MRI-guided Biopsy Research Articles

In-bore MRI targeted biopsy. Lights and shadows.

Multiparametric Magnetic Resonance Imaging (MpMRI) and MRI-guided biopsy (MRGB) are the diagnostic gold standard in the management of men with suspicious prostate cancer (PCa). There are not enough studies, yet, that compare TRUS-MRGB, COG-TB and IB-MRGB. Despite IB-MRGB could be more accurate in detecting PCa in smaller lesions and a less operator dependent technique, there are still some concerns regarding high resource costs and the chance of missing lesions not visible at MRI or detected by systematic biopsy.

Artificial Intelligence and Histopathological Diagnosis of Prostate Cancer

As of today, the diagnosis and management of prostate cancer involve the interpretation of data from multiple modalities and tools such as serum prostate-specific antigen levels, magnetic resonance imaging-guided biopsies, genomic biomarkers, and Gleason grading which are used to diagnose, risk stratify, and then monitor patients during respective follow-ups. Artificial intelligence (AI) can allow clinicians to recognize difficult relationships and manage enormous data sets, which is a task that is both extraordinarily difficult and time-consuming for humans. By using AI algorithms and reducing the level of subjectivity, it is possible to use fewer resources while improving the overall efficiency and accuracy in prostate cancer diagnosis and management. In this short review, we have made a case for the use of AI in the histopathological diagnosis of prostate cancer.

Long-term outcome of 9G MRI-guided vacuum-assisted breast biopsy: results of 293 single-center procedures and underestimation rate of high-risk lesions over 12 years

PurposeBreast magnetic resonance imaging (MRI) can detect some malignant lesions that are not visible on mammography (MX) or ultrasound (US). If a targeted, second-look fails, MRI-guided breast biopsy is the only available tool to obtain a tissue sample and pathological proof of these “MRI-only lesions”. The aim of this study is to report the performance and underestimation rate of 9G MRI-guided vacuum-assisted breast biopsy (VABB) over 12 years at a single center.Material and methodsAll 9G MRI-VABB procedures performed from January 2010 to December 2021 were retrospectively reviewed. Two MRI scanners (1.5 T and 3 T) were used with the same image resolution and contrast media. All suspicious lesions detected only by breast MRI underwent biopsy. Reference standard was histological diagnosis or at least 1-year negative follow-up. All malignant and atypical lesions underwent surgery, which was used as the reference standard.ResultsA total of 293 biopsies were retrospectively reviewed. Histopathological VABB results revealed 142/293 (48.4%) benign lesions, 77/293 (26.2%) high-risk lesions, and 74/293 (25.2%) malignant lesions. No significant complications were observed. Surgical pathology results allowed for the reclassification of n = 7/48 B3b lesions: n = 4 were ductal carcinoma in situ, while n = 3 presented invasive features at surgical histology (2 IDC; 1 ILC). B3b underestimation occurred overall in 14.6% of B3 cases. Breast follow-up was achieved for all benign VABB results, and only one false-negative case was observed.ConclusionOur results confirm that 1.5 T and 3 T MRI-guided VABB is an accurate and safe procedure for histopathologic final diagnosis of MRI-only lesions. Critical issues remain the potential high-risk underestimation rate of B3b VABB results and management of follow-up of benign lesions.

Machine learning prediction of Gleason grade group upgrade between in-bore biopsy and radical prostatectomy pathology

This study aimed to enhance the accuracy of Gleason grade group (GG) upgrade prediction in prostate cancer (PCa) patients who underwent MRI-guided in-bore biopsy (MRGB) and radical prostatectomy (RP) through a combined analysis of prebiopsy and MRGB clinical data. A retrospective analysis of 95 patients with prostate cancer diagnosed by MRGB was conducted where all patients had undergone RP. Among the patients, 64.2% had consistent GG results between in-bore biopsies and RP, whereas 28.4% had upgraded and 7.4% had downgraded results. GG1 biopsy results, lower biopsy core count, and fewer positive cores were correlated with upgrades in the entire patient group. In patients with GG>1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {GG}>1$$\\end{document}, larger tumor sizes and fewer biopsy cores were associated with upgrades. By integrating MRGB data with prebiopsy clinical data, machine learning (ML) models achieved 85.6% accuracy in predicting upgrades, surpassing the 64.2% baseline from MRGB alone. ML analysis also highlighted the value of the minimum apparent diffusion coefficient (ADCmin\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {ADC}_{\ ext{min}}$$\\end{document}) for GG>1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {GG}>1$$\\end{document} patients. Incorporation of MRGB results with tumor size, ADCmin\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\hbox {ADC}_{\ ext{min}}$$\\end{document} value, number of biopsy cores, positive core count, and Gleason grade can be useful to predict GG upgrade at final pathology and guide patient selection for active surveillance.

