Pathologic outcomes of MRI invisible tumors in prostate cancer.

282 Background: Magnetic resonance imaging (MRI) invisible tumors are a diagnostic challenge in prostate cancer due to the lack of ability to reliably monitor these lesions radiographically or pathologically. The progression and natural history of these lesions are unknown and outcomes over time are unclear. Methods: Men with multiparametric MRI of the prostate and MRI/Transrectal ultrasound (TRUS) fusion guided biopsy were assessed for the presence of MRI invisible tumors (MIT). An MIT is defined as cancer detected only on extended sextant biopsy and not visible on MRI. All men first underwent an MRI/TRUS fusion biopsy with tracked extended sextant biopsy which originally detected the MIT. The original biopsy needle course sampling these MITs was tracked and set as a future target using the MRI/TRUS fusion platform. Men subsequently underwent a combined MRI/TRUS fusion biopsy, systematic extended sextant biopsy, and a Targeted Tracked biopsy of the MIT (TT-MIT) that was recorded and tracked from the original biopsy. We describe the outcomes of tracking these MITs and compare the ability to monitor them with TT-MIT biopsy as opposed to systematic extended sextant biopsy. Results: 105 MITs were identified, 84 (80%) of which were originally Gleason 6 tumors. The median time between biopsies was 16.6 months. The overall cancer detection rate with TT-MIT was 77.4% compared to 59.7% using systematic extended sextant biopsy. Using TT-MIT, these invisible tumors showed higher Gleason scores in 16 (15.2%) tumors. When TT-MIT was compared to the systematic extended sextant biopsy sampling the corresponding location, it showed increased Gleason scores in 30 (28.6%) MITs while 58 (55.2%) showed concordant pathology and 17 (16.2%) showed less aggressive pathology. Conclusions: The ability to follow MRI invisible tumors suggests that these tumors are more effectively tracked using TT-MIT biopsy technique. These MITs change over time and 15% of them will upgrade to higher Gleason scores. Tracking these tumors with TT-MIT biopsy increases cancer detection rate compared to standard sextant biopsy and more accurately samples these MITs, unveiling a more aggressive pathology.

Detection of clinically significant prostate cancer after negative fusion and systematic biopsy.

288 Background: MRI/Ultrasound fusion biopsy of the prostate has enhanced the detection of clinically significant prostate cancer (csPCa). Detection of csPCa is greatest when fusion and systematic biopsies are combined. However, the finding of a negative fusion and negative systematic biopsy in patients with suspicious lesion on imaging raises the question of either falsely positive imaging or a false negative biopsy. Methods: We retrospectively reviewed our database of patients undergoing MRI/transrectal US-guided fusion biopsy. All images were graded according to the Prostate Imaging Reporting and Data System version (PIRADS) 2.0. Patients underwent targeted biopsy followed by systematic 12-core double sextant biopsy within the same session. csPCa was defined as Grade Group (GG) ≥2 PCa. Patients with no prostate cancer (PCa) found on biopsies were followed. MRI studies with PIRADS v2 score ≤ 2 were considered to have no MRI evidence of PCa. Results: A total of 400 patients had at least one PIRADS ≥3 lesion and underwent fusion/systematic biopsy. Of these, 113 (28.3%) patients had no evidence of PCa on either fusion or systematic biopsy. Median follow-up was 32.5 months. 44 (39%) patients underwent repeat MRI and of these, 24 (54%) had no evidence of PCa on repeat MRI. PIRADS lesion disappearance was associated with lower PSA Density (PSAd) (0.12 vs 0.20; P = 0.0319) and decreased progression to repeat biopsy (8.33% vs 95%; P < 0.0001). Patients who had a repeat biopsy had a greater PSAd ( 0.21 vs 0.12; P = 0.0054). Of 113 patients with negative initial biopsy, 23 (20.4 %) underwent repeat biopsy: 16 (14.2 %) had PCa and 11 (9.7%) had csPCa. Thus, 48% of patients who underwent repeat biopsy had csPCa. Among patients with a PCa on repeat biopsy, cancer was sampled by MRI targeted cores in 80% of patients. Conclusions: Despite a negative initial fusion/systematic biopsy, at least 10% of patients were subsequently diagnosed with clinically significant PCa. The combination of elevated PSAd and the persistence of a suspicious lesion on repeat MRI appears selective for previously missed PCa. However, after negative fusion biopsy, repeat MRI yields a high rate of PIRADS lesion disappearance in patients with low PSAd.

