Successful Biopsy Research Articles

Preliminary investigation: Feasibility study of a virtual reality breast biopsy simulation

Rationale and ObjectivesUltrasound-guided breast biopsies are the most frequently performed imaging-guided breast procedures. During training, learners may lack exposure due to limited volume and sensitive anatomy. Current simulation training often involves the use of manufactured or homemade (chicken or turkey breast) phantoms. Virtual reality is an emerging technology, allowing learners to have flexibility in learning, real-life interactive experiences and measurable feedback. The purpose of this study is to assess the feasibility of a novel virtual reality breast biopsy simulation trainer. MethodsThis was a HIPAA-compliant, IRB-approved prospective feasibility study. The participants were three fellowship-trained breast radiologists with varying years of experience. Participants received an introduction to the virtual reality (VR) breast biopsy simulation and brief training session, describing how to enter the simulation and navigate controls. The participants were instructed to perform as many breast biopsies as possible within a 15-min time period. One biopsy cycle consisted of entering the breast with the biopsy needle, taking a biopsy sample and removing the needle. Time to successfully biopsy the mass was recorded by the VR program, and this data was recorded to assess improvement from start to finish of the simulation. A post-procedure survey was administered to all participants immediately after completion of the simulation. Qualitative open-ended subjective feedback was also obtained via Qualtrics. ResultsAll three breast radiologists completed the simulation. There were no complications from the procedure, including no motion sickness or fatigue resulting in simulation termination. Results of data obtained from the simulation showed decreased time to successful biopsy (slope = -19.23) with each subsequent trial for all three participant breast radiologists. A decreased time to biopsy was associated with a higher cumulative number of successful biopsies (p = 0.0037). A higher number of cumulative successful biopsies was associated with decreased number of body entries (p = 0.0332) and biopsy fires (p = 0.0221) before a successful tissue sample. Mean responses for Likert scale survey results were overall high. The radiologists found the simulator to be engaging (4.67/5.00 ± 0.47), realistic (2.67/3.00 ± 0.47) and would recommend the simulation to other healthcare professionals (2.67/3.00 ± 0.47). The radiologists participating in the trial also provided overall favorable subjective feedback. ConclusionsThis study presents a novel approach for ultrasound-guided breast biopsy training with a VR simulation that showed to be successfully capable of recording time-to-completion of each biopsy attempt. Future studies will be directed toward assessing the utility of the simulation in improving trainee skills.

Percutaneous Disc Biopsy versus Bone Biopsy for the Identification of Infectious Agents in Osteomyelitis/Discitis

PurposeTo determine whether sampling of the disc or bone is more likely to yield positive tissue culture results in patients with vertebral discitis and osteomyelitis (VDO). Materials and MethodsRetrospective review was performed of consecutive patients who underwent vertebral disc or vertebral body biopsy at a single institution between February 2019 and May 2023. Inclusion criteria were age ≥18 years, presumed VDO on spinal magnetic resonance (MR) imaging, absence of paraspinal abscess, and technically successful percutaneous biopsy with fluoroscopic guidance. The primary outcome was a positive biopsy culture result, and secondary outcomes included complications such as nerve injury and segmental artery injury. ResultsSixty-six patients met the inclusion criteria; 36 patients (55%) underwent disc biopsy, and 30 patients (45%) underwent bone biopsy. Six patients required a repeat biopsy for an initially negative culture result. No significant demographic, laboratory, antibiotic administration, or pain medication use differences were observed between the 2 groups. Patients who underwent bone biopsy were more likely to have a history of intravenous drug use (26.7%) compared with patients who underwent disc biopsy (5.5%; P = .017). Positive tissue culture results were observed in 41% of patients who underwent disc biopsy and 15% of patients who underwent bone biopsy (P = .016). No vessel or nerve injuries were detected after procedure in either group. ConclusionsPercutaneous disc biopsy is more likely to yield a positive tissue culture result than vertebral body biopsy in patients with VDO.

Image-guided orbital surgery: a preclinical validation study using a high-resolution physical model

ObjectivePreclinical validation study to assess the feasibility and accuracy of electromagnetic image-guided systems (EM-IGS) in orbital surgery using high-fidelity physical orbital anatomy simulators.MethodsEM-IGS platform, clinical software, navigation instruments and reference...

Successful cholangioscopy-guided biopsy using a novel thin cholangioscope under balloon enteroscopy in a patient with Roux-en-Y gastrectomy.

