Real-Time Tissue Classification Using a Novel Optical Needle Probe for Biopsy.

Core needle biopsy is a part of the histopathological process, which is required for cancerous tissue examination. The most common method to guide the needle inside of the body is ultrasound screening, which in greater part is also the only guidance method. Ultrasound screening requires user experience. Furthermore, patient involuntary movements such as breathing might introduce artifacts and blur the screen. Optically enhanced core needle biopsy probe could potentially aid interventional radiologists during this procedure, providing real-time information on tissue properties close to the needle tip, while it is advancing inside of the body. In this study, we used diffuse optical spectroscopy in a custom-made core needle probe for real-time tissue classification. Our aim was to provide initial characteristics of the smart needle probe in the differentiation of tissues and validate the basic purpose of the probe of informing about breaking into a desired organ. We collected optical spectra from rat blood, fat, heart, kidney, liver, lungs, and muscle tissues. Gathered data were analyzed for feature extraction and evaluation of two machine learning-based classifiers: support vector machine and k-nearest neighbors. Their performances on training data were compared using subject-independent k-fold cross-validation. The best classifier model was chosen and its feasibility for real-time automated tissue recognition and classification was then evaluated. The final model reached nearly 80% of correct real-time classification of rat organs when using the needle probe during real-time classification.

[Post mortem core needle biopsy of Covid-19 fatalities]. / Punción post mortem con aguja gruesa a cadáveres fallecidos por COVID-19.

The difficulties involved in performing autopsies of patients who had died due to COVID-19 required the use of alternative methods in order to obtain tissue samples of affected organs. We describe the technique of core needle aspiration, without ultrasonographic guidance, which we used in 19 cadavers and which produced a high yield in lungs, heart (>94%) and liver (>89%), thus enabling the study of the morphological changes produced by SARS-CoV-2.

Freehand versus Grid-Based Transperineal Prostate Biopsy: A Comparison of Anatomical Region Yield and Complications.

PURPOSE: The freehand (FH) technique of transperineal prostate biopsy using commercialized needle access systems facilitates a reduction in anesthesia requirements from general to local or local/sedation. We sought to compare the efficacy and complication rates of the FH method with those of the standard grid-based (GB) method. MATERIALS AND METHODS: The GB method was performed from 2014 to 2018, and the updated FH technique was performed from 2018 to 2020, yielding comparative cohorts of 174 and 304, respectively. RESULTS: The FH and GB techniques demonstrated equivalent yields of ≥Gleason grade group (GGG)-2 prostate cancer (PCa). The FH group had a significantly higher mean number of cores with ≥GGG-2 PCa involvement (p=0.011) but a significantly lower mean number of biopsy samples (p <0.01). The urinary retention rate of the GB group (10%) was significantly higher than that of the FH group (1%; p <0.01). The rates of ≥GGG-2 PCa involvement in the anterior (GB, 31%) and anteromedial (FH, 22%) sectors were higher than those in other sectors (range, 0%-9%). For multiparametric magnetic resonance imaging, the rate of ≥GGG-2 PCa detection in the anteromedial prostate (23%) was nearly half that in other locations (range, 38%-55%). CONCLUSIONS: Compared with GB transperineal biopsy, FH transperineal biopsy demonstrates an equivalent cancer yield with no risk of sepsis, a significantly reduced risk of urinary retention, and reduced anesthesia needs. The higher number of cores with ≥GGG-2 PCa involvement in the FH group suggests that FH transperineal biopsy can sample the prostate better than GB-transperineal biopsy can.

A new technique for the histological diagnosis of Paget's disease of the breast using a semiautomated core needle biopsy with a 14-gauge needle.