The ClearPoint Prism® Laser Ablation System: A New Platform for Laser Interstitial Thermal Therapy (LITT) in Neuro-Oncology

BACKGROUND AND OBJECTIVES: Laser interstitial thermal therapy (LITT) has advanced the surgical treatment of brain cancer. However, technical constraints in the first-generation laser ablation systems limit the full potential of this technology. The ClearPoint Prism® Laser Ablation System was developed to overcome many of these limitations, including a larger ablation window, a faster refresh rate for magnetic resonance thermometry, and integration with an MRI-compatible stereotactic system. This system was US Food and Drug Administration–cleared for neurosurgical use in 2022. METHODS: As an IDEAL Stage 1 study, we prospectively followed the first 3 patients who underwent LITT using the ClearPoint Prism® Laser Ablation System in the United States to establish feasibility and safety of this technology platform. RESULTS: Three patients underwent procedures involving MRI-guided needle biopsy followed by LITT. The radial error of stereotaxis relative to the intended target ranged from 0.8 to 1.6 mm (with a median of 1.0 mm). Definitive diagnosis was achieved in all cases. The average time required to establish the trajectories was 98.7 ± 16.6 minutes. The average time required to perform the biopsy and LITT was 110 ± 19.3 minutes. These times are not statistically different from our published results for comparable procedures using other available LITT systems. The average LITT time required to achieve ablation of >1 cm radius was 49 seconds (range: 29-133 seconds). There were no procedural complications. All patients were discharged home by postoperative day 3. The postoperative MRIs demonstrated expected ablation findings consistent with intraoperative thermometric assessment. With a median follow-up of 219 days (range: 185-259 days), there were no 30-day readmission, 90-day emergency visits, or wound complications. CONCLUSION: In this study, we introduced the design rationale for the ClearPoint Prism® Laser Ablation System, theoretical considerations for its technical merits relative to other existing systems, and to share our initial experience.

Magnetic resonance imaging-guided renal biopsy shows high safety and diagnostic yield: a tertiary cancer center experience.

To evaluate the technical success and outcomes of renal biopsies performed under magnetic resonance imaging (MRI) using a closed-bore, 1.5-Tesla MRI unit. We retrospectively reviewed our institutional biopsy database and included 150 consecutive MRI-guided biopsies for renal masses between November 2007 and March 2020. We recorded age, sex, BMI, tumor characteristics, RENAL nephrometry score, MRI scan sequence, biopsy technique, complications, diagnostic yield, pathologic outcome, and follow-up imaging. Univariate logistic regression was used to assess the association between different parameters and the development of complications. McNemar's test was used to assess the association between paired diagnostic yield measurements for fine-needle aspiration and core samples. A total of 150 biopsies for 150 lesions were performed in 150 patients. The median tumor size was 2.7 cm. The median BMI was 28.3. The lesions were solid, partially necrotic/cystic, and predominantly cystic in 137, eight, and five patients, respectively. Image guidance using fat saturation steady-state free precession sequence was recorded in 95% of the biopsy procedures. Samples were obtained using both fine-needle aspiration (FNA) and cores in 99 patients (66%), cores only in 40 (26%), and FNA only in three (2%). Tissue sampling was diagnostic in 144 (96%) lesions. No major complication developed following any of the biopsy procedures. The median follow-up imaging duration was 8 years and none of the patients developed biopsy-related long-term complication or tumor seeding. MRI-guided renal biopsy is safe and effective, with high diagnostic yield and no major complications. Image-guided renal biopsy is safe and effective, and should be included in the management algorithm of patients with renal masses. Core biopsy is recommended. • MRI-guided biopsy is a safe and effective technique for sampling of renal lesions. • MRI-guided biopsy has high diagnostic yield with no major complications. • Percutaneous image-guided biopsy plays a key role in the management of patients with renal masses.

