Additional Biopsies Research Articles

Additional Intestinal Mucosal Biopsy Sampling for Research Is Safe During Pediatric Endoscopic Procedures

Advancing the understanding of inflammatory bowel disease (IBD) pathogenesis has been facilitated by mechanistic studies that require human intestinal tissue. Enrolling pediatric subjects into these studies improves our knowledge of IBD in this underserved population. Given the additional research protections granted to children, institutional review boards (IRBs) must weigh the benefit of obtaining research biopsies against perceived risks. Although obtaining clinical biopsies from children is generally considered safe, there are only limited data on the safety of obtaining research biopsies in children.1-6.

Laparoscopic sleeve gastrectomy reverses non-alcoholic fatty liver disease modulating oxidative stress and inflammation

Background & aimsHepatic alterations, such as in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are frequently associated with obesity. To investigate the molecular mechanisms of these alterations and to identify molecules that could be used as potential therapeutic targets, we investigated the modulation of hepatic indices of oxidative stress and inflammation in obese patients undergoing laparoscopic sleeve gastrectomy (LSG). MethodsPatients (n = 436) attending our obesity clinic underwent LSG for weight loss. We obtained a diagnostic intraoperative liver biopsy, and a sub-cohort (n = 120) agreed to a 1-year follow-up that included donation of blood samples and additional liver biopsies. Selected key molecules in blood and liver tissue were used to investigate the hepatic alterations in obesity, and their response to LSG. ResultsOne year post-surgery, the prevalence of diabetes, dyslipidemia and hypertension decreased significantly. LSG improved liver histology features in all patients. Improvement was greater in severe cases of NAFLD including those with steatohepatitis, bridging fibrosis or cirrhosis. Significant pre-surgery differences in plasma, and liver markers of oxidative stress and inflammation (including chemokine C-C motif ligand 2, paraoxonase-1, galectin-3, and sonic hedgehog) were observed between patients with, and those without, NASH; post-surgery indicated consistent improvements in these parameters. ConclusionOur study shows that the histology and liver function of patients with morbid obesity are significantly improved after LSG via mechanisms that involve the reduction of oxidative stress and inflammatory processes. These data encourage the use of LSG as a therapeutic option to improve, or resolve, NAFLD.

Abstract 407: Gene expression and mutation profiles of single lung circulating tumor cells

Abstract In the era of personalized medicine, many targeted therapies have been developed against cancer-specific antigens, which have greatly improved patient outcome. The efficacy of targeted therapies was first shown in patients with non-small cell lung cancer (NSCLC) containing activating epidermal growth factor receptor (EGFR) mutations who responded to tyrosine kinase inhibitors (TKIs). To determine if a patient qualifies for targeted therapy, the patient must undergo a tumor biopsy. Usually done at the time of diagnosis, this single time-point examination dictates the treatment plan. Despite strong initial response to TKI therapy, nearly all patients develop resistance, most commonly by acquiring a secondary EGFR mutation. At the time of halted response, an additional biopsy may be necessary to screen for the presence of these secondary, resistance-causing mutations. Circulating tumor cells (CTCs) are cancer cells present in the blood that provide an alternative to an invasive tumor biopsy. Shed from the primary tumor, CTCs circulate throughout the vasculature, and extravasate leading to metastasis. CTCs have been shown to carry tumor-matched characteristics in both genotype and phenotype. Easily accessed through a blood draw, they can be used to serially track patients throughout treatment to detect the early emergence of new tumor clones. One of the biggest hurdles with CTCs being clinical prognostic markers is their low abundance in the blood. We have previously developed a high-throughput, label-free microfluidic technology, the Labyrinth, to isolate CTCs from the blood of breast, lung, and pancreatic cancer patients. This technology allows for quick and efficient isolation of CTCs from the millions of surrounding blood cells. After isolation, the CTCs are used for enumeration or single cell analysis. The single cell gene expression analysis performs a highly multiplexed RT-qPCR of a pre-designed 96 gene panel. Here we report a complementary single cell analysis approach to detect the presence of EGFR point mutations, L858R and T790M, implicated in TKI response using digital PCR (dPCR). dPCR is a highly sensitive approach which enables detection and quantification a single-cell level. dPCR relies on small sample loading and partitions the sample into individual PCR reaction droplets. This single molecule resolution provides the ability to distinguish if a cell is homo- or heterozygous for a mutation as well as their relative expression levels. We have validated this system for single cell analysis using lung cancer cell lines with known L858R and T790M mutation status. We present initial findings of EGFR mutation screening of lung CTCs from patients with known EGFR status based on tissue profiling. By tracking patients over time, comparing the CTC profiles, and correlating it to patient outcomes, we may be able to better identify early treatment resistant clones and adjust their treatment to improve patient outcome. Citation Format: Sarah Owen, Ting-Wen Lo, Shamileh Fouladdel, Ebrahim Azizi, Nithya Ramnath, Sunitha Nagrath. Gene expression and mutation profiles of single lung circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 407.

