Risks of Grade Reclassification Among Patients with Gleason Grade Group 1 Prostate Cancer and PI-RADS 5 Findings on Prostate MRI

• Published in: Urologic oncology 2024-12
• Main Authors: Sundaresan, Vinaik Mootha, Webb, Lindsey, Rabil, Maximilian, Golos, Aleksandra, Sutherland, Ryan, Bailey, Jonell, Rajwa, Pawel, Seibert, Tyler M., Loeb, Stacy, Cooperberg, Matthew R., Catalona, William J., Sprenkle, Preston C., Kim, Isaac Y., Leapman, Michael S.
• Format: Article
• Language: English
• Subjects: Active surveillance; genomic testing; Gleason upgrade; PI-RADS 5; prostate biopsy; Prostate cancer; prostate MRI
• ISSN: 1078-1439; 1873-2496; 1873-2496
• DOI: 10.1016/j.urolonc.2024.11.007

•Among individuals undergoing targeted biopsy of PI-RADS 5 lesions on prostate MRI, 15.2% were found to have Gleason Grade Group 1 prostate cancer•The majority of those managed with active surveillance (70.5%) experienced short term disease reclassification•Higher biopsy Decipher genomic classifier score was associated with biopsy Gleason reclassification among patients with PI-RADS 5 lesions and Gleason grade group 1 on initial biopsy•These findings support the role of confirmatory biopsy in patients with highly conspicuous prostate MRI findings and low-grade prostate cancer on initial biopsy As most Prostate Imaging Reporting and Data System (PI-RADS) 5 lesions on MRI harbor Gleason grade (GG) group ≥2 disease on biopsy, optimal management of patients with imaging-biopsy discordance remains unclear. To estimate grade misclassification, we evaluated the incidence of Gleason upgrading among patients with GG1 disease in the setting of a PI-RADS 5 lesion. We conducted a single-institution retrospective analysis to identify patients with GG1 prostate cancer on fusion biopsy with MRI demonstrating ≥1 PI-RADS 5 lesion. Primary study outcome was identification of ≥GG2 disease on subsequent active surveillance (AS) biopsy or radical prostatectomy (RP). We used multivariable models to examine factors associated with reclassification. We identified 110 patients with GG1 disease on initial biopsy and ≥1 PI-RADS 5 lesion. There were 104 patients (94.6%) initially managed with AS and six (5.5%) received treatment. Sixty-one patients (58.7%) on AS underwent additional biopsies. Of these, 43 (70.5%) patients had tumor upgrading, with 32 (74.4%) upgraded on first surveillance biopsy. Forty-four (40%) patients ultimately received treatment, including prostatectomy in 15 (13.6%) and radiation in 25 (22.7%). Two patients (1.8%) developed metastases. In multivariable models, genomic classifier score was associated with upgrading. Limitations include a lack of multi-institutional data and long-term outcomes data. Most patients diagnosed with GG1 prostate cancer on MRI-Ultrasound fusion biopsy in the setting of a PI-RADS 5 lesion were found to have ≥GG2 disease on subsequent tissue sampling, suggesting substantial initial misclassification and reinforcing the need for confirmatory testing.