Successful cholangioscopy-guided biopsy using a novel thin cholangioscope under balloon enteroscopy in a patient with Roux-en-Y gastrectomy.

Ultrasound Guided Phrenic Nerve Block for Percutaneous Computer Tomography Guided Lung Biopsy

Abstract The aim of this paper is to present the technique of the ultrasound (US) guided phrenic nerve block (PNB). This is an important adjuvant technique for percutaneous computer-tomography (CT) lung biopsy of nodules situated in the lower lobes, in proximity of the diaphragm, with a diameter of less than 2 cm. These types of nodules have a high location variability during respiration, which makes them hard to be approached for a successful biopsy. US visualization of the nerve is possible after identifying specific landmarks as the sternocleidomastoid and scalene muscle, interval jugular vein and brachial plexus. The phrenic nerve is seen as an oval hypoechogenic structure with no Doppler signal, superficial to the anterior scalene muscle. Ropivacaine can be used as a local anesthetic to induce the PNB. Results: Success of the phrenic nerve block can be assessed by CT scanogram, which shows the ipsilateral hemidiaphragm elevated, and by subsequent lung scans that show little to no location variability of the target lesion. Conclusion. US-guided PNB is a safe and efficient procedure that can help during percutaneous CT-guided lung biopsy of small basal nodules.

Deep learning performance on MRI prostate gland segmentation: evaluation of two commercially available algorithms compared with an expert radiologist.

Accurate whole-gland prostate segmentation is crucial for successful ultrasound-MRI fusion biopsy, focal cancer treatment, and radiation therapy techniques. Commercially available artificial intelligence (AI) models, using deep learning algorithms (DLAs) for prostate gland segmentation, are rapidly increasing in numbers. Typically, their performance in a true clinical context is scarcely examined or published. We used a heterogenous clinical MRI dataset in this study aiming to contribute to validation of AI-models. We included 123 patients in this retrospective multicenter (7 hospitals), multiscanner (8 scanners, 2 vendors, 1.5T and 3T) study comparing prostate contour assessment by 2 commercially available Food and Drug Association (FDA)-cleared and CE-marked algorithms (DLA1 and DLA2) using an expert radiologist's manual contours as a reference standard (RSexp) in this clinical heterogeneous MRI dataset. No in-house training of the DLAs was performed before testing. Several methods for comparing segmentation overlap were used, the Dice similarity coefficient (DSC) being the most important. The DSC mean and standard deviation for DLA1 versus the radiologist reference standard (RSexp) was and for DLA2 versus RSexp it was . A paired -test to compare the DSC for DLA1 and DLA2 showed no statistically significant difference (). Two commercially available DL algorithms (FDA-cleared and CE-marked) can perform accurate whole-gland prostate segmentation on a par with expert radiologist manual planimetry on a real-world clinical dataset. Implementing AI models in the clinical routine may free up time that can be better invested in complex work tasks, adding more patient value.

Pediatric Brainstem Tumor Biopsy: Surgical Planning and Execution for Maximal Safety and Tissue Yield.

Brainstem tumors account for 10-20% of pediatric brain tumors with a peak age of diagnosis between 7 and 9years old and are often fatal. Historically, diagnosis of brainstem tumors has been largely based on imaging; however, recent studies have demonstrated the incongruities between preoperative MRI diagnosis and postoperative pathological findings highlighting the importance of brainstem biopsy for diagnostic accuracy. Stereotactic brainstem biopsy for pediatric brainstem tumors has been proven to be safe with a high diagnostic yield (96.1-97.4%) and relatively low morbidity and mortality. Successful pediatric brainstem tumor biopsy demands intricate knowledge of brainstem anatomy, cranial nerves and vasculature, and common pediatric brainstem tumors by the performing surgeon. Additionally, understanding of the surgical indications and techniques (e.g., frame-based versus frameless, robotic assistance, surgical approach, and targets selection) helps to ensure maximal safety and tissue yield. Pediatric brainstem biopsy permits histological conformation of brainstem lesions leading to accurate diagnosis and the potential for personalized treatment and future therapeutic research.