Ex Vivo Fluorescence Confocal Microscopy of MRI-Guided Targeted Prostate Biopsies for Rapid Detection of Clinically Significant Carcinomas-A Feasibility Study.

MRI-guided prostate biopsies from visible tumor-specific lesions (TBx) can be used to diagnose clinically significant carcinomas (csPCa) requiring treatment more selectively than conventional systematic biopsies (SBx). Ex vivo fluorescence confocal microscopy (FCM) is a novel technique that can be used to examine TBx prior to conventional histologic workup. TBx from 150 patients were examined with FCM on the day of collection. Preliminary findings were reported within 2 h of collection. The results were statistically compared with the final histology. 27/40 (68%) of the csPCa were already recognized in the intraday FCM in accordance with the results of conventional histology. Even non-significant carcinomas (cisPCa) of the intermediate and high-risk groups (serum prostate-specific antigen (PSA) > 10 or 20 ng/mL) according to conventional risk stratifications were reliably detectable. In contrast, small foci of cisPCa were often not detected or were difficult to distinguish from reactive changes. The rapid reporting of preliminary FCM findings helps to reduce the psychological stress on patients, and can improve the clinical management of csPCa. Additional SBx can be avoided in individual cases, leading to lower rates of complications and scarring in the future surgical area. Additional staging examinations can be arranged without losing time. FCM represents a promising basis for future AI-based diagnostic algorithms.

Beyond the AJR: Can Prostate MRI and MRI-Guided Biopsy Be Cost-Effective in the United States in Patients With Elevated PSA?

Beyond the AJR: Can Prostate MRI and MRI-Guided Biopsy Be Cost-Effective in the United States in Patients With Elevated PSA?

Clinical benefits of MRI-guided freehand biopsy of small focal liver lesions in comparison to CT guidance

ObjectivesTo compare clinical success, procedure time, and complication rates between MRI-guided and CT-guided real-time biopsies of small focal liver lesions (FLL) < 20 mm.MethodsA comparison of a prospectively collected MRI-guided cohort (n = 30) to a retrospectively collected CT-guided cohort (n = 147) was performed, in which patients underwent real-time biopsies of small FLL < 20 mm in a freehand technique. In both groups, clinical and periprocedural data, including clinical success, procedure time, and complication rates (classified according to CIRSE guidelines), were analyzed. Wilcoxon rank sum test, Pearson’s chi-squared test, and Fisher’s exact test were used for statistical analysis. Additionally, propensity score matching (PSM) was performed using the following criteria for direct matching: age, gender, presence of liver cirrhosis, liver lobe, lesion diameter, and skin-to-target distance.ResultsThe median FLL diameter in the MRI-guided cohort was significantly smaller compared to CT guidance (p < 0.001; 11.0 mm vs. 16.3 mm), while the skin-to-target distance was significantly longer (p < 0.001; 90.0 mm vs. 74.0 mm). MRI-guided procedures revealed significantly higher clinical success compared to CT guidance (p = 0.021; 97% vs. 79%) as well as lower complication rates (p = 0.047; 0% vs. 13%). Total procedure time was significantly longer in the MRI-guided cohort (p < 0.001; 38 min vs. 28 min). After PSM (n = 24/n = 38), MRI-guided procedures still revealed significantly higher clinical success compared to CT guidance (p = 0.039; 96% vs. 74%).ConclusionDespite the longer procedure time, freehand biopsy of small FLL < 20 mm under MR guidance can be considered superior to CT guidance because of its high clinical success and low complication rates.Clinical relevance statementBiopsy of small liver lesions is challenging due to the size and conspicuity of the lesions on native images. MRI offers higher soft tissue contrast, which translates into a higher success of obtaining enough tissue material with MRI compared to CT-guided biopsies.Key Points• Image-guided biopsy of small focal liver lesions (FLL) is challenging due to inadequate visualization, leading to sampling errors and false-negative biopsies.• MRI-guided real-time biopsy of FLL < 20 mm revealed significantly higher clinical success (p = 0.021; 97% vs. 79%) and lower complication rates (p = 0.047; 0% vs. 13%) compared to CT guidance.• Although the procedure time is longer, MRI-guided biopsy can be considered superior for small FLL < 20 mm.Graphical

MRI-visualized T2 hyperintense breast lesions: identifying clinical and imaging factors linked to malignant biopsy outcomes.