Abstract LB-238: Characterization of circulating tumor cells and its PD-L1 expression with high-sensitivity liquid biopsy panel in non-small cell lung cancer patients

Abstract Early detection and intervention are crucial for long-term survival of either primary or recurrent lung cancer patients. Circulating tumor cells (CTCs) could be powerful biomarkers for the diagnosis, prognosis, and treatment planning of cancer. In this work we applied our FAST cytometer, a fiber-optic array scanning technology (FAST) to develop a sensitive diagnostic blood tests (“liquid biopsies”) for NSCLC. This technology is based on the ultra-rapid, sensitive and accurate detection of rare circulating cells expressing the biomarker(s) of interest. By applying the FAST cytometer with a unique NSCLC specific cocktail, we were able to detect CTC in NSCLC setting with higher sensitivity as compared with traditional cytokeratin-based detection. In a pilot cohort of 51 NSCLS patients, we have detected CTC in 74.2% using our unique panel for NSCLC CTC, this has raised our sensitivity from 48.8% using traditional cytokeratin-based detection. In addition, we have also interrogated circulating cancer associated fibroblasts (cCAF) as an additional liquid biopsy marker for NSCLC. We detected cCAF in 67% NSCLC patients. When combined with our enhanced CTC detection method, addition of cCAF further increased our sensitivity to 88.5%. Moreover, using clinically validated PD-L1 antibody (Ventana SP263) as reference, we have demonstrated our capacity to analyze PD-L1 expression on CTC at protein level, we have shown detection of PD-L1+ CTC in 80% of the patients. To summarize, we have developed an unique panel to detect CTC with higher sensitivity using combinational detection and we have demonstrated that by combining CTC detection with cCAF detection, liquid biopsy sensitivity for cancer detection can be further increased without significant increase in false positive rates. Lastly, we developed a method to analyze the PD-L1 expression on CTC using clinically validated Ventana PD-L1 (SP263) rabbit monoclonal antibody as reference which can potentially serve as a companion diagnostics tool for NSCLC immunotherapy Citation Format: Xiaohe Liu, Zheng Ao, Jordan S. Preiss, Joel Neal, Lisa Ya Zhou, Lidia Sambucetti, Heather A. Wakelee. Characterization of circulating tumor cells and its PD-L1 expression with high-sensitivity liquid biopsy panel in non-small cell lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-238.

Abstract 3393: Altered immune response in the transcriptome of patients with lung cancer

Abstract Introduction The immune system is critical to surveying and eradicating abnormal cells, but tumor cells develop ways to escape immunosurveillance and induce an immunosuppressive state. We previously developed and validated gene expression (GE) signatures measured in the normal airway-epithelial brushings in patients undergoing bronchoscopy for suspicion of lung cancer (LC). In this study, we seek to understand if the immunosuppressive environment extends to the airway field of injury via profiling of endobronchial biopsies from the central airway containing a broader range of cell types, including immune cells. Methods Endobronchial biopsies from normal-appearing regions of the central airway were collected from ever smokers undergoing workup of indeterminate pulmonary nodules (7-30 mm in diameter) suspicious for LC at military and VA hospitals within the DECAMP consortium. Initially, total RNA from the biopsies (n=44, discovery-set) were isolated and sequenced. Reads were aligned to hg19 using STAR and gene level counts were quantified with RSEM. Poor quality samples were removed using FASTQC and RSEQC. Differential GE associated with cancer status was identified using edgeR, adjusting for smoking-status, COPD and sample quality. RNA from additional endobronchial biopsies (n=49, validation-set) were isolated and preprocessed similarly. Genes differentially expressed with LC status in the discovery-set were tested in the validation-set using gene set variation analysis (GSVA). Functional enrichment of cancer associated genes was explored using Enrichr. Comparison of cancer signatures identified in previously published LC studies was investigated using GSEA. CIBERSORT, xCell, TIMER software and single-cell RNA sequencing data generated from airway brushings were used to deconvolute the immune cell content of the bulk biopsy samples. Results We identified a GE signature associated with LC which was significantly and concordantly enriched in the validation set of biopsies and two previously published studies of LC-associated GE in airway brushings. Genes decreased in LC patient biopsies were enriched for genes involved in immune-related pathways, including cytokine interactions, the inflammatory response and neutrophil degranulation. Computational deconvolution and comparison with single-cell RNAseq data predicts a decrease in neutrophils in the airway of LC patients. Conclusion We identified LC-associated GE alterations in smokers presenting with indeterminate pulmonary nodules. Down-regulated genes in LC subjects are strongly associated with immune system function, specifically neutrophil biology. Subjects with LC appear to have an immunosuppressive environment directed towards myeloid cell populations, and this could have implications for the future development of immunoprevention therapies. Citation Format: Kahkeshan Hijazi, Julian Lel, Ehab Billatos, Elizabeth Moses, Christopher S. Stevenson, Matthew V. Lorenzi, Gang Liu, Joshua D. Campbell, Yusuke Koga, Jiarui Zhang, Fenghai Duan, Helga Marques, Marc E. Lenburg, Avrum E. Spira, Jennifer Beane. Altered immune response in the transcriptome of patients with lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3393.

Outcomes of low-intensity biopsy surveillance for rejection in paediatric cardiac transplantation

Significant inter-centre variability in the intensity of endomyocardial biopsy surveillance for rejection following paediatric cardiac transplantation has been reported. Our aim was to determine if low-intensity biopsy surveillance with two scheduled biopsies in the first year would produce outcomes similar to published registry outcomes. A retrospective study of paediatric recipients transplanted between 2008 and 2014 using a low-intensity biopsy protocol consisting of two surveillance biopsies at 3 and 12-13 months in the first post-transplant year, then annually thereafter. Additional biopsies were performed based on echocardiographic and clinical surveillance. Excluded were recipients that were re-transplanted or multi-organ transplanted or were followed at another institution. A total of 81 recipients in the first 13 months after transplant underwent an average of 2 (SD ± 1.3) biopsies, 24 ± 6.8 echocardiograms, and 17 ± 4.4 clinic visits per recipient. During the 13-month period, 19 recipients had 24 treated rejection episodes, with the first at an average of 2.8 months post-transplant. The 3-, 12-, 36-, and 60-month conditional on discharge graft survival were 100%, 98.8%, 98.8%, and 90.4%, respectively, comparable to reported figures in major paediatric registries. At a mean follow-up of 4.7 ± 2.1 years, four patients (4.9%) developed cardiac allograft vasculopathy, three (3.7%) developed a malignancy, and seven (8.6%) suffered graft loss. Rejection surveillance with a low-intensity biopsy protocol demonstrated similar intermediate-term outcomes and safety measures as international registries up to 5 years post-transplant.

Should We Screen Oncotype DX Eligible Patients With Breast MRI?

PurposeOncotype DX is a genomic test used to predict chemotherapy benefit and recurrence risk in early stage breast cancer patients. A previous study has shown that in patients with multiple tumors sent for Oncotype DX analysis, differing results between the tumors were yielded that ultimately changed chemotherapy management in 27% of cases. The purpose of this study is to determine the utility of preoperative MRI in Oncotype DX eligible patients. MethodsA retrospective, Institutional review board approved study identified 888 consecutive new breast cancer patients from 2012 to 2016 at a single institution and identified 541 patients who potentially would be eligible for Oncotype DX. Frequency of additional disease in this population group was recorded. The method of imaging used, either conventional imaging (mammography and ultrasound) or additional MRI, was evaluated. ResultsOf 541 patients, 360 patients had conventional imaging performed only and 181 patients had an additional breast MRI. Of 541 patients, 73 patients (13.5%) had additional biopsy proven multifocal, multicentric, or contralateral tumors identified. The total number of additional disease within the conventional imaging group was 39 of 360 patients (10.8%), vs 34 of 181 patients (18.8%) in the MRI group, which was statistically significant (P = 0.02). Total 34 of 73 patients (46.6%) had additional disease only detected by MRI. ConclusionsIn patients who may be eligible for Oncotype DX evaluation, 13.5% of patients were found to have additional disease. Nearly half of the patients had additional disease only detected by MRI, indicating the potentially utility of preoperative MRI in this patient population.

Worm-Like Soft Robot for Complicated Tubular Environments.