Multiparametric bone MRI targeting aides lesion selection for CT-guided sclerotic bone biopsies in metastatic castrate resistant prostate cancer

BackgroundBone biopsies in metastatic castrate-resistant prostate cancer (mCRPC) patients can be challenging. This study’s objective was to prospectively validate a multiparametric bone MRI (mpBMRI) algorithm to facilitate target lesion selection in mCRPC patients with sclerotic bone disease for subsequent CT-guided bone biopsies.Methods20 CT-guided bone biopsies were prospectively performed between 02/2021 and 11/2021 in 17 mCRPC patients with only sclerotic bone disease. Biopsy targets were selected based on MRI, including diffusion-weighted (DWI) and T1-weighted VIBE Dixon MR images, allowing for calculation of the apparent diffusion coefficient (ADC) and the relative fat-fraction (rFF), respectively. Bone marrow with high DWI signal, ADC < 1100 µm2/s and rFF < 20% was the preferred biopsy target. Tumor content and NGS-feasibility was assessed by a pathologist. Prognostic routine laboratory blood parameters, target lesion size, biopsy tract length, visual CT density, means of HU, ADC and rFF were compared between successful and unsuccessful biopsies (p < 0.05 = significant).ResultsOverall, 17/20 (85%) biopsies were tumor-positive and next-generation genomic sequencing (NGS) was feasible in 13/18 (72%) evaluated samples. Neither laboratory parameters, diameter, tract length nor visual CT density grading showed significant differences between a positive versus negative or NGS feasible versus non-feasible biopsy results (each p > 0.137). Lesion mean HU was 387 ± 187 HU in NGS feasible and 493 ± 218 HU in non-feasible biopsies (p = 0.521). For targets fulfilling all MRI selection algorithm criteria, 13/14 (93%) biopsies were tumor-positive and 10/12 (83%) provided NGS adequate tissue.ConclusionsMultiparametric bone MRI can facilitate target lesion selection for subsequent CT-guided bone biopsy in mCPRC patients with sclerotic metastases.Trial registrationCommittee for Clinical Research of the Royal Marsden Hospital registration number SE1220.

Successful Forceps Biopsy of Carcinoma of the Distal Bile Duct Under Direct Visualization Using a Stone Retrieval Balloon Catheter

Successful Forceps Biopsy of Carcinoma of the Distal Bile Duct Under Direct Visualization Using a Stone Retrieval Balloon Catheter

Factors affecting the success of CT-guided core biopsy of musculoskeletal lesions with a 13-G needle

ObjectiveTo determine the value of CT-guided bone core biopsy and investigate factors that affect diagnostic yield and biopsy outcome.Materials and methodsThe single-centre retrospective analysis included 447 patients who had CT-guided core biopsy with a 13-G needle (Bonopty®) from January 2016 to December 2021. Histological results or ≥ 6 months of clinical and radiological follow-up served as outcome references. A successful biopsy was classified as “diagnostic” when a definitive diagnosis was made and “adequate” when only the malignant or benign nature of the tumour could be determined. Biopsies were “nondiagnostic” when the nature of the lesion could not be determined. The occult lesions were defined as not seen on CT but visible on other modalities.ResultsIn 275 (62%) females and 172 (38%) males, the overall success rate was 85% (383 biopsies), with 314 (70%) diagnostic biopsies and 69 (15%) adequate biopsies. There was no relationship between biopsy success and the localisation of the lesion, length of biopsy material, or number of biopsy attempts. The lesions’ nature had a statistically significant effect on biopsy success with lytic and mixed lesions having the highest success rate. Occult lesions had the lowest success rate.ConclusionCT-guided bone core biopsy is an effective method in the workup of musculoskeletal diseases with the highest success rate in lytic and mixed lesions. No apparent relationship was found between biopsy success and biopsy length, number of attempts, or localisation of the lesion.

SAT575 Can We Miss Diagnosis Of Tall Cell Variant Papillary Thyroid Carcinoma?