To determine the malignancy rate for MRI-guided breast biopsies performed for T2 hyperintense breast lesions and to assess additional clinical and MRI characteristics that can predict benign and malignant outcomes. A retrospective chart review of consecutive MRI-guided breast biopsies performed in two tertiary hospitals was conducted over two years. Biopsies performed for T2 hyperintense lesions were selected, and further lesion imaging characteristics and patient risk factors were collected. Univariate and multivariate modeling regression were used to determine additional imaging and patient factors associated with malignant outcomes for biopsies of T2 hyperintense lesions. Out of 369 MRI-guided breast biopsies, 100 (27%) were performed for T2 hyperintense lesions. Two biopsy-proven benign lesions were excluded as the patient was lost on follow-up. With a study cohort of 98 lesions, the final pathology results were benign for 80 (80%) of these lesions, while 18 (18%) were malignant. Using multivariate logistic modeling, patient age > 50 (OR 5.99 (1.49, 24.08 95% CI), p < 0.05) and lesion size > 3cm (OR 5.54 (1.54-18.7), p < 0.01) were found to be important predictors of malignant outcomes for MRI biopsies performed for T2 hyperintense lesions. Our study observed a high malignancy rate, challenging the assumption that T2 hyperintensity can be considered a benign imaging characteristic for otherwise suspicious MRI-detected lesions. Decision-making regarding tissue sampling should be made based on a thorough evaluation of more reliable additional demographic and imaging factors, including patient age and lesion size.

Contrast-enhanced breast imaging: Current status and future challenges

BackgroundContrast-enhanced breast MRI and recently also contrast-enhanced mammography (CEM) are available for breast imaging. The aim of the current overview is to explore existing evidence and ongoing challenges of contrast-enhanced breast imaging. MethodsThis narrative provides an introduction to the contrast-enhanced breast imaging modalities breast MRI and CEM. Underlying principle, techniques and BI-RADS reporting of both techniques are described and compared, and the following indications and ongoing challenges are discussed: problem-solving, high-risk screening, supplemental screening in women with extremely dense breast tissue, breast implants, neoadjuvant systemic therapy (NST) response monitoring, MRI-guided and CEM- guided biopsy. ResultsTechnique and reporting for breast MRI are standardised, for the newer CEM standardisation is in progress. Similarly, compared to other modalities, breast MRI is well established as superior for problem-solving, screening women at high risk, screening women with extremely dense breast tissue or with implants; and for monitoring response to NST. Furthermore, MRI-guided biopsy is a reliable technique with low long-term false negative rates. For CEM, data is as yet either absent or limited, but existing results in these settings are promising. ConclusionContrast-enhanced breast imaging achieves highest diagnostic performance and should be considered essential. Of the two contrast-enhanced modalities, evidence of breast MRI superiority is ample, and preliminary results on CEM are promising, yet CEM warrants further study.

The role of PSA kinetics in men with a negative MRI-targeted prostate biopsy.

To evaluate rebiopsy rates and clinicopathologic outcomes in patients after a negative MRI-guided biopsy to better inform the management of these patients. Patients were included with a clinical suspicion of prostate cancer (PCa) referred for fusion biopsy for a PI-RADS v2.1 lesion ≥ 3 on multiparametric MRI and a negative MRI fusion biopsy. Biopsies included targeted and systematic cores. Patients with a prior cancer diagnosis were excluded. Both baseline and follow-up clinicopathological data, and long-term PSA values were examined in these patients. Statistical analyses included Wilcoxon rank-sum test and one-way tests. Of 685 total patients, 188 (27%) had a negative fusion biopsy. Of these 88 (47%), 74 (39%), and 26 (14%) had PI-RADS 3, 4, 5 lesions, respectively. Complete follow-up was available for 182/188 patients (97%), with a median of 24 months (interquartile range: 12-38). Post-biopsy PSA levels decreased the first and the second year (-0.24; and -0.84 ng/ml/yrs respectively). In follow-up, 44 patients had an MRI (24%) and 20 had a biopsy (10%). A positive PSA velocity was the only predictive variable for repeat MRI in univariate analysis. On repeat MRI, 9 (27%) patients had disappearance of the initial lesion, 21 (48%) had a lower PIRADS score and 14 (32%) higher. Only 12/182 (6.6%) were found to have PCa during follow-up, of those 7 (3.8%) were clinically significant. For patients with nonmalignant biopsy findings after an initial mpMRI showing a suspicious PI-RADS lesion, the majority of patients will have their PSAs return to baseline over time. To support this, repeat MRI frequently demonstrated a disappearance or downgrading of PIRADS lesions. These data support monitoring patients with this clinical scenario.