This article describes a worm-like soft robot capable of operating in complicated tubular environments, such as the complex pipeline with different diameters, water, oil, and gas environments, or the clinical application in natural orifice transluminal endoscopic surgery. The robot is completely soft and robust, and consists of one multidegree of freedom (DoF) extension module and two clampers for locomotion and steering. The multi-DoF extension module is able to adjust the heading direction in the three-dimensional space. The clamper has a basic expansion module structure and detachable sucking module structure. The combined clamping principle for sticking to the inner wall can be reconfigurable to adapt the tubes with multiple tubular scales and super elastic materials. For fabrication of the mechanical structure, a low-cost and time-efficient method is proposed in this article. Based on our proposed robot, a series of phantom and application experiments are performed. The results demonstrate that the soft robot can freely bend and elongate with the entire soft body, and pass through tubes with changing diameters or branches, dry tubes, liquid environments, hard surfaces, and even soft deformable tubes. It has the ability to remove a load of >10 times its own weight. In addition, an additional visualization unit, biopsy, and electromagnetic sensor are mounted on the robot tip for the real-time image inspection, manipulation, and robot tracking. The proposed worm-like soft robot is compact, flexible-actuated, and sufficiently safe, as well as extensible. Its ability to move in the complex unstructured environment shows a great potential for search and medical applications.

Evaluación de la biopsia de fusión elástica vs. biopsia sistemática para la detección del cáncer de próstata: resultados de un estudio multicéntrico en 1.119 pacientes

ObjectivesTo assess the accuracy of targeted and systematic biopsies for the detection of prostate cancer (PCa) and clinically significant PCa (csPCa) in the everyday practice, evaluating the need for additional systematic biopsies at the time of targeted biopsy. Patients and methodsFrom our multicentric database gathering data on 2,115 patients who underwent fusion biopsy with Koelis™ system between 2010 and 2017, we selected 1,119 patients who received targeted biopsies (a median of 3 for each target), followed by systematic sampling of the prostate (12 to 14 cores). Overall and clinically significant cancer detection rate (CDR) of Koelis™ fusion biopsies were assessed, comparing target and systematic biopsies. Secondary endpoint was the identification of predictors of PCa detection. ResultsThe CDR of targeted biopsies only was 48% for all cancers and 33% for csPCa. The performance of additional, systematic prostate sampling improved the CDR of 15% for all cancers and of 12% for csPCa. PCa was detected in 35%, 69%, and 92% of patients with lesions scored as PI-RADS 3, 4 and 5, respectively. Elevated PI-RADS score and positive digital rectal examination were predictors of PCa, whereas biopsy-naïve status was associated with csPCa. ConclusionIn the everyday practice target biopsy with Koelis™ achieves a good CDR for all PCa and csPCa, which is significantly improved by subsequent systematic sampling of the prostate. The outstanding outcomes of fusion biopsy are confirmed also in biopsy-naïve patients. Elevated PI-RADS score and positive digital rectal examination are strongly associated with presence of PCa.

PSMA heterogeneity and DNA repair defects in prostate cancer.

5002 Background: Prostate-specific membrane antigen (PSMA) is a promising target for theranostics in metastatic castration resistant prostate cancer (mCRPC). Methods: Membranous PSMA (mPSMA) expression was immunohistochemically evaluated in castration sensitive (CSPC) (n = 38) and mCRPC (n = 60) tissue biopsies, and associations with molecular aberrations (next-generation sequencing; NGS) and clinical outcome were determined. Results: mPSMA expression was significantly higher (p = 0.005) in mCRPC biopsies (median H-score [interquartile range]; 55.0 [2.8-117.5]) compared to CSPC biopsies (17.5 [0.0-60.0]). Furthermore, patients with higher mPSMA expression ( > median H-score) at diagnosis had higher Gleason Grade (p = 0.04) and shorter OS (p = 0.006). Critically, 42% (16/38) of CSPC biopsies and 27% (16/60) of mCRPC biopsies were completely negative for mPSMA expression. In addition, CSPC and mCRPC biopsies expressing mPSMA demonstrated marked intra-tumor heterogeneity in expression levels, commonly exhibiting areas without detectable PSMA (CSPC – 100%; mCRPC – 84%), while heterogeneous mPSMA expression between metastases from the same patient was also observed. Subsequent genomic analysis showed that mCRPC patients with deleterious DNA damage repair (DDR) aberrations have higher (p = 0.016) mPSMA expression (87.5 [25.0-247.5]) than those without these (20 [0.3-98.8]). Furthermore, 9 of the 11 patients (82%) responding to PARP inhibition had a mPSMA H-Score above the median. The association between mPSMA expression and DDR aberrations was validated in an independent cohort with known DDR aberrations. Tumors with DDR aberrations had significantly higher mPSMA (ATM 212.5 [136.3-300] p = 0.005; BRCA2 300 [165-300] p = < 0.001) than unselected mCRPC biopsies (55.0 [2.75-117.5]). Finally, analyses of 122 mCRPC biopsy transcriptomes confirmed a negative correlation between PSMA and BRCA2 mRNA expression (p = 1.5x10-5). Conclusions: mPSMA expression in CSPC and mCRPC exhibits marked intra- and inter-patient heterogeneity, limiting the clinical utility of PSMA-targeted theranostics. We show for the first time that DDR gene aberrations associate with high mPSMA expression and may serve as predictive biomarkers for PSMA-targeted therapies.

Detection of alpha-synuclein aggregates in gastrointestinal biopsies by protein misfolding cyclic amplification

Lewy bodies and neurites, the pathological signatures found in the central nervous system of Parkinson's disease (PD) patients, are primarily composed of aggregated alpha-synuclein (aSyn). The observation that aSyn aggregates are also found in the enteric nervous system has prompted several studies aimed at developing a diagnostic procedure based on the detection of pathological aSyn in gastrointestinal (GI) biopsies. The existing studies, which have all used immunohistochemistry for the detection of pathological aSyn, have had conflicting results. In the current survey, we analyzed the seeding propensity of aSyn aggregates from GI biopsies.A total of 29 subjects participated to this study, 18 PD patients and 11 controls. For each patient, 2 to 4 GI biopsies were taken from the same site (antrum, sigmoid colon or rectum) and used to seed the aggregation of recombinant aSyn in an assay inspired from the protein misfolding cyclic amplification (PMCA) method. In a subset of patients and controls (14 and 3, respectively), one or two additional biopsies were analyzed by immunohistochemistry for the presence of phosphorylated aSyn histopathology (PASH) using antibodies against phosphorylated aSyn and PGP 9.5.Except for one subject, none of the control samples seeded aSyn aggregation in PMCA reaction. GI biopsies from patients with PD seeded aSyn aggregation in 10 out of 18 cases (7 from the sigmoid colon, 2 from the antrum and one from the rectum). There was good agreement between PMCA and immunohistochemistry results as, except for two cases, all PMCA-positive PD patients were also PASH-positive.Our findings show that the PMCA method we implemented is capable of detecting aSyn aggregates in routine GI biopsies. They also suggest that rectum biopsies do not contain sufficient amounts of aggregated aSyn to detect seeded assembly by PMCA. While encouraging, our findings indicate that further studies are needed to establish the diagnostic potential of the PMCA method we implemented to detect aSyn aggregates in upper GI biopsies.

Effect of Sentinel Node Biopsy in Clinically N0, BRAF V600E-Mutated, Small Papillary Thyroid Carcinoma: A Pilot Study.

BRAF V600E mutation papillary thyroid cancer (PTC) is more aggressive with a higher risk of lymph node involvement and a poorer prognosis. Prior studies failed to demonstrate the superiority of prophylactic lymphadenectomy. We investigated the utility of additional radio-guided sentinel node biopsy (SNB). We analyzed 15 patients with N0 PTC by ultrasound and BRAF mutation on preoperative biopsy treated with total thyroidectomy (TT) or TT + prophylactic central neck dissection (PCND) alone or with SNB. Conventional surgery was performed before SNB. We recorded primary tumor diameter, multifocality, extrathyroid infiltration, neoplastic emboli, and tall cell variant. At follow-up, we evaluated basal and stimulated thyroglobulin and ultrasound or radioiodine scintigraphy. Of 15 consecutive patients, 5 received conventional surgery alone, and 10 had SNB. For the first group, 4 underwent TT, and 1 had TT + PCND. Among the SNB group, 1 had no sentinel node detected and underwent a simple TT, 2 had TT + PCND+ SNB in the lateral compartment, and 7 had TT + SNB in 1 to 3 neck compartments. Micrometastases were found in 1 of 3 PCND specimens. Sentinel node biopsy revealed metastasis in 3 of 6 central compartment biopsies, in 2 of 6 biopsies in the ipsilateral lateral compartment, and in none of 2 biopsies in the contralateral compartment. Sentinel node biopsy allowed the removal of micrometastases in 4 of 10 patients. At 53 months' (mean) follow-up, no relapse was documented. Radio-guided SNB correctly and efficiently stages cN0 BRAF-mutated PTC patients. Sentinel node biopsy could limit time-consuming, risk-exposing compartmental prophylactic dissections.