Abstract Disclosure: J. Huynh: None. A. Makawi: None. G. Elshimy: None. Introduction Large thyroid nodules have a high rate of evolving into malignancy. Fine needle aspiration biopsy (FNAB) is a key diagnostic tool with a caveat of a high false-negative rate for cancer detection ranging from 0.7 to 13%. Key to maximizing the odds of a successful FNAB are the utilization of ultrasound (US) guidance, visualization of the needle tip, preprocedural consideration of the size of the target nodule, and expertise of the cytopathologist. Case presentation 40-year-old African American female who presented to endocrinology clinic given concern for a large left-side thyroid nodule with tracheal deviation seen on a CT scan of the chest. The US revealed a large left hypoechoic, spongiform nodule &amp;gt;5cm with grade 2 vascularity with no calcification measuring 5.1 x 4.3 cm. The thyroid labs were within normal range and she denied any compressive symptoms. FNAB of the nodule showed benign colloid. Given the large size of the nodule, we recommended surgical resection but the patient declined and preferred conservative management. Five months later, she started to experience dysphagia with positional neck pain and shortness of breath. Due to the progression of the compressive signs, the patient opted for left thyroidectomy which revealed multifocal papillary thyroid carcinoma (PTC) tall cell variant (TCV) with the largest foci of 1.7 cm with extrathyroidal extension and vascular invasion. She then underwent completion thyroidectomy followed by postoperative radioactive iodine ablation later on as the second surgery pathology was also consistent with PTC with metastasis to the lymph nodes. She was treated with levothyroxine with the goal to suppress TSH. Postoperatively, the patient is being monitored with biochemical testing and imaging for recurrence given the aggressive nature of her disease. Discussion There is a positive correlation between nodule size and false negative results (FNR). FNR for malignancy is known to be higher in nodules larger than 4cm. Patients with large thyroid nodules causing compressive signs should undergo resection regardless of the FNAB result. This patient had a benign FNAB initially which was misleading as the pathology of thyroidectomy was consistent with TCV PTC, a more aggressive variant. TCV PTC usually presents in larger nodules and with a higher rate of extrathyroidal extension and metastasis compared to classic. The prognosis is poorer with TCV, even without an extranodal extension. This patient received appropriate treatment with total thyroidectomy, THR therapy, sequential imaging, and biochemical testing for recurrence. A key takeaway here is that FNABs may not always reflect accurate histology of the whole lesion with larger nodules having a higher tendency for inadequate sampling. Key to successful biopsy and reducing FNAB false-negative results is an experienced radiologist, a cytopathologist familiar with these tumors, and US guidance. Presentation: Saturday, June 17, 2023

Success of Liquid Tumor Biopsy in Men with Metastatic Prostate Cancer According to Self-Identified Race.

Liquid biopsy using cell-free DNA (cfDNA) is increasingly used to identify somatic prostate cancer (PrCa) alterations when tissue biopsy of a metastatic lesion is infeasible or impractical. High-risk somatic alterations identified by cfDNA have been recently shown to predict the benefit of metastasis-directed therapy with stereotactic body radiation therapy in PrCa. However, given the older age of PrCa patients, liquid biopsy is often contaminated with alterations related to clonal hematopoiesis of indeterminate potential (CHIP), generating uncertainty in the clinical utility of the results. Given the higher incidence and aggressiveness of metastatic PrCa in Black men, we sought to determine if the success of cfDNA testing varied by race in a large and diverse cohort of United States Veterans with metastatic PrCa, hypothesizing that race would not influence the success of cfDNA testing. Veterans with metastatic PrCa underwent next-generation sequencing of cfDNA biopsy specimens through the VA National Precision Oncology Program from February 2019 to November 2022. Successful identification of PrCa with cfDNA testing was defined as the identification of an alteration in one or more PrCa-related related genes in the gene panel tested (AR, CDK12, SPOP, MED12, CCND1, BRAF, AKT1, TMPRSS2, ERG, ETV1, and ETV4). Univariate logistic regression was employed to explore the association between patient self-identified race, as well as other patient and disease-specific factors at the time of cfDNA biopsy, with the likelihood of yielding a successful cfDNA biopsy result. A total of 2066 cfDNA tests from 1985 Veterans were related to a diagnosis of PrCa, passed quality control measures, and were linkable to patient-level demographics. Median age at testing was 74, median PSA at testing was 22.7, median PSA doubling time (PSADT) was 3.6 months, and median Gleason score was 8. 57% of Veterans self-identified as White, 33% as Black, and 10% as Other. Eight hundred fourteen (39%) tests were deemed successful by finding a PrCa related gene alteration. Among successful tests, the most frequently encountered alterations were AR alterations in 60.4% White men and 33.9% Black men (p = 0.72), followed by TMPRSS2 alterations in 70.3% White men and 22.0% Black men (p<0.001). Despite a lower rate of PrCa-specific alterations in Black men, on univariate analysis, Veteran self-identified race was not associated with successful cfDNA testing (OR 0.95, 95% CI 0.78-1.14, p = 0.6), whereas PSA in quintiles 2-4, PSADT <12 months, and unit increase in Gleason score were associated with successful cfDNA testing (p<0.01 for all). Successful cfDNA biopsy in metastatic PrCa is associated with PSA and PSADT, but not related to patient self-identified race. In appropriate clinical scenarios, patients who self-identify as Black or White are equally likely to have PrCa-specific alterations detected on cfDNA testing when evaluating metastatic PrCa patients for local and systemic therapies.