Lobular Neoplasia Diagnosed by MRI-Guided Breast Biopsy: Identifying Upgrade Rate to Malignancy and Outcomes of Clinical and Surgical Management.

The aim of this study was to determine surgical and clinical outcomes of lobular neoplasia (LN) diagnosed by magnetic resonance imaging (MRI) biopsy, including upgrade to malignancy, and to assess for characteristics associated with upgrade. A single-institution retrospective study, between 2013 and 2022, of patients with histopathological findings of LN via MRI-guided biopsy was performed using an institutional database and review of the electronic medical records. Decision for excision or surveillance was made by a multidisciplinary team per institutional practice. Patient demographics and imaging characteristics were summarized using descriptive analyses. Upgrade was defined as upgrade to cancer on surgical pathology for patients treated with excision or the development of cancer at the biopsy site during surveillance. The Wilcoxon rank-sum test and Fisher's exact test were used to compare features of the upgraded cohort with the remainder of the group. Ninety-four MRI biopsies diagnosing LN were included. Median age was 57 years (range 37-78years). Forty-six lesions underwent excision while 48 lesions were surveilled. The upgrade rate was 7.4% (7/94). Upgrades in the excised cohort consisted of pleomorphic lobular carcinoma in situ (LCIS; n=1), ductal carcinoma in situ (DCIS; n=3) and invasive lobular carcinoma (ILC; n=2), while one interval development of DCIS was observed at the site of biopsy in the surveillance cohort. No MRI or patient variables were associated with upgrade. In this contemporary cohort of MRI-detected LNs, the upgrade rate was low. Omission of surgery for MRI-detected LNs in carefully selected patients may be considered in a shared decision-making capacity between the patient and the treatment team. Larger cohorts are needed to determine factors predictive of upgrade risk.

Comparison of multiparametric and biparametric magnetic resonance imaging protocols for prostate cancer diagnosis by radiologists with different experience

BACKGROUND: Magnetic resonance imaging can detect clinically significant prostate cancer and diagnose extracapsular extension and cancer stage. A scanning protocol that includes only T2-weighted and diffusion-weighted images represents a viable alternative to multiparametric magnetic resonance imaging provided that the high diagnostic accuracy of the test is maintained. In recent studies, biparametric and multiparametric magnetic resonance imaging demonstrated slight differences in the diagnostic accuracy in detecting prostate cancer. AIM: To compare the diagnostic accuracy of biparametric and multiparametric magnetic resonance imaging for the detection of clinically significant prostate cancer using PI-RADS v2.1 with magnetic resonance imaging-guided multifocal biopsy as the gold standard. MATERIALS AND METHODS: This retrospective study initially processed the medical records of 126 patients. The inclusion criteria were as follows: presence of PI-RADS 2.1 multiparametric magnetic resonance imaging, clinical information on free and bound prostate-specific antigen blood levels, a multifocal prostate biopsy performed, and a time interval between magnetic resonance imaging and biopsy of no more than 14 days. Three investigators (radiologists with 2, 2–5, and 5 years of experience) independently evaluated biparametric magnetic resonance imaging of the prostate for the presence of pathological foci. After 2 weeks, the researchers evaluated the multiparametric magnetic resonance imaging dataset of the prostate. Each lesion detected, starting from PI-RADS category 3, was compared with the result of a multifocal fusion biopsy. The biopsy result was presented as a sum of Gleason scores, and a Gleason score of ≥7 was considered clinically relevant. According to magnetic resonance imaging data, findings meeting PI-RADS criteria 4 and 5 were considered tumor foci. RESULTS: The best values of sensitivity and specificity of foci detection on magnetic resonance imaging of the prostate gland were 62.5% and 74.6%, respectively. The highest diagnostic accuracy achieved was 70.1%. Magnetic resonance imaging had higher specificity rates for detecting prostatic foci when interpreted by radiologists with 2 years and 5 years of experience. CONCLUSION: Both biparametric and multiparametric magnetic resonance imaging of the prostate demonstrated suboptimal diagnostic accuracy. The sensitivity and specificity of the method tended to improve with increasing experience of the radiologist. Biparametric protocols of prostate scanning have a definite economic advantage over multiparametric protocols because of the absence of contrast agents and consumables and a significant decrease in magnetic resonance scanner loading time; however, their use can lead to a decrease in the diagnostic accuracy of the method.

