MRI catches prostate cancers missed by standard biopsy

Multiparametric MRI has high diagnostic ability for anterior prostate cancer and was able to identify lesions missed by a standard transrectal 12-core prostate biopsy, according to a study published in the September issue of The Journal of Urology.

“Considering the current situation, in which overtreatment of early [prostate cancer] has become recognized as a serious problem worldwide, further developments in active surveillance and focal therapy are expected to overcome the drawbacks inherent to whole gland therapy,” wrote Yoshinobu Komai, MD, PhD, of Tokyo Medical and Dental University, and colleagues. “To select candidates for active surveillance and focal therapy, it is crucial to evaluate the entire prostate, including the anterior region.”

To assess the ability of multiparametric MRI to reveal anterior cancers missed by transrectal 12-core biopsy, the authors conducted a study involving the use of more comprehensive 3D 26-core prostate biopsies. These biopsies are a combination of transrectal 12-core and transperineal 14-core biopsies, allowing the researchers to identify cancers missed by the former technique but verified by the latter.

A total of 324 patients were included in the study, and all underwent multiparametric MRI and 3D 26-core prostate biopsy. Overall cancer rate based on the combined biopsy technique was 39 percent.

Of the patients with cancer, 28 percent had negative transrectal 12-core biopsies, according to Komai and colleagues. Twenty-six patients had an anterior lesion on imaging, but a negative 12-core biopsy. Overall, multiparametric MRI identified an anterior lesion in 20 percent of patients.

Less than 4 percent of patients without an anterior lesion on imaging had a cancer that also wasn’t identified by transrectal 12-core biopsy.

“Prebiopsy multiparametric magnetic resonance imaging has the potential to efficiently select men who could advantageously undergo anterior samplings, in addition to transrectal 12-core prostate biopsy,” summed the authors.