Efficacy of Single-Fraction Postoperative Radiotherapy in Resected, Early-Stage Merkel Cell Carcinoma with High-Risk Features

Merkel cell carcinoma (MCC) is an aggressive skin cancer with a high recurrence risk. Postoperative radiotherapy (PORT) improves the local recurrence rate (LRR) in early-stage MCC with risk factors per NCCN guidelines: primary tumor size > 1cm, head/neck (HN) location, immunosuppression, lymphovascular invasion (LVI), and positive/narrow surgical margins. Conventionally fractionated PORT (C-PORT, ∼50 Gy in 25 fractions) is often recommended for localized MCC with these risk factors; however, some institutions elect observation. Prior studies suggest LRR of ∼20% for stage I/II MCC with high-risk features managed with surgery alone. C-PORT significantly decreases LRR but may cause significant morbidity and financial toxicity. We have previously reported that single fraction (SF)-PORT with 8 Gy achieves high rates of in-field control both in the metastatic and adjuvant settings with minimal morbidity. Here, we present updated long-term outcomes of SF-PORT, offered as an alternative to C-PORT with the hypothesis that it improves LRR relative to observation while minimizing toxicity, for resected stage I/II MCC. A retrospective, single-institution analysis was completed for stage I/II MCC patients receiving SF-PORT following surgical management. The primary objective was estimating the LRR, defined as recurrence within 2 cm of the primary tumor. Patients with resected, stage I/II MCC with at least one high-risk feature were offered C-PORT as standard of care or SF-PORT as an alternative. Forty-six patients (median age: 74.5; range 50-96 years) received SF-PORT to the primary tumor site at a median 44 days after wide local excision (85%), shave/excisional biopsy (13%), or Mohs (2%). Fifty-four percent of patients had 1 high-risk feature, 35% had 2, and 11% had 3 or more. HN (74%) was the most common primary site, 26% of tumors were > 1cm, 26% were LVI+, and 15% of patients were immunosuppressed (pathological margin status was often not available). There were no local recurrences (LRR = 0%) at a median follow-up time of 2.3 years. In-field locoregional control was 96% (44/46 patients) with 2 in-field, regional recurrences observed in draining nodal basins of HN primary lesions. There were 2 out-of-field regional nodal recurrences (1 patient with IMS; neither received elective nodal SFRT). Of 9 patients who received elective nodal SF-PORT, 8 did not have a successful sentinel lymph node biopsy. No MCC-specific deaths were observed. The most common side effect was in-field, grade 1 erythema (13%); no side effects > grade 1 (CTCAE v5) were noted. SF-PORT is associated with a very low LRR which has proven durable with long-term follow-up. The LRR for SF-PORT appears lower than historical controls treated with surgery alone for patients with resected, stage I/II MCC with high-risk features.

Contrast-enhanced ultrasound guided core needle biopsy for soft tissue tumors: Accuracy and applicability

ObjectiveTo evaluate the effectiveness of contrast-enhanced ultrasound (CEUS) guided core needle biopsy (CNB) in diagnosing soft tissue tumors (STTs) and to identify the conventional ultrasonography (US) features of STTs that are recommended for CEUS-guided CNB. Materials and methodsA retrospective study was conducted on 123 patients with surgically confirmed STTs. Before surgeries, all subjects underwent CNB under the guidance of US or CEUS. The histopathological results of surgical specimens were considered as the gold standards. A successful biopsy diagnosis was defined as the pathological subtypes obtained by biopsy consistent with the gold standard. The diagnostic yields were compared between the US and CEUS groups, and the diagnostic yields based on various conventional US features of STTs were also compared between the two groups. ResultsSixty-seven cases underwent US-guided CNB and fifty-six cases underwent CEUS-guided CNB. The clinical, biopsy, and conventional US characteristics revealed no significant difference between the two groups. The diagnostic yield of the CEUS group was statistically higher than that of the US group (p = 0.011). In the CEUS group, more STTs with the anechoic areas were identified after CEUS examination (p = 0.031). Furthermore, the diagnostic yields based on the conventional US features of STTs, including deep fascia layer (p = 0.010), a maximum diameter ≥5 cm (p = 0.037), rough margin (p = 0.016), heterogeneous echotexture (p = 0.017), and absence of anechoic area (p = 0.013), were significantly different between the two groups, and the CEUS group exhibited higher diagnostic yields. ConclusionCEUS-guided CNB was found to be an efficient method for STTs diagnosis. It is particularly recommended for STTs with the following conventional US features, including location in deep fascia layer, a maximum diameter ≥5 cm, rough margin, heterogeneous echotexture, or absence of anechoic area.