CLINICAL VALUE OF MAGNETIC RESONANCE IMAGING-GUIDED CORE NEEDLE AND VACUUM-ASSISTED BREAST BIOPSIES

Breast cancer is the most common oncological disease in women. When changes in the breasts are not visible on an ultrasound or mammogram, they can be detected by a magnetic resonance imaging (MRI) scan. A biopsy of the breast tissue is performed to examine the changes and predict the most suitable further treatment method. Most often, a core needle biopsy is performed under ultrasound or mammography guidance, but if lesions are only visible on MRI images, the biopsy should be performed under MRI control. MRI-guided biopsy is a relatively new diagnostic method. The aim of our study was to assess the clinical value of MRI-guided core nee­dle and vacuum-assisted core needle breast biopsies. We conducted a systematic literature analysis. Articles were retrieved from PubMed and ClinicalKey electronic data­bases. Eligible articles were selected based on inclusion and exclusion criteria. 12 articles were included from 512 publications. We conclude that MRI -guided core needle and vacuum-assissted core needle biopsies are a safe and effective method of taking a breast tissue biopsy, allowing you to assess abnormalities that are not visible on mammography or ultrasound. MRI-guided biopsy is appropriate for all patients with suspicious lesions seen only on MRI, irrespective of breast cancer risk, as ma­lignant lesions are likely to be found in ~21% of patients. MRI-guided core needle biopsies have a low compli­cation rate. The diagnostic performance of MRI-guided core needle biopsy (sensitivity ~ 93%) is comparable to the diagnostic performance of other image-guided breast biopsy techniques.

Ultrasound-MRI Fusion Prostate Biopsy: Experience from a Cancer Center in the Midwest

Abstract Introduction/Objective Majority of literature with few exceptions suggests ultrasound-magnetic resonance imaging (MRI) fusion biopsy of prostate to be superior in diagnosing cancer compared to systematic transrectal ultrasonographic (TRUS) biopsy. However, it is highly dependent on the expertise of the person performing the biopsy and comes at a higher cost. The purpose of this study is a to evaluate the effectiveness of ultrasound-MRI fusion prostate biopsy at our institution. Methods/Case Report All prostate biopsies received at our institution from January to December 2022 were included. Data such as patient age, presence of region of interest (ROI) biopsy, presence of cancer in any core, presence of cancer in ROI core, total number of cores with cancer, highest Gleason score in ROI core, and highest Gleason score in other cores were collected. Results (if a Case Study enter NA) A total of 448 consecutive cases were identified. Of these 214 (47.8%) were transrectal ultrasonographic and 234 (52.2%) were ultrasound-MRI fusion biopsies. Mean age of patients with TRUS biopsy was 64.3±8.6 years and mean age of patients with MRI-guided biopsy was 65.4±6.9 years, a statistically comparable population (p-value 0.001). Among TRUS cases, 133 (62.1%) had tumor. Among ultrasound-MRI fusion cases, 169 (72.2%) had tumor. Among ultrasound-MRI fusion cases with tumor, 31 had cancer only in ROI core, 55 had cancer only in other cores and 83 had cancer in ROI core as well as at least one additional non-ROI core. Among 83 cases with tumor in ROI as well as non-ROI cores, 12 had higher Gleason score in ROI core, 18 had higher Gleason score in non-ROI core and in 53 cases the Gleason score in ROI core and highest Gleason score in any of the other positive cores were equal. Conclusion In our experience ultrasound-MRI fusion biopsy improves cancer detection; however, it does not improve the rate of detection of higher-grade cancer.

