EMUC 2020: The Need for Confirmatory Biopsies in Patients on Active Surveillance Who Underwent Upfront MRI with Possible Targeted Biopsy

(UroToday.com) In a talk presented in the Oral Presentations session of the 12th European Multidisciplinary Congress on Urological Cancers (EMUC), Dr. Henk Luiting presented data regarding the somewhat controversial question of the role of a confirmatory biopsy in patients who are undergoing active surveillance diagnosed on the basis of MRI-informed biopsy.


Recent work utilizing the Sunnybrook cohort has shown that non-adherence to confirmatory biopsy is associated with worse cancer-related long-term outcomes, among men who are diagnosed with low-risk prostate cancer on the basis of systemic biopsy without MRI. However, Dr. Luiting pointed out that the European Association of Urology (EAU) guidelines currently recommend omitting confirmatory biopsies for men who have upfront MRI with systematic and targeted biopsies, based on a weak recommendation.

The authors identified patients in the PRIAS cohort who underwent upfront MRI prior to biopsy or had MRI within 6 months of inclusion and received targeted biopsy for identified lesions, defined as PIRADS 3 or greater. Additionally, on the surveillance protocol, all men subsequently underwent s second MRI with confirmatory biopsies within 2 years of inclusion.

The authors examined a total of 212 patients. Of these, 146 (69%) had a lesion PIRADS ≥3 on MRI. The median interval between the first and second MRI was 12 months (interquartile range 10 to 14 months). 66 patients had no targetable lesion on their second MRI and, of these, 2 reclassified to Gleason grade group 2 disease while none reclassified to Gleason grade group 3 or greater.

Reclassification to Gleason grade group 2 or greater and Gleason grade group 3 or greater occurred in 9 (22%) and 3 (7%), respectively, of patients with PIRADS 3 lesions,  in 19 (26%) and 8 (11%), respectively, of patients with PIRADS4 lesions, and in 10 (3%) and 5 (16%), respectively, of patients with PIRADS 5 lesions.

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The omission of systematic biopsies would have missed 6/32 (19%) of reclassification to Gleason grade group 2 or greater and 2/14 (14%) of reclassification to Gleason grade group 3 or greater. In contrast, the omission of targeted biopsies would have missed 9/32 (28%) of reclassification to Gleason grade group 2 or greater and 5/14 (36%) of reclassification to Gleason grade group 3 or greater.

Opting to omit biopsies in patients with a lower PIRADS score on their second MRI compared with their first would prevent 49/212 (23%) of biopsies at the cost of missing 7/40 (18%) of reclassification to Gleason grade group 2 or greater and 3/16 (18%) of reclassification to Gleason grade group 3 or greater.

Thus, the authors conclude that patients who have a negative second MRI may be spared confirmatory biopsies without significant risk of missing upgrading. However, all patients with a visible lesion on the second MRI, whether it is a lower score than the initial or not, should undergo confirmatory biopsy based on significant risks of reclassification.


Presented by: Henk B. Luiting, MD, Erasmus Medical Center, Rotterdam, Netherlands

Written by: Christopher J.D. Wallis, Urologic Oncology Fellow, Vanderbilt University Medical Center, Contact: @WallisCJD on Twitter at the 12th European Multidisciplinary Congress on Urological Cancers (EMUC) (#EMUC20 ), November 13th - 14th, 2020