Predicting successful ultrasound-guided biopsy of liver lesions.

To determine the factors that affect successful ultrasound-guided biopsy of liver lesions and build a model predicting feasibility of US-guided liver biopsy. This is IRB-approved HIPAA-compliant retrospective review of consecutive ultrasound-guided targeted liver biopsies performed or attempted between 1/2018 and 9/2020 at a single tertiary academic institution with a total of 501 patients included. Mann-Whitney and chi-square tests were used to compare continuous and categorical variables, respectively. Logistic regression model was built to predict feasibility of successful ultrasound-guided biopsy. Liver lesion biopsy was successfully performed with US guidance in 429/501 (86%) patients. Lesions not amenable for US biopsy were smaller (median size 1.6 cm vs 3.3 cm, p < 0.0001) and deeper within the liver (median depth 9.0 cm vs 5.8 cm, p < 0.0001). The technical success rate was lowest for lesions in segment II (40/53, 75%), while lesions in segment IVb (87/91, 96%) had highest success rate (p < 0.003). US targeting in patients with 1 or 2 lesions was less feasible than in patients with 3 or more lesions, 126/180 (70%) vs. 303/321 (94%), (p < 0.0001). Model including lesion size, depth, location, and number of lesions predicts feasibility of US-guided biopsy with Area under the ROC curve (AUC) = 0.92. Linear logistic regression model that includes lesion size, depth and location, and number of lesions is highly successful in predicting feasibility of ultrasound-guided biopsy for liver lesions. Smaller lesions, deeper lesions, and lesions in segment II and VIII in patients with less than 3 lesions were less feasible for ultrasound-guided biopsy of liver lesions.

Real-time Fluorescent ICG and 99m-Tc Nanocolloid Tracer Navigation in Bilateral Sentinel Lymph Node Mapping of Vulvar Cancer

The effectiveness of sentinel lymph node (SLN) biopsy has been validated by two prospective trials, GROINS VI and GOG 1731-2. According to ESGO guideline in patients with unifocal tumors with a diameter of <4 cm, in the absence of suspected inguinal lymph nodes, SLN biopsy is recommended. The use of a radioactive tracer is mandatory.2 Using Indocyanine green (ICG) increase the detection of the vulvar sentinel node from 89.7 to 100%3. Aim of this video is to share our experience about the feasibility, safety and usefulness of the surgical identification of SLN in vulvar cancer using real-time fluorescent indocyanine green with 99m-technetium nanocolloid. Stepwise demonstration of the technique with narrated video footage. Tertiary level hospital "IRCCS Istituto Nazionale dei Tumori", Milano, Italy. A 50-year-old woman was diagnosed with vulvar cancer on biopsy of 1.5 cm size vulvar lesion under the clitoris area and referred to our Operative Unit. F-18 fluorodeoxyglucose positron-emission tomography-computed tomography (PET) showed no extra-vulvar disease. The patient was scheduled for radical vulvectomy and bilateral inguinal sentinel lymph-node biopsy (SLN). In this video the surgical procedure involved double location of SLN, first with the 99m-technetium detector followed by ICG identification. We used an ICG dilution of 2.5 mg/mL in sterile water and injected 4 mL around the tumor 5-10 min before visualization. First a handheld gamma probe used to identify the location of the SLN(s) with 99m-technetium. The fluorescence imaging was performed by the quest imaging system (FLUOPTICS©, Middenmeer, The Netherlands) that combine autofluorescence and fluorescence perfusion imaging. Second, we carried out the SLN biopsy using a dark mood procedure to identify the IGC tracer. The fluorescence imaging enables the detection of these markers through some millimeters of tissue and ICG has the advantage that is visible through the skin4. This video shows a successful combined 99m-technetium and ICG fluorescence image-guided bilateral SLN biopsy in a vulvar cancer patient using a near-infrared (NIR) optical imaging system (FLUOPTICS©). ICG for SLN mapping appears to be safe in women with vulvar cancer with a satisfactory detection rate. This may help in retaining surgical radicality while minimizing operative complications.