Cost-Effectiveness of Annual Prostate MRI and Potential MRI-Guided Biopsy After Prostate-Specific Antigen Test Results

Magnetic resonance imaging (MRI) and potential MRI-guided biopsy enable enhanced identification of clinically significant prostate cancer. Despite proven efficacy, MRI and potential MRI-guided biopsy remain costly, and there is limited evidence regarding the cost-effectiveness of this approach in general and for different prostate-specific antigen (PSA) strata. To examine the cost-effectiveness of integrating annual MRI and potential MRI-guided biopsy as part of clinical decision-making for men after being screened for prostate cancer compared with standard biopsy. Using a decision analytic Markov cohort model, an economic evaluation was conducted projecting outcomes over 10 years for a hypothetical cohort of 65-year-old men in the US with 4 different PSA strata (<2.5 ng/mL, 2.5-4.0 ng/mL, 4.1-10.0 ng/mL, >10 ng/mL) identified by screening through Monte Carlo microsimulation with 10 000 trials. Model inputs for probabilities, costs in 2020 US dollars, and quality-adjusted life-years (QALYs) were from the literature and expert consultation. The model was specifically designed to reflect the US health care system, adopting a federal payer perspective (ie, Medicare). Magnetic resonance imaging with potential MRI-guided biopsy and standard biopsy. Incremental cost-effectiveness ratios (ICERs) using a willingness-to-pay threshold of $100 000 per QALY was estimated. One-way and probabilistic sensitivity analyses were performed. For the 3 PSA strata of 2.5 ng/mL or greater, the MRI and potential MRI-guided biopsy strategy was cost-effective compared with standard biopsy (PSA 2.5-4.0 ng/mL: base-case ICER, $21 131/QALY; PSA 4.1-10.0 ng/mL: base-case ICER, $12 336/QALY; PSA >10.0 ng/mL: base-case ICER, $6000/QALY). Results varied depending on the diagnostic accuracy of MRI and potential MRI-guided biopsy. Results of probabilistic sensitivity analyses showed that the MRI and potential MRI-guided biopsy strategy was cost-effective at the willingness-to-pay threshold of $100 000 per QALY in a range between 76% and 81% of simulations for each of the 3 PSA strata of 2.5 ng/mL or more. This economic evaluation of a hypothetical cohort suggests that an annual MRI and potential MRI-guided biopsy was a cost-effective option from a US federal payer perspective compared with standard biopsy for newly eligible male Medicare beneficiaries with a serum PSA level of 2.5 ng/mL or more.

Quantification of Gleason Pattern 4 at MRI-Guided Biopsy to Predict Adverse Pathology at Radical Prostatectomy in Intermediate-Risk Prostate Cancer Patients.

Data on Gleason pattern 4 (GP4) amount in biopsy tissue is important for prostate cancer (PC) risk assessment. We aim to investigate which GP4 quantification method predicts adverse pathology (AP) at radical prostatectomy (RP) the best in men diagnosed with intermediate-risk (IR) PC at magnetic resonance imaging (MRI)-guided biopsy. We retrospectively included 123 patients diagnosed with IR PC (prostate-specific antigen <20 ng/mL, grade group (GG) 2 or 3, no iT3 on MRI) at MRI-guided biopsy, who underwent RP. Twelve GP4 amount-related parameters were developed, based on GP4 quantification method (absolute, relative to core, or cancer length) and site (overall, targeted, systematic biopsy, or worst specimen). Additionally, we calculated PV×GP4 (prostate volume × GP4 relative to core length in overall biopsy), aiming to represent the total GP4 volume in the prostate. The associations of GP4 with AP (GG ≥ 4, ≥pT3a, or pN1) were investigated. AP was reported in 39 (31.7%) of patients. GP4 relative to cancer length was not associated with AP. Of the 12 parameters, the highest ROC AUC value was seen for GP4 relative to core length in overall biopsy (0.65). an even higher AUC value was noted for PV × GP4 (0.67), with a negative predictive value of 82.8% at the optimal threshold. The lack of an association of GP4 relative to cancer length with AP, contrasted with the better performance of other parameters, indicates directions for future research on PC risk stratification to accurately identify patients who may not require immediate treatment. Incorporating formulas aimed at GP4 volume assessment may lead to obtaining models with the best discrimination ability.

