Presentation Authors: Michael Ahdoot*, Amir H. Lebastchi, Johnathan Bloom, Patrick Gomella, Thomas Sanford, Sandeep Gurram, Graham R. Hale, Samuel Gold, Johnathan DiBianco, Sherif Mehralivand, Vladimir Valera Romero MD, Maria Merino, Bethesda, MD, M. Minhaj Siddiqui, College Park, MD, Peter L. Choyke, Brad Wood MD, Howard Parnes, Barris Turkbey, Peter A. Pinto, Bethesda, MD
Introduction: MRI-TRUS fusion prostate biopsy(FB), also referred to as â€œtargeted biopsyâ€, has been shown to improve detection of clinically significant prostate cancer and reduce the detection of indolent cancers. Given the improvements in MRI targeted biopsy many urologist and patients alike have questioned the need for extended systematic sextant biopsy(SB) when FB is possible. We sought to determine if SB is still necessary in the modern era of MRI targeted biopsy.
Methods: 1707 FBs and SBs were performed in 1699 men from 2007 to 2017 at the NCI Center for Cancer Research. Patient demographics, PSA levels, prostate volume, primary and secondary Gleason grades, Grade Group, number of MRI targeted lesions, number of cores obtained, and biopsy yield were recorded prospectively.
Results: The patient population consisted of men averaging 62.9-years-old (36-86) with a mean PSA 9.7ng/mL, and prostate volume of 59.5ml. Prostate cancer was detected in 846 patients by 12 core SB and in 840 patients by FB. When stratified by highest Gleason Pattern detected per patient, FB detected significantly less Gleason 6 disease than SB (14.2% vs 21.1%, p < 0.0001) and significantly more Gleason 7 (21.2% vs 18.5%, p=0.049) and Gleason 8-10 (13.6% vs 9.3%, p < 0.0001) diseases. In addition, Gleason 7 sub-stratification demonstrated substantially more Gleason 4+3 detection with FB vs SB (4.1% vs 2.5%, p=0.011). When stratified by Grade Group (Figure 1), FB detected 50% more Grade Group 3-5 cancers (n=300 vs 202, p < 0.0001) and 15.6% fewer Grade Group 1-2 cancers(p=0.00036). Of all Grade Group 3-5 cancers detected(n=285), 48.8% (n=139) were detected only on FB and 14.3%(n=41) were detected by SB alone(p < 0.0001). GG 3-5 cancers detected by SB alone represented only 2.4% of patients biopsied (Red box, Figure 1).
Conclusions: MRI targeted biopsy significantly increases the likelihood of detecting clinically significant cancer without a concomitant increase in detection of low grade disease. These finding strongly support the use of routine MRI targeted biopsy when possible. While systematic biopsy did lead to an increase in detection of indolent cancers, a sufficiently large proportion of aggressive cancers were detected on systematic biopsy only, suggested targeted biopsy alone does not perform well enough to forgo systematic biopsy at this time.
Source of Funding: This research was supported by the Intramural Research Program of the NIH, National Cancer Institute, Center for Cancer Research.