MRI-Targeted Prostate Biopsy Introduces Grade Inflation and Overtreatment

• Type of Material: Article
• Authors: Abderrahim Oussama Batouche, University of Helsinki; Eugen Czeizler, University of Helsinki; Timo-Pekka Lehto, University of Helsinki; Andrew Erickson, University of Helsinki; Tolou Shadbahr, University of Helsinki; Teemu Daniel Laajala, University of Helsinki; Joona Pohjonen, University of Helsinki; Andrew Julian Vickers, Memorial Sloan Kettering Cancer Center; Tuomas Mirtti, Emory University; Antti Sakari Rannikko, University of Helsinki
• Language: English
• Date: 2024-01-10
• Publisher: Cold Spring Harbor Laboratory
• Publication Version: Preprint (Prior to Peer Review)
• Copyright Statement: The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): https://www.medrxiv.org/content/10.1101/2024.01.10.24300922v1.article-info
• Title of Journal or Parent Work: medRxiv
• Volume: 2024
• Grant/Funding Information: This work was supported by grants from the Cancer Society Finland (Tuomas Mirtti and Antti Rannikko), Academy of Finland (Tuomas Mirtti), Sigrid Jusélius Foundation (Tuomas Mirtti), Jane and Aatos Erkko Foundation (Antti Rannikko) and state funding for university-level health research (Tuomas Mirtti and Antti Rannikko). This work was also supported in part by the National Institutes of Health/National Cancer Institute (NIH/NCI) with a Cancer Center Support Grant to Memorial Sloan Kettering Cancer Center [P30-CA008748], a SPORE grant in Prostate Cancer to Dr. H. Scher [P50-CA92629], a PCORI grant [ME-2018C2–13253], the Sidney Kimmel Center for Prostate and Urologic Cancers, and David H. Koch through the Prostate Cancer Foundation. The funding sources did not play any role in the study design, execution, data analyses, writing of the report, or submission of the article for publication.
• Keywords: Survival; Neoplasm Grading; Watchful Waiting; Magnetic Resonance Imaging; Recurrence
• Research Categories: Health Sciences, Radiology; Health Sciences, Oncology

Abstract

Purpose: The use of MRI-targeted biopsies has led to lower detection of Gleason Grade Group 1 (GG1) prostate cancer and increased detection of GG2 disease. Although this finding is generally attributed to improved sensitivity and specificity of MRI for aggressive cancers, it might also be explained by grade inflation. Our objective was to determine the likelihood of definitive treatment and risk of post-treatment recurrence for patients with GG2 cancer diagnosed using targeted biopsies relative to men with GG1 cancer diagnosed using systematic biopsies. Methods: We performed a retrospective study on a large tertiary centre registry (HUS Acamedic Datalake) to retrieve data on prostate cancer diagnosis, treatment, and cancer recurrence. We included patients with either GG1 with systematic biopsies (3317 men) or GG2 with targeted biopsies (554 men) from 1993 to 2019. We assessed the risk of curative treatment and recurrence after treatment. Kaplan-Meier survival curves were computed to assess treatment- and recurrence-free survival. Cox proportional hazards regression analysis was performed to assess the risk of posttreatment recurrence. Results: Patients with systematic biopsy detected GG1 cancer had a significantly longer median time-to-treatment (31 months) than those with targeted biopsy detected GG2 cancer (4 months, p<0.0001). The risk of recurrence after curative treatment was similar between groups with the upper bound of 95% CI, excluding an important difference (HR: 0.94, 95% CI [0.71–1.25], p=0.7). Conclusion: GG2 cancers detected by MRI-targeted biopsy are treated more aggressively than GG1 cancers detected by systematic biopsy, despite having similar oncologic risk. To prevent further overtreatment related to the MRI pathway, treatment guidelines from the pre-MRI era need to be updated to consider changes in the diagnostic pathway.