PURPOSE: The aim of our work is to illustrate a new technique for the histological diagnosis of Paget's disease (PD) using a core needle biopsy with a semiautomated 14-gauge needle called nipple-core needle biopsy (N-CNB). We report 3 years' experience in our senology unit. MATERIALS AND METHODS: Twenty-six women with 26 clinical of nipple-areola complex (NAC) changes with suspected PD and subjected to core needle biopsy using our new 14G semiautomated needle technique were included in our study group. Institutional review board approval was obtained for this retrospective analysis. A semiautomated biopsy gun with a 14-gauge, 15-cm-long needle was used for this new procedure. After a subcutaneous injection of anesthetic and spray-ice application to the NAC, the 14G needle was opened with the cradle exposed and positioned on the NAC with considerable pressure exerted on the same. The cradle was then closed by triggering the needle spring, and 2-4 core samples were withdrawn by moving the needle position each time. Clinical, instrumental and histological differences between the lesions that gave benign results after N-CNB and those that resulted PD were analyzed by applying the Fisher's exact test. RESULTS: After N-CNB, 13/26 lesions were found to be PD (50%) while 13/26 alterations were benign (50%). No malignant lesions were detected during the follow-up in patients with benign N-CNB results. The diagnosis of PD obtained with N-CNB was confirmed in all 13 cases by means of a histological analysis of the surgical specimens. No significant post-biopsy complications were recorded. Patients with PD more frequently presented nipple retraction (ρ = 0.0407) and associated suspicious (i.e., BI-RADS 4 and 5) mammographic (ρ = 0.0006) findings compared to patients whose N-CNB had given benign results and the difference was statistically significant. CONCLUSIONS: In conclusion, with this novel technique, we were able to obtain an easy, painless, major complication-free and accurate diagnosis of PD of the NAC using a semiautomated core needle biopsy with a 14-gauge needle.

Transjugular Liver Biopsy in Patients with Liver Transplantation: Comparison of Quick-Core Biopsy and Forceps Biopsy.

PURPOSE: To compare the safety and efficacy of transjugular liver biopsy (TJLB) using a Quick-Core biopsy needle or a forceps biopsy in patients with liver transplantation (LT) who were suspected of having rejection. MATERIALS AND METHODS: From June 2015 to January 2017, 98 TJLBs (60 patients) with the Quick-Core biopsy needle and 95 TJLBs (58 patients) with a forceps biopsy system were attempted in patients with LT suspected of having rejection. Technical success, adequacy for diagnosis, number of biopsy instrument passes, the maximum and mean length of the obtained samples, and the complications were retrospectively analyzed. RESULTS: TJLB was technically successful in all patients. Adequate specimens were obtained in 95.9% of the biopsy needle group and 91.6% in the forceps group (p = 0.246). The mean number of biopsies was 4.8 ± 1.8 in the biopsy needle group and 6.2 ± 1.7 in the forceps group. The mean size of the biopsy sample was 11.1 ± 3.0 mm in the biopsy needle group and 2.5 ± 1.2 mm in the forceps group. Only one minor complication (a subcapsular hematoma) occurred in the biopsy needle group. No major complication was observed in any patient. CONCLUSION: TJLB using a Quick-Core biopsy needle or forceps can be safely and effectively performed in LT patients. The adequacy of sampling for diagnosis was equivalent between the groups. LEVEL OF EVIDENCE: Level 4, case series.

The Ability to Look: Management of Breast Disease in the Democratic Republic of the Congo Using Smart Ultrasound Technology.

BACKGROUND: The vast majority of women with breast cancer in sub-Saharan Africa present with advanced stage disease, due primarily to the lack of opportunities for early detection and treatment. As part of a larger effort to increase access to diagnostic and therapeutic services for women's cancers in the Democratic Republic of Congo (DRC), we implemented a curriculum to train the local workforce and a program to build the supportive infrastructure for the diagnosis and treatment of breast cancer at a private sector health facility (Biamba Marie Mutombo Hospital) in Kinshasa. STUDY DESIGN: After onsite trainings in the DRC by a US breast surgeon (RT), Congolese surgeons, general physicians, physician assistants, and nurses used the Phillips Lumify smart-phone ultrasound device to perform and interpret the results of whole breast ultrasound on symptomatic women. Surgeons were trained to perform ultrasound-guided core needle biopsy on those who met the criteria for tissue diagnosis, after which they trained nurses to do the same. RESULTS: Over 3 years, 5,211 patients were identified as having a breast abnormality on clinical breast examination. Ultrasound abnormalities were noted in 1,493 (27%) patients, of which 632 (42%) met the criteria for ultrasound-guided core needle biopsy or fine needle aspiration. Pathology reports were available on 368 (58%) patients who underwent biopsy, of which 164 were malignant and 204 benign. CONCLUSIONS: We demonstrated how the "ability to look" using smart technology can be successfully used to augment clinical breast exam and triage patients for biopsy in a resource-constrained African setting.

A well-tolerated core needle muscle biopsy process suitable for children and adults.

Serial muscle biopsies within clinical trials for Duchenne muscular dystrophy (DMD) are critical to document therapeutic responses. Less invasive means of sampling muscle are needed. We analyzed a retrospective consecutive case-series cohort of vacuum-assisted core needle muscle biopsy procedures performed on healthy and dystrophic individuals at a single institution assessing for safety and reliability of obtaining sufficient high-quality biopsy tissue for histologic assessment in adult and pediatric subjects. Of 471 muscle cores from 128 biopsy procedures, 377-550 mg of total muscle tissue was obtained per procedure with mean core weight of 129 mg (SD, 25.1 mg). All biopsies were adequate for histological assessment. There were no significant adverse events. This core needle biopsy approach, when combined with improved sample processing, provides a safe means to consistently obtain muscle samples for diagnostic and clinical trial applications.

MRI-guided core needle biopsy of the breast: Radiology-pathology correlation and impact on clinical management.

OBJECTIVE: Breast MRI is used to screen high-risk patients and determine extent of disease in breast cancer (BC) patients. The goal of this study was to determine the pathologic correlates of breast MRI abnormalities biopsied under MRI guidance. METHODS: We retrospectively identified 101 MRI-guided core needle biopsies (CNB) of the breast from 79 women over a 4-year period. MRI-detected lesions biopsied with ultrasound or stereotactic guidance were excluded. MRI studies and pathology were reviewed by breast radiologists and pathologists. RESULTS: Of the 79 patients, 72 (91%) had a history of prior (n = 13) or concurrent (n = 59) BC. There were 101 MRI abnormalities: 60 (59%) with non-mass enhancement (NME) and 41 (41%) with mass enhancement. Pathology was benign in 83/101 (82%), including in the majority of NME lesions (43/60, 72%). The most common benign findings were: fibrocystic changes (FCC) (49%), sclerosing lesions (13%), and fibroadenoma (FA) (9%). There were 18 (18%) malignant diagnoses: 8 (44%) invasive lobular carcinoma (ILC), 7 (39%) ductal carcinoma in situ (DCIS), and 3 (17%) invasive ductal carcinoma (IDC). Of the 18 malignant diagnoses, 16 (89%) occurred in 14 unique patients with concurrent BC. Based on the malignant MRI-guided CNB, 6 (46%) of these patients had additional (sentinel lymph node biopsy or contralateral breast surgery) or more extensive (wider lumpectomy) surgery. CONCLUSION: In this series, most MRI-guided CNB of the breast were benign. The vast majority of malignant diagnoses occurred in patients with concurrent BC and frequently resulted in changes in clinical management.

Reduction of Radiation Dose and Scanning Time While Preserving Diagnostic Yield: A Comparison of Battery-Powered and Manual Bone Biopsy Systems.

BACKGROUND AND PURPOSE: There is scarcity of data on the comparative efficacy between bone biopsy drill systems across various types of bone lesions. Our aim was to investigate differences in diagnostic yield, scanning time, and radiation dose between manual and battery-powered bone biopsy systems in CT-guided biopsies of lytic, sclerotic, and infectious bone lesions. MATERIALS AND METHODS: This was a retrospective single-center institutional review board-approved study. A total of 585 CT-guided core needle biopsies were performed at 1 institution from May 2010 to February 2019. Classification of bone lesions, location, bone biopsy system, suspected origin of primary disease, final pathologic diagnosis, diagnostic yield, presence of crush artifacts, radiation dose, and scanning times were collected. For the battery-powered system, OnControl was used. For the manual drill system, Bonopty, Osteo-site, and Laurane drill systems were used. Comparisons in lytic and sclerotic lesions and suspected discitis/osteomyelitis were made using the Fisher exact test. Subgroup analysis of the drill systems for scanning time and radiation dose was performed by 1-way ANOVA. RESULTS: Our patient cohorts consisted of a total of 585 patients with 422 lytic, 110 sclerotic, and 53 suspected infectious lesions. The mean age was 62 ± 13 years with a male/female ratio of 305:280 for all lesions. The diagnostic yield was 85.5% (362/422) for lytic, 82.7% (91/110) for sclerotic, 50.9% (27/53) for infectious lesions, and 82.1% (480/585) for all lesions. No statistical difference was found when comparing diagnostic yields of powered drills with the manual systems for lytic, sclerotic, and infectious lesions. However, in a subgroup analysis, radiation dose and scanning time were significantly lower for powered drill compared with manual drill systems in lytic (P = .001 for both) and sclerotic lesions (P = .028 and P = .012, respectively). No significant differences were seen between the drill systems for suspected infectious lesions. CONCLUSIONS: Our findings demonstrate that there was no statistically significant difference in diagnostic yield when comparing battery-powered and manual bone biopsy systems for CT-guided bone biopsies; however, the use of the power drill system resulted in significantly reduced scanning time and radiation dose in lytic and sclerotic lesions.