Prostate Biopsy Processing

Objectives Current protocols for processing multiple prostate biopsy cores per case are uneconomical and cumbersome. Tissue fragmentation and loss compromise cancer diagnosis. We sought to study an alternate method to improve processing and diagnosis of prostate cancer. Methods Two sets of sextant biopsy specimens from near-identical locations were obtained ex vivo from 48 prostate specimens. One set was processed in the standard fashion while the other was processed using the BxChip, a proprietary biomimetic matrix that accommodates six cores on a single chip. Parameters including grossing, embedding, sectioning and reading time, length of tissue, and degree of fragmentation were compared. Results A significant reduction (more than threefold) in preanalytical and analytical time was observed using the multiplex method. Nonlinear fragmentation was absent, in contrast to standard processing. Conclusions The BxChip reduced tissue fragmentation and increased efficiency of prostate biopsy diagnosis. It also resulted in overall cost savings and significantly increased tissue length.

MRI targeted biopsy dramatically increases detection of clinically significant prostate cancer while reducing the risk of indolent cancer detection.

108 Background: MRI fusion prostate biopsy has been shown to improve detection of clinically significant prostate cancer, however the degree of this benefit is poorly characterized in large clinical trials. Methods: 1750 MRI targeted plus sextant biopsies were performed in 1742 male patients from 2007 to 2017. Patient demographics, PSA, prostate volume, primary and secondary Gleason scores, Johns Hopkins Grade Groups, number of MRI targeted lesions, number of cores obtained, and biopsy yield were recorded. Results: The patient population consisted of men averaging 62.9-year-old (36-86) with a mean PSA 9.6ng/mL, and prostate volume of 59.2 ml. A total of 804 cancers were detected on sextant biopsy and 839 were detected on MRI targeted biopsy. Relative to targeted biopsy, sextant biopsy detected only significantly more Gleason 6 disease (14% vs 21.5%, p < 0.0001) than targeted biopsy. Targeted biopsy detected more Gleason 7 (21% vs 16.6%, p = 0.0009) and Gleason 8-10 (13.4% vs 9.4%). Additionally, Gleason 7 sub-stratification demonstrated substantially more Gleason 4+3 detection in targeted group vs sextant biopsy (4% vs 0.5%, p < 0.0001). When stratified by Grade Group targeted biopsy detected 76% more Grade Group 3-5 cancers (p < 0.0001) and 17.7% less Gleason Group 1-2 cancers (p < 0.0001). Only 1.7% of Grade Group 3-5 cancers were detected on sextant biopsy alone, where as 15.7% of Grade Group 3-5 cancers were detected on targeted biopsy alone. Conclusions: MRI targeted biopsy significantly increases the likelihood of detecting clinically significant cancer and decreases the risk of indolent cancer detection. These finding strongly support the use of MRI targeted biopsy when possible.

The Initial Experience of Trans-Rectal Ultrasound and Biopsy in Diagnosis of Carcinoma Prostate In Gezira Hospital For Renal Disease And Surgery (GHRDS)

<p><strong>Background</strong>: Prostate cancer prevalent cancer in males above sixty-five worldwide, this lead to the introduction of screening of the PSA and using of the transrectal ultrasound scanning, and sextant biopsy of the prostate.</p><p><strong>Objectives</strong>: To compare the accuracy of the Transrectal Ultrasound guided biopsy (TRUS/BX) in the diagnosis of prostate cancer in Gezira Hospital for Renal Diseases and Surgery (GHRDS), with specific considerations to the digital rectal examination (DRE) findings and prostate specific antigen (PSA) level. .</p><p><strong>Materials and Methods</strong>: This is a prospective, descriptive small-scale hospital based study. A total of 297 patients with clinically symptomatic enlarged prostate underwent transrectal ultrasound guided true cut needle biopsy of the prostate were studied in (GHRDS) in the period from June2006 to June2009. </p><p><strong>Results</strong>: The majority 188 (63.3%) of patients were between 50-70 years of age. Abnormal digital rectal examination (DRE) like obliteration of the median sulcus, and fixed mucosa revealed higher incidence of carcinoma prostate (CaP) with a significant value (p= 0.0000). PSA level showed significant relation (p= 0.0001) with the diagnosis of carcinoma prostate. Transrectal U/S findings well correlated to the histopathological results, where abnormal findings (like hypo-echoic lesions or calcifications and cysts) showed higher incidence of malignancy in 46 patients constitute 52.8% of the abnormal U/S findings.</p><p><strong>Conclusions and recommendations</strong>: PSA level is highly sensitive but less specific in detection of prostate cancer. Normal DRE doesn’t exclude prostate cancer, fixed mucosa and obliterated median sulcus has the highest predictors of cancer prostate in DRE. Presence of calcifications and cyst on trans-rectal ultrasound has the highest liability for cancer prostate in compare to the other ultrasonic findings. </p><p><strong>Key words: </strong>Prostate cancer, DRE, PSA level, TRUS/ BX (Transrectal ultra sound biopsy), sextant biopsy.</p>