The safety of determining candidacy for AS in this group, however, hinges on accurately detecting aggressive histologic variants, specifically cribriform and intraductal carcinoma (IDC). These patterns are associated with higher rates of distant metastasis, biochemical recurrence, and higher cancer-specific mortality. The presence of cribriform and/or IDC ultimately renders these patients poor candidates for AS.
In this retrospective study, we identified over 600 patients with GG 2-3 PCa who underwent MRI-assisted biopsy followed by radical prostatectomy. We sought to determine how often MRI-assisted biopsy correctly identified cribriform and/or IDC patterns– findings that would likely shift patients away from AS and toward definitive treatment.
We found that the sensitivity for detecting cribriform or IDC was modest – 21.8% and 26.8%, cribriform and IDC, respectively. Even among patients with high PIRADS lesions (scores 4–5), sensitivity remained low, at just over 32%. We were very interested in what factors could predict a false negative result. Notably, patients with GG 3 cancer or PSA levels over 10 ng/mL with biopsies showing no cribriform or IDC were more likely to have cribriform or IDC histology at the time of surgery, suggesting these clinical factors may help flag patients at risk for under-detection.
The results of this study have important implications for choosing appropriate candidates for AS. If AS is being considered for a patient with intermediate-grade disease, particularly in patients with GG 3 disease or a PSA greater than 10, clinicians should be aware of the high false-negative rates of these aggressive patterns. These findings should also encourage improvements in diagnostic strategies—including advanced imaging, targeted biopsy techniques, or the development of molecular and genomic biomarkers.
Written by: Raeven S. Grant, BS,1 and Adam B. Weiner, MD1-3
- Department of Urology, David Geffen School of Medicine, University of California-Los Angeles, Los Angeles, California, USA.
- Department of Urology, Cedars-Sinai Medical Center, Los Angeles, California, USA.
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA.