the University of Maryland School of Medicine
Now in its third century, the University of Maryland School of Medicine was chartered in 1807 as the first public medical school in the United States. It continues today as one of the fastest growing, top-tier biomedical research enterprises in the world -- with 45 academic departments, centers, institutes, and programs; and a faculty of more than 3,000 physicians, scientists, and allied health professionals, including members of the National Academy of Medicine and the National Academy of Sciences, and a distinguished two-time winner of the Albert E. Lasker Award in Medical Research. With an operating budget of more than $1.2 billion, the School of Medicine works closely in partnership with the University of Maryland Medical Center and Medical System to provide research-intensive, academic and clinically based care for nearly 2 million patients each year. The School of Medicine has more than $540 million in extramural funding, with most of its academic departments highly ranked among all medical schools in the nation in research funding. As one of the seven professional schools that make up the University of Maryland, Baltimore campus, the School of Medicine has a total population of nearly 9,000 faculty and staff, including 2,500 student trainees, residents, and fellows. The combined School of Medicine and Medical System ("University of Maryland Medicine") has an annual budget of nearly $6 billion and an economic impact more than $15 billion on the state and local community. The School of Medicine faculty, which ranks as the 8th highest among public medical schools in research productivity, is an innovator in translational medicine, with 600 active patents and 24 start-up companies. The School of Medicine works locally, nationally, and globally, with research and treatment facilities in 36 countries around the world. Visit medschool.umaryland.edu
About the University of Maryland Marlene and Stewart Greenebaum Comprehensive Cancer Center
The University of Maryland Marlene and Stewart Greenebaum Comprehensive Cancer Center is a National Cancer Institute-designated comprehensive cancer center in Baltimore. The center is a joint entity of the University of Maryland Medical Center and University of Maryland School of Medicine. It offers a multidisciplinary approach to treating all types of cancer and has an active cancer research program. It is ranked among the top 20 cancer programs in the nation by U.S. News & World Report. umgccc.org.
MRI-Targeted, Systematic, and Combined Biopsy for Prostate Cancer Diagnosis
M. Ahdoot, A.R. Wilbur, S.E. Reese, A.H. Lebastchi, S. Mehralivand, P.T. Gomella, J. Bloom, S. Gurram, M. Siddiqui, P. Pinsky, H. Parnes, W.M. Linehan, M. Merino, P.L. Choyke, J.H. Shih, B. Turkbey, B.J. Wood, and P.A. Pinto N Engl J Med 2020;382:917-28. DOI: 10.1056/NEJMoa1910038