Tu1023 – Additional Intestinal Mucosal Biopsy Sampling for Research Purposes is Safe During Pediatric Endoscopic Procedures

Tu1023 – Additional Intestinal Mucosal Biopsy Sampling for Research Purposes is Safe During Pediatric Endoscopic Procedures

Prostate cancer treatment with Irreversible Electroporation (IRE): Safety, efficacy and clinical experience in 471 treatments.

BackgroundIrreversible Electroporation (IRE) is a novel image-guided tissue ablation technology that induces cell death via very short but strong pulsed electric fields. IRE has been shown to have preserving properties towards vessels and nerves and the extracellular matrix. This makes IRE an ideal candidate to treat prostate cancer (PCa) where other treatment modalities frequently unselectively destroy surrounding structures inducing severe side effects like incontinence or impotence. We report the retrospective assessment of 471 IRE treatments in 429 patients of all grades and stages of PCa with 6-year maximum follow-up time.Material and findingsThe patient cohort consisted of low (25), intermediate (88) and high-risk cancers (312). All had multi-parametric magnetic resonance imaging, and 199 men had additional 3D-mapping biopsy for diagnostic work-up prior to IRE. Patients were treated either focally (123), sub-whole-gland (154), whole-gland (134) or for recurrent disease (63) after previous radical prostatectomy, radiation therapy, etc. Adverse effects were mild (19.7%), moderate (3.7%) and severe (1.4%), never life-threatening. Urinary continence was preserved in all cases. IRE-induced erectile dysfunction persisted in 3% of the evaluated cases 12 months post treatment. Mean transient IIEF-5-Score reduction was 33% within 12-month post IRE follow-up and 15% after 12 months. Recurrences within the follow-up period occurred in 10% of the treated men, 23 in or adjacent to the treatment field and 18 outside the treatment field (residuals). Including residuals for worst case analysis, Kaplan Maier estimation on recurrence rate at 5 years resulted in 5.6% (CI95: 1.8–16.93) for Gleason 6, 14.6% (CI95: 8.8–23.7) for Gleason 7 and 39.5% (CI95: 23.5–61.4) for Gleason 8–10.ConclusionThe results indicate comparable efficacy of IRE to standard radical prostatectomy in terms of 5-year recurrence rates and better preservation of urogenital function, proving the safety and suitability of IRE for PCa treatment. The data also shows that IRE, besides focal therapy of early PCa, can also be used for whole-gland ablations, in patients with recurrent PCa, and as a problem-solver for local tumor control in T4-cancers not amenable to surgery and radiation therapy anymore.

Feasibility and clinical utility of endoscopic ultrasound guided biopsy of pancreatic cancer for next-generation molecular profiling.

Next-generation sequencing is enabling molecularly guided therapy for many cancer types, yet failure rates remain relatively high in pancreatic cancer (PC). The aim of this study is to investigate the feasibility of genomic profiling using endoscopic ultrasound (EUS) biopsy samples to facilitate personalised therapy for PC. Ninty-five patients underwent additional research biopsies at the time of diagnostic EUS. Diagnostic formalin-fixed (FFPE) and fresh frozen EUS samples underwent DNA extraction, quantification and targeted gene sequencing. Whole genome (WGS) and RNA sequencing was performed as proof of concept. Only 2 patients (2%) with a diagnosis of PC had insufficient material for targeted sequencing in both FFPE and frozen specimens. Targeted panel sequencing (n=54) revealed mutations in PC genes (KRAS, GNAS, TP53, CDKN2A, SMAD4) in patients with histological evidence of PC, including potentially actionable mutations (BRCA1, BRCA2, ATM, BRAF). WGS (n=5) of EUS samples revealed mutational signatures that are potential biomarkers of therapeutic responsiveness. RNA sequencing (n=35) segregated patients into clinically relevant molecular subtypes based on transcriptome. Integrated multi-omic analysis of PC using standard EUS guided biopsies offers clinical utility to guide personalized therapy and study the molecular pathology in all patients with PC.