Clinical factors associated with successful liquid tumor biopsy in men with prostate cancer.

e13567 Background: Liquid biopsies using cell-free DNA (cfDNA) can be used in prostate cancer (PrCa) patients when tissue is unavailable and repeat biopsy is not feasible. Given the older age of PrCa patients, liquid biopsy may detect alterations related to clonal hematopoiesis of indeterminate potential (CHIP), generating uncertainty in the clinical utility of the results. We sought to identify clinical predictors of successful cfDNA biopsy, where the reported alterations are more likely to reflect the individual’s prostate cancer cfDNA instead of CHIP in a large cohort of United States Veterans with PrCa. Methods: Next-generation sequencing of cfDNA biopsy specimens was performed through the VA National Precision Oncology Program (NPOP) from February 2019 to November 2022. Successful identification of PrCa cfDNA testing was defined as the identification of an alteration in one or more PrCa-related genes included on the panel ( AR, CDK12, SPOP, MED12, CCND1, BRAF, AKT1, TMPRSS2, ERG, ETV1, and ETV4). Student’s t-tests, univariate, and multivariate logistic regression estimated significant patient and disease-specific factors at the time of cfDNA biopsy and the likelihood of obtaining a successful cfDNA biopsy result. Results: Among 5611 total cfDNA tests performed, 2066 cfDNA tests from 1985 Veterans listed PrCa as the clinical indication, passed quality control measures, and could be linked to patient-level demographics. 814 (39%) tests were deemed successful based upon identification of at least one PrCa related gene alteration. The most frequently encountered PrCa alterations were in AR (76.5%) and TMPRSS2 (22.4%). PSA was significantly higher (IQR 209.1 ng/ml) and PSA doubling time (PSADT) was significantly shorter (IQR 2.4 months) in the cohort of Veterans with successful cfDNA testing (p&lt;0.001). Among 1581 tests that reported tumor fraction, an elevated tumor fraction &gt;10 was also significantly associated with success (46.3% vs 8.1%, p&lt;0.001). On multivariate analysis, PSA elevation above 4.8 ng/ml (p&lt;0.001) and PSADT &lt;6 months (p&lt;0.001) were significantly associated with successful cfDNA testing. Actionable DDR mutations, including ATM (15.2% vs 11.7%, p=0.02), BRCA1 (1.7% vs 0.6%, p=0.03), and BRCA2 (7.4% vs 4.4%, p=0.01) were significantly more likely to be detected in a successful test compared to an unsuccessful test. Conclusions: High PSA and short PSADT are significant predictors of a cfDNA test identifying PrCa-related gene alterations in Veterans with metastatic disease instead of alterations due solely to CHIP. Liquid biopsy in PrCa should be reserved for patients with relatively higher disease burden or more aggressive growth rate, reflected by PSA values &gt; 4.8 and PSADT &lt; 6 months, to increase the likelihood of identifying actionable alterations and improve interpretation of testing.

CT-guided biopsies of unspecified suspect intrahepatic lesions: pre-procedure Lipiodol-marking improves the biopsy success rate.

While computed tomography (CT)-guided liver biopsies are commonly performed using unenhanced images, contrast-enhanced images are beneficial for challenging puncture pathways and lesion locations. This study aimed to evaluate the accuracy of CT-guided biopsies for intrahepatic lesions using unenhanced, intravenous (IV)-enhanced, or intra-arterial Lipiodol-marked CT for lesion marking. Six-hundred-seven patients (men: 358 [59.0%], mean age 61 years; SD ±12.04) with suspect hepatic lesions and CT-guided liver biopsies were retrospectively evaluated. Successful biopsies were histopathological findings other than typical liver tissue or non-specific findings. Data was ascertained regarding the use of contrast medium for the biopsy-planning CT, unenhanced (group 1) vs. Lipiodol (group 2) vs. IV contrast (group 3). Technical success and influencing factors were insulated. Complications were noted. The results were analyzed using the Wilcoxon-Man-Whitney t-test, Chi-square test, and Spearman-Rho. Overall lesion hitting rate was 73.1%, with significantly better rates using Lipiodol-marked lesions (79.3%) compared to group 1 (73.8%) and group 3 (65.2%) (p = 0.037). Smaller lesions (<20 mm diameter) benefited significantly from Lipiodol-marking with 71.2% successful biopsy rate compared to group 1 (65.5%) and group 3 (47.7%) (p = 0.021). Liver cirrhosis (p = 0.94) and entity of parenchymal lesions (p = 0.78) had no impact on the hitting rate between the groups. No major complications occurred during the interventions. Pre-biopsy Lipiodol marking of suspect hepatic lesions significantly increases the lesion-hitting rate and is especially beneficial for biopsy of smaller targets below 20 mm diameter. Further, Lipiodol marking is superior to IV contrast for non-visible lesions in unenhanced CT. Target lesion entity has no impact on the hitting rate.