Ultrasound-Guided Breast Biopsy: Improved Accuracy of 10-G Cable-Free Elite Compared With 14-G CCNB.

BACKGROUND: Imaging-guided breast biopsy is crucial for breast lesion evaluation. We aim to make the first comprehensive comparison of two different ultrasound-guided breast biopsy devices: 14-G conventional core needle biopsy (CCNB) and the newly applied cable-free, low-vacuum-assisted 10-G breast biopsy system, Elite. METHODS: We retrospectively collected patients with suspected breast cancer who underwent ultrasound-guided 14-G CCNB or 10-G Elite from October 2013 through March 2018 and compared the biopsy result with the result after operation. We analyzed the test performance of the two methods and their accuracy in immunohistochemistry assays mainly including estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and Ki67. We also analyzed the accuracy of 10-G Elite with frozen sections. RESULTS: Six hundred seventy-four patients who underwent 14-G CCNB and 592 patients who underwent 10-G Elite were finally included in the research. Negative predictive value with Elite was higher than with CCNB (Elite 86.5%, CCNB 41.7%, P < 0.001). Sensitivity (Elite 97.7%, CCNB 96.2%, P = 0.1), specificity (Elite 98.7%, CCNB 90.0%, P = 0.1), positive predictive value (Elite 99.8%, CCNB 99.7%, P = 0.7), and false negative rate (Elite 2.3%, CCNB 3.8%, P = 0.1) showed no difference between two devices. In terms of immunohistochemistry assay, Ki67 agreement of Elite was higher than that of CCNB (Elite 79.5%, CCNB 73.4%, P = 0.045). Estrogen receptor agreement (Elite 90.6%, CCNB 87.7%, P = 0.2), progesterone receptor agreement (Elite 83.9%, CCNB 80.9%, P = 0.3), and human epidermal growth factor receptor two agreement (Elite 94.2%, CCNB 93.5%, P = 0.7) showed no difference between Elite and CCNB. The rate of an inconclusive biopsy result was lower with Elite than with CCNB (Elite 1.5%, CCNB 3.3%, P = 0.045). CONCLUSIONS: 10-G Elite has higher negative predictive value, higher Ki67 agreement, and lower inconclusive results than 14-G CCNB. Elite can be a reliable substitute for 14-G CCNB.

Limitaciones diagnósticas de las determinaciones inmunohistoquímicas preoperatorias en el linfoma anaplásico de células grandes asociado a implante mamario (LACG-AIM) / Diagnostic limitations of preoperative immunohistochemical determinations in breast implant associated anaplastic large cell lymphoma (BIA-ALCL)

Presentamos un caso de linfoma anaplásico de células grandes asociado a implante mamario (LACG-AIM) que debutó como seroma periprotésico unilateral izquierdo de características acelulares en su estudio inicial. Esto limitó la determinación inmunohistoquímica de marcadores CD30 y cinasa del linfoma anaplásico (ALK) y su diagnóstico preoperatorio. La paciente fue intervenida quirúrgicamente realizándose retirada del implante y capsulectomía completa bilateral. El estudio anatomopatológico de la cápsula periprotésica izquierda mostró un linfoma anaplásico de células grandes. Dado que algunos casos de LACG-AIM pueden presentarse sin celularidad en el seroma periprotésico, limitando la efectividad de las determinaciones inmunohistoquímicas preoperatorias, en casos de alta sospecha clínica cabría plantearse un tratamiento quirúrgico de forma precoz que iniciase el tratamiento oncológico sin demora y aportase un diagnóstico definitivo

We present a case of breast implant associated anaplastic large cell lymphoma (BIA-ALCL) that debuted as a left unilateral periprosthetic seroma of acellular features in its initial study. This aspect limited the immunohistochemical determination of CD30 markers and anaplastic lymphoma kinase (ALK) and its preoperative diagnosis. Patient was operated performing implant removal and bilateral complete capsulectomy. The pathological study of the left periprosthetic capsule showed an anaplastic large cell lymphoma. Since some cases of BIA-ALCL can occur without cellularity in the periprosthetic seroma, limiting the effectiveness of preoperative immunohistochemical determinations, in cases of high clinical suspicion an early surgical treatment could be considered in order to begin the oncological treatment without delay and providing a definitive diagnosis

Embolia gaseosa arterial: una rara complicación de la biopsia con aguja gruesa en el diagnóstico del nódulo pulmonar solitario / Arterial Gas Embolism: A Rare Complication of Core Needle Biopsy in the Diagnosis of Solitary Pulmonary Nodule

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EUS-guided core liver biopsy sampling using a 22-gauge fork-tip needle: a prospective blinded trial for histologic and lipidomic evaluation in nonalcoholic fatty liver disease.