A Multicentre Analysis of the Detection of Clinically Significant Prostate Cancer Following Transperineal Image-fusion Targeted and Nontargeted Systematic Prostate Biopsy in Men at Risk

BackgroundProstate biopsy guided by magnetic resonance imaging (MRI) is increasingly used to obtain tissue from men with suspected prostate cancer (PC). ObjectiveTo report a multicentre series of image-fusion transperineal prostate biopsies and compare the diagnostic yield of clinically significant PC (csPC) between targeted and nontargeted biopsies. Design, setting, and participantsThe study included 640 consecutive patients with elevated prostate specific antigen (PSA) presenting for first biopsy or following a previous negative transrectal biopsy under the care of 13 urologists in 11 centres in the UK (April 2014–June 2017). InterventionMultiparametric MRI was carried out in 61 approved prostate MRI centres with transperineal targeted alone (n=283) or targeted plus nontargeted (n=357) transperineal rigid image-fusion targeted biopsy (MIM-Symphony-DX). Outcome measurements and statistical analysisRates of csPC and insignificant cancer detection in targeted and nontargeted biopsies were measured using a number of thresholds to define clinical significance. The primary definition was Gleason≥4+3 or any grade ≥6mm. Results and limitationsThe mean age, median PSA, and median prostate volume for the cohort were 63.8yr (standard deviation [SD] 8.4), 6.3 ng/ml (SD 5.8), and 42.0cm3 (SD 24.7), respectively. Overall, 276/640 men (43.1%) were diagnosed with csPC. csPC was detected from targeted biopsies alone in 263/640 cases (41.1%). Of the 357 men who underwent nontargeted biopsies, three (0.8%) had csPC exclusively in nontargeted cores, with no evidence of cancer in targeted cores. Overall, 32/357 (9.0%) had csPC in nontargeted biopsies regardless of the targeted biopsy findings. Clinically insignificant disease in nontargeted biopsies was detected in 93/357 men (26.1%). Our findings were consistent across all other thresholds of clinical significance. Limitations include the lack of nontargeted biopsies in all men. ConclusionsIn this large multicentre series, nontargeted prostate biopsy cores had a low yield of csPC and a high yield of clinically insignificant PC. An image-fusion targeted-biopsy-only approach maintains high detection for csPC and low detection of clinically insignificant cancers. Patient summaryIn this report, we found that following prostate multiparametric magnetic resonance imaging and targeted transperineal biopsies of suspicious areas, the clinical value of performing additional extensive unguided biopsies of nonsuspicious areas is limited and can often find insignificant cancers that do not need treatment.

Ammonium tetrathiomolybdate treatment of copper-associated hepatopathy in dogs.

BackgroundCopper‐associated hepatopathy (CAH) is a common cause of liver disease in dogs. Although d‐penicillamine can be an effective treatment, some dogs fail treatment or develop adverse effects. Ammonium tetrathiomolybdate (TTM) has been used to treat pathologic copper accumulation in other species, but its therapeutic potential for CAH is unknown.ObjectivesTo investigate short‐term safety and efficacy of TTM for treatment of CAH.AnimalsTen dogs with CAH.MethodsProspective study. All dogs were treated with TTM PO for 6 weeks, and hepatic biopsies were performed after the treatment course. Dog experiencing initial decreases in hepatic copper concentrations ([Cu]H) received 6 additional weeks of TTM treatment and underwent 1 additional biopsy. Physical and laboratory examinations were performed every 2 weeks for study duration.ResultsEight of 10 dogs had decreases in [Cu]H. Compared to baseline (median, 1606 μg/g; range, 572‐5158 μg/g), [Cu]H were decreased at 6 weeks (1033 μg/g, 450‐2975 μg/g; P = .04) and 12 weeks (931 μg/g, 218‐1677 μg/g; P = .02). Hepatic molybdenum concentrations increased >50‐fold (P < 0.001). Changes in histologic scores and hematologic and biochemical test results were variable and not significantly different from baseline. One dog developed presumed immune‐mediated anemia and thrombocytopenia, but it was unclear if this was related to TTM administration.Conclusions and Clinical ImportanceResults suggest that TTM can effectively decrease [Cu]H in some dogs with CAH. Larger studies are needed to determine the overall safety and efficacy of TTM for treating CAH and how it compares with current treatments.

Validation of immunohistochemical tests performed on cytology cell block material: Practical application of the College of American Pathologists' guidelines.