INNV-29. THE CLEARPOINT PRISM® LASER ABLATION SYSTEM: A NEW PLATFORM FOR LASER INTERSTITIAL THERMAL THERAPY (LITT) IN NEURO-ONCOLOGY

Abstract BACKGROUND Laser interstitial thermal therapy (LITT) has advanced the surgical treatment of brain cancer. However, technical constraints in the first-generation laser ablation systems limit the full potential of this technology. ClearPoint Prism® Laser Ablation System was developed to overcome many of these limitations, including a larger ablation window, a faster refresh rate for magnetic resonance thermometry, and integration with an MRI-compatible stereotactic system. This system was FDA cleared for neurosurgical use in 2022. METHODS We prospectively followed the first three patients who underwent LITT using the ClearPoint Prism® Laser Ablation System in the U.S. to establish feasibility and safety of this technology platform. RESULTS Three patients underwent procedures involving MRI-guided needle biopsy followed by LITT. The radial error of stereotaxis relative to the intended target ranged 0.8-1.6 mm (with a median of 1.0 mm). Definitive diagnosis was achieved in all cases. The average time required to establish the trajectories was 98.7 + 16.6 minutes. The average time required to perform the biopsy and LITT was 110 + 19.3 minutes. These times are not statistically different from our published results for comparable procedures using other available LITT systems. The average LITT time required to achieve ablation of &amp;gt; 1cm radius was 49 seconds (range: 29-133 seconds). There were no procedural complications. All patients were discharged home by postoperative day three. The postoperative MRIs demonstrated expected ablation findings consistent with intraoperative thermometric assessment. With a median follow-up of 219 days (range: 185-259 days), there were no 30-day readmission, 90-day emergency visits, or wound complications. CONCLUSION In this study, we provide the clinical outcome of the first three patients in the U.S. who underwent LITT through the FDA cleared ClearPoint Prism® Laser Ablation System. The system has distinct advantages that warrant consideration in further investigations and clinical applications.

Significant Prostate Cancer in Patients with PI-RADS Category 3 Lesions: A Single-Center, Retrospective Cohort Study.

The Prostate Imaging-Reporting and Data System (PI-RADS) category 3 is the most ambiguous lesion with a variable clinically significant prostate cancer (CsPCa) detection rate. Prostate-specific antigen density (PSAD) has been investigated as an adjunctive factor to improve the diagnostic efficiency of PI-RADS categories. This study aimed to investigate the utility of PSAD as an adjunctive factor in predicting CsPCA risk in patients with PI-RADS 3 lesions. The patients with an initial PI-RADS 3 category lesion (n=142) scheduled for systematic and magnetic resonance imaging-guided prostate biopsy between 2018 and 2022 were retrospectively evaluated. Demographic and clinical variables, including PSAD, were collected. The rate of CsPCa was the primary outcome. The impact of PSAD on the CsPCa detection rate was the secondary outcome. The median age was 62 years. The rate of CsPCa was 8.5% (n=12). The patients with CsPCa have significantly lower prostate volüme and higher PSAD levels than those without CsPCa (p=0.016 and p=0.012). The cut-off values of PSAD in predicting CsPCa in all PI-RADS 3 patients and patients with CsPCa and clinically insignificant prostate cancer (n=26) were ≥0.181 ng/ml2. The sensitivity and specificity values for PSAD ≥0.181 ng/ml2 were of 75% (95% CI: 42.8%-94.5%) and 81.5% (95% CI: 73.4%-88.0%) in predicting CsPCa among PI-RADS 3 category. Conclusion: PSAD values higher than 0.181 ng/ml2 can be used as an adjunctive clinical parameter in predicting CsPCa in patients with PI-RADS 3 lesions and differentiating CsPCa from clinically insignificant prostate cancer cases.