Abstract 4334: Clever-1/PD-L1 ratio predicts response to Bexmarilimab, a novel macrophage-guided immunotherapy, in immune deprived cancers

Abstract Introduction: Clever-1 is an immunosuppressive scavenger receptor expressed on tumor associated macrophages. High levels of Clever-1 are associated with poor survival, T-cell exclusion and dysfunction, and immunotherapy resistance. Bexmarilimab (FP-1305) is a novel humanized anti-Clever-1 IgG4-antibody capable of promoting an immune switch, potentially leading to intratumoral proinflammatory responses in patients. In a first-in-human all-comer single agent Phase I/II study in advanced solid tumors (NCT03733990) approximately 30% of patients in hepatocellular carcinoma, cutaneous melanoma and cholangiocarcinoma achieved immune activation, characterized by an IFNg response, which led to a survival benefit (ASCO 2022). Here, we show that patients getting a therapy benefit have immunologically cold tumors with low PD-L1 staining and high Clever-1 staining. Methods: Pre-treatment tumor samples were immunohistochemically stained for Clever-1 (4G9, Santa Cruz) using Ventana platform and scored by % of intratumoral positive cells out of all viable cells and PD-L1 (22C3, Agilent) with combined positivity scoring (CPS). Ratio (PD-L1/Clever-1) at baseline was compared using non-parametric Wilcoxon-test according to clinical benefit. Results: 23 successful baseline biopsies and stainings were obtained, 6 per cutaneous melanoma, 11 per cholangiocarcinoma and 1 per hepatocellular carcinoma, from patients treated with bexmarilimab. Patients had received an average of three previous lines of therapy. At baseline, patients that saw a clinical benefit (CBR) from bexmarilimab had average PD-L1/Clever-1 ratio of 0.2 compared to 4.4 (p=0.042, Wilcoxon nonparametric test) in patients that did not respond to the treatment. Conclusion: PD-L1/Clever-1 IHC staining ratio may be used to predict bexmarilimab responding patients. These patients have a low PD-L1 staining and low IFNg levels as reported previously, and are often refractory to checkpoint inhibitors and other T cell activating agents. Bexmarilimab provides a novel therapy option for a tumor group that is otherwise poorly responsive to immune therapies. Citation Format: Mari L. Björkman, Elisa M. Vuorinen, Juho Jalkanen, Marie-Louise Fjällskog, Jussi Koivunen, Teppo Huttunen, Maija Hollmén, Petri Bono. Clever-1/PD-L1 ratio predicts response to Bexmarilimab, a novel macrophage-guided immunotherapy, in immune deprived cancers. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4334.

Non‑diagnostic electromagnetic navigation bronchoscopy biopsy: Predictive factors and final diagnoses.

The present study aimed to explore the final diagnosis of pulmonary nodules with an initial non-diagnostic result on electromagnetic navigation bronchoscopy (ENB) biopsy and the predictive factors for a non-diagnostic result. A total of 198 nodules from 194 patients that were suspected to be malignant tumors were included in the present study. The initial biopsy pathology results were divided into two groups: The diagnostic group and the non-diagnostic group. The diagnostic group was defined as a successful initial biopsy to obtain a diagnosis, including malignant and benign diagnoses. The non-diagnostic group was defined as a non-specific benign diagnosis, normal lung tissue or an unsuccessful biopsy. Among the 198 nodules, 139 (70.2%) were in the diagnostic group and 59 (29.8%) were in the non-diagnostic group. Predictive factors for a non-diagnostic biopsy included nodule size ≤1.5 cm [odds ratio (OR), 2.05; 95% confidence interval (CI), 1.03-4.09], non-solid nodules (OR, 2.71; 95% CI, 1.33-5.64) and nodules in the left lung (OR, 2.50; 95% CI, 1.27-4.92). Of the 59 non-diagnostic biopsies, 46 were finally confirmed to be malignant by surgery. Notably, non-diagnostic biopsies with non-solid nodules (OR, 7.64; 95% CI, 3.11-18.76) were more likely to be malignant. In conclusion, the predictive factors for a non-diagnostic biopsy were nodule size ≤1.5 cm and non-solid nodules. It was not rare for patients to finally be diagnosed with a malignancy in the non-diagnostic group. Therefore, care should be taken when the results of an ENB are non-diagnostic to prevent misdiagnosis.