The advent of fiberoptic endoscopy with biopsy has revolutionized procurement of specimens from deep sites. This has translated into more cytologic specimens whereby the material is limited and best handled by cytology laboratory staff. While the diagnosis of the pathologic process is of utmost importance, there is increasing expectation that the diagnosis be specific and accurate as not to require additional biopsy for initiation of treatment. This expectation has driven demand in immunohistochemical (IHC) and molecular studies conducted specifically on material processed as cytology specimens. The Clinical Laboratory Improvement Amendments of 1988 requires laboratories in the United States of America to verify the performance of patient tests. Due to varying laboratory practices with respect to validation of IHC assays, the College of American Pathologists introduced guidelines for analytic validation of IHC tests. These guidelines address how to perform validation by recommending the number of cases in the validation set, comparator concordance, and when to revalidate. The main thrust of the guidelines is based on formalin-fixed paraffin-embedded tissue with only one expert consensus opinion referring to validation of IHC tests on cytology specimens which delegates to the medical director, the determination of number of positive and negative cases to be tested. This article will outline how an academic center approaches validation of IHC studies performed on cytology cell block specimens using the College of American Pathologists guidelines. A stepwise approach from selection of antibodies to validate followed by building the validation panel and evaluating the stain results for concordance against the gold standard of histology tissue specimen will be described. A rationale for dealing with discordant results and future innovations will conclude the report.

MRI-based prostate specific antigen density predicts Gleason score upgrade in an active surveillance cohort.

107 Background: Elevated prostate specific antigen density (PSAD) based on transrectal ultrasound (TRUS) measurements has been shown to be strongly associated with clinically significant disease and to predict progression on active surveillance for men with low stage/grade disease. We hypothesize that elevated MRI PSAD is similarly associated with increased risk of progression on subsequent biopsy. Methods: Patients with Gleason grade 3+3 on diagnostic transrectal ultrasound-guided biopsy who were managed with active surveillance and underwent at least one additional biopsy were included. Patients who underwent MRI greater than 6 months after diagnosis were excluded. Summary statistics were generated for demographic and clinical characteristics. MRI PSAD was calculated using prostate volume on MRI and PSA temporally closest to the MRI. Multivariable logistics regression models were used to evaluate the association between MRI PSAD and predictors of upgrade on serial biopsy. Results: 166 patients were included in the study. Of these patients, 74 of them were upgraded to Gleason grade ≥7 on follow up biopsy. TRUS volume was noted be strongly correlated with MRI prostate volume (Pearson’s r=0.82, p&lt;0.01). MRI PSAD 0.15-0.225 ng/ccl and ≥0.0225 ng/cc were significantly associated with upgrade to Gleason grade 7 compared to MRI PSAD &lt;0.075 ng/ml/ml after controlling for age and time since diagnosis. MRI PSAD less than 0.15 was not associated with upgrade on follow up biopsy (in any patient, if so, state that no one with a PSAD &lt; 0.15 upgraded). Conclusions: MRI PSAD is significantly associated with Gleason upgrading on follow up biopsy for men initially diagnosed with Gleason grade 3+3 disease. This finding is important because surveillance MRI is increasingly being used to monitor men on active surveillance.

Should we look for Hirschsprung disease in all children with meconium plug syndrome?

BackgroundMeconium plug syndrome (MPS) is associated with Hirschsprung disease (HD) in 13–38% of cases. This study sought to assess institutional variation in utilization of rectal biopsy in children with MPS and the likelihood of diagnosing HD in this population. MethodsPatients with MPS on contrast enema in the first 30 days of life from the Pediatric Health Information System database in 2016–2017 were included. Institutional rates of rectal biopsies performed during the initial admission were calculated and then used to predict institutional rates of early HD diagnoses using Poisson regression. ResultsOf 373 newborns with MPS, 106 (28.4%) underwent early rectal biopsy, of whom 43 (40.5%) had HD. Fifty-seven (15.3%) were ultimately diagnosed with HD. Eight (14%) of these patients had a delayed diagnosis. HD rates between institutions did not differ significantly (range 0–50%, p=0.52), but usage of early rectal biopsy did (range 0–80%, p=0.03). Each additional early biopsy increased the early HD diagnosis rate by 35% (β=0.30, 95% CI 0.15–0.45, p<0.0001). ConclusionThe incidence of HD is increased in children with MPS. There is significant hospital variability in the utilization of early rectal biopsy, and opportunity exists to standardize practice.Type of Study: Study of Diagnostic testLevel of Evidence: Level III