By Raman Unnikrishnan, MD
Detecting prostate cancer can be notoriously difficult, as can deciding whether to treat or simply monitor confirmed or suspected malignancies.
Thankfully, a new diagnostic technology called fusion-guided biopsy is improving our ability to find the more aggressive cancers that do require early intervention. Unlike older screening tools, the UroNav Fusion Biopsy System offers detailed, real-time maps of the soft tissues of the prostate by combining MRI and ultrasound images.
Our hope is to reduce unnecessary surgeries, repeated biopsies and other therapies that can cause troubling side effects like erectile dysfunction, urinary incontinence and anxiety for patients who may have a slow-growing, non-lethal tumor – or no cancer at all.
Before the 1980s, prostate cancer screening involved digital rectal exam alone, and the disease often went undetected until presenting in advanced stages. Since then, the prostate specific antigen blood test, or PSA, has caught significantly more cases, including many low-risk malignancies that may not need treatment.
These tools have other significant diagnostic limits. Rectal exams only allow for access to part of the gland and may miss anterior tumors. As for the PSA, other medical conditions such as inflammation and benign prostatic hyperplasia can cause elevated levels of the same protein that increase with cancer.
Ultrasound-guided biopsies require multiple needles to sample mapped out areas of the prostate in hopes that if a tumor is present, one of the needles will pierce it. MRI images are much more distinct, allowing radiologists to mark suspicious areas for further examination with an ultrasound probe. The “fusion” software overlays US and MRI images during the procedure, providing a live, three-dimensional view and critical guidance to direct biopsy needles to precise points.
Fusion-guided biopsy can still miss tumors, but they tend to be the clinically insignificant ones – which is good news. The technology has 85 to 95 percent sensitivity for intermediate- and high-risk cancers that are more likely to metastasize and become life-threatening.
We currently are targeting fusion biopsy to two groups of men: patients with worrisome PSA levels who’ve previously had a negative biopsy who might otherwise have to go undergo another standard biopsy; and patients who are on active surveillance for prostate cancer for what we believe, but would like to confirm, are only low-risk tumors.
This spreading technology is already a great leap forward in the quest to reduce hundreds of thousands of unnecessary interventions each year – and to catch the dangerous cancers that do matter to survival.
Dr. Unnikrishnan is based at Urology of Virginia’s Portsmouth and Virginia Beach locations and is a member of the American Urological Association. He completed a residency in urology at the Cleveland Clinic and specializes in robotic-assisted and minimally invasive surgery, stone disease and benign and malignant conditions of the bladder, prostate and kidney. www.urologyofva.net