BACKGROUND AND AIMS: Diagnostic tools for nonalcoholic fatty liver disease (NAFLD) detection and prognostication are limited, with histology remaining the criterion standard. We evaluated the feasibility and safety of EUS-guided liver biopsy (EUS-LB) sampling in NAFLD staging. METHODS: In a prospective cohort of NAFLD patients with steatohepatitis and early liver fibrosis based on magnetic resonance elastography (MRE), EUS-LB sampling procedures were performed using a 22-gauge fork-tip core biopsy needle. Samples were evaluated by a blinded pathologist. Total aggregate sample length (TASL), number of complete portal triads, ability to calculate NAFLD activity score, ability to stage liver fibrosis, and ability to provide enough core liver tissue for lipidomics analysis were evaluated. Performance of EUS-LB sampling was compared with MRE. RESULTS: Forty-one EUS-LB samples were obtained. The median TASL was 2.4 cm (interquartile range, 2.00-2.75). The median number of complete portal triads per TASL was 26 (interquartile range, 7-62). Of the samples, 100% were adequate to convey NAFLD activity score and fibrosis stage. All samples provided enough core liver tissue to allow the application of lipidomics testing. A significant positive linear association between EUS-LB sampling-detected fibrosis and MRE-detected fibrosis was observed (r = .469, P < .005). Compared with MRE, EUS-LB sampling established early fibrosis in 13 cases that MRE classified as normal. EUS-LB sampling-related adverse events occurred in 7% and were restricted to postprocedural pain. CONCLUSIONS: EUS-LB sampling is a viable technique for full NAFLD evaluation and may be superior to MRE in establishing the diagnosis of nonalcoholic steatohepatitis with early fibrosis. (Clinical trial registration number: NCT02880189.).

19 G aspiration needle versus 19 G core biopsy needle for endoscopic ultrasound-guided liver biopsy: a prospective randomized trial.

BACKGROUND: Endoscopic ultrasound-guided liver biopsy (EUS-LB) is a safe and effective method for accomplishing parenchymal liver biopsy. The aim of this study was to compare a 19 G aspiration needle (FNA) with a 19 G Franseen-tip core biopsy needle (FNB) for EUS-LB. METHODS: This was a prospective, parallel group, randomized trial comparing the tissue yields and adequacy of a 19 G FNA needle vs. a 19 G FNB needle for EUS-LB. The primary outcome was length of the longest piece of liver core specimen. Secondary outcomes were aggregate specimen length, number of complete portal triads (CPTs), and adverse events. One transgastric pass and one transduodenal pass were performed with the same needle in each patient. Specimen lengths were measured before and after histological processing. RESULTS: 40 patients referred for EUS-LB were randomized to either the FNA group (n = 20) or the FNB group (n = 20). Both groups had similar patient characteristics. FNB biopsies yielded longer mean (standard deviation) specimen lengths (pre-processing mean 2.09 cm [0.41] vs. mean 1.47 cm [0.46], and post-processing mean 1.78 cm [0.66] vs. mean 1.05 cm [0.42]; both P < 0.001), a longer aggregate specimen length (pre-processing mean 15.78 cm [5.19] vs. 10.89 cm [4.38]; P = 0.003), and more CPTs (mean 42.6 25 vs 18.1 [9.3]; P < 0.001) compared with the FNA needle. There were no severe adverse events or difference in adverse event rate between the two needles. Post-biopsy pain was noted in 37.5 %. CONCLUSION: EUS-LB using the FNB needle delivered longer liver biopsy specimens with more CPTs than the regular (non-core) needle.

EUS-guided core biopsies of pancreatic solid masses using a new fork-tip needle: A multicenter prospective study.

BACKGROUND AND AIM: Endoscopic ultrasound-guided sampling (EUS sampling) is a safe and effective technique. The study aim was to evaluate the presence of a histological core from pancreatic lesions using a new 25G fork-tip needle. METHODS: Observational multicenter prospective and analytical study, including consecutive patients with solid pancreatic masses referred for EUS-guided sampling. At each needle pass, the endoscopist performed macroscopic on-site evaluation (MOSE). The primary outcome was the histological core procurement rates. Secondary outcomes were the evaluation of interobserver agreement between endoscopists and pathologists, adequacy of EUS samples for the diagnosis and post-procedure adverse events. RESULTS: 100 patients were enrolled in 3 centers. The mean size of the lesions was 28.5 mm (SD 11.7). Final diagnoses were adenocarcinoma (68%), neuroendocrine tumor (21%), inflammatory mass/benign lesions (8.0%), and pancreatic metastasis (3.0%). The pathologists described the presence of a core in 67 samples (67.0% of patients), with poor agreement with MOSE (kappa, 0. 12; 95% CI: 0.03-0.28). The diagnostic accuracy was 93%. We observed 6% of mild adverse events. CONCLUSION: The new 25-gauge core needle showed good overall adequacy and a good rate of histological specimens during EUS sampling of solid pancreatic masses, with a minimum number of passes and no major complications. Clinicaltrial.gov number, NCT02946840.

Ex vivo performance comparison of three percutaneous biopsy needle systems.

PURPOSE: The aim of this study is to identify the micro-mechanical characteristics that define biopsy performance in normal ex vivo animal organs. MATERIALS AND METHODS: Three biopsy systems with differences of needle external diameter, tray height and effective tray length were assessed. Sampling was performed in porcine liver and kidneys with commercially labelled 14G, 16G and 18G, using 2-cm throw needle systems. Five samples were obtained per needle size and per organ, and the experiment was repeated twice for a total of 90 biopsy cores. Samples were analysed and compared in terms of macroscopic aspect, sample length, weight and tissue architecture. RESULTS: The system with the longest effective needle tray (system A) has shown significant superiority (p < 0.001) versus the other systems regarding the mean weight of tissue obtained for all needle sizes. Furthermore, the 14G needle of system A has shown superiority regarding the number of portal spaces and the 16G regarding the length of kidney fragments obtained. CONCLUSION: The outcomes obtained with the different biopsy systems were not equal. The micro-mechanical characteristic that appears to influence the quantity and quality of the obtained tissue is the effective needle tray length and not the needle external diameter or the needle tray height. This information should be taken into account in the future design of biopsy needle systems, particularly when potentially used in the assessment of biomarkers and the characterisation of tumour micro-environment. KEY POINTS: • The amount of obtained tissue mass is not the same among percutaneous biopsy needle systems. • There are different micro-mechanical characteristics that condition the amount of obtained tissue. • The micro-mechanical characteristic that offers more tissue mass for the same calibre is the effective length of the needle tray.

Comparison of the Diagnostic Yield of the Standard 22-Gauge Needle and the New 20-Gauge Forward-Bevel Core Biopsy Needle for Endoscopic Ultrasound-Guided Tissue Acquisition from Pancreatic Lesions.

Background/Aims: To compare the diagnostic yield of 20-gauge forward-bevel core biopsy needle (CBN) and 22-gauge needle for endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) of solid pancreatic masses. Methods: The use of 20-gauge CBN was prospectively evaluated for 50 patients who underwent EUS-FNA from June 2016 to December 2016. Data were compared with those obtained by a retrospective study of 50 consecutive patients who underwent EUS-FNA using standard 22-gauge needles between December 2016 and April 2017. At least two punctures were performed for each patient; the sample from the first pass was used for cytology with or without histology and that from the second pass was used for histology. Sample quantity was evaluated using the sample obtained from the second pass. Results: There was no significant difference in the diagnostic accuracy rate between the first and second passes (20-gauge CBN: 96% [48/50]; standard 22-gauge needle: 88% [44/50]). Samples >10× power fields in length were obtained from 90% (43/48) and 60% (30/50) of patients using the 20-gauge CBN and standard 22-gauge needle, respectively (p=0.01). Technical failure occurred for two patients with the 20-gauge CBN. Conclusions: Diagnostic accuracy of the 20-gauge CBN was comparable to that of the 22-gauge needle. However, two passes with the 20-gauge CBN yielded a correct diagnosis for 100% of patients when technically feasible. Moreover, the 20-gauge CBN yielded core tissue for 90% patients, which was a performance superior to that of the 22-gauge needle.