***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND AND STUDY AIMS Histological examination of core tissue sample s may have advantages over cytology in endoscopic ultrasound (EUS)-guided sampling . We aim ed to evaluate the feasibility and efficiency of a new 22 G core biopsy needle . PATIENTS AND METHODS Consecutive patients with a pancreatic mass lesion or peri-intestinal lymphadenopathy sequentially underwent fine needle biopsy with both a newly developed 22 G core needle ( the FNB needle ) and a st and ard 22 G fine needle aspiration ( FNA ) needle , in r and omized order . RESULTS In 144 patients , mean age 48 years ( ± st and ard deviation [ SD ] 14 ; range 18 - 82 ) , with 145 lesions ( mean lesion size 39 ± 15 mm , range 15 - 99 ) , EUS-guided sampling was technically feasible with both needles in all patients . Mean number of passes to obtain sufficient tissue was 1.2 ± 0.5 with the core needle vs. 2.5 ± 0.9 with the st and ard needle ( P < 0.001 ) . FNB specimens were adequate for evaluation in 125 ( 86.2 % ) vs. 127 ( 87.6 % ) with FNA ( P = 0.72 ) . Among 139 patients available for follow-up , FNB provided a correct diagnosis in 110 ( 79.1 % ) and FNA in 112 ( 80.6 % ) ( P = 0.73 ) . Sensitivity , specificity , positive and negative predictive values , and accuracy for diagnosis of malignancy were 90 % , 100 % , 100 % , 93 % , 96 % for FNB and 77 % , 100 % , 100 % , 85 % , 92 % for FNA , respectively ( P > 0.05 ) . CONCLUSION FNB with the new 22 G core needle was technically feasible , efficient and comparable to FNA with a st and ard needle . The core needle required fewer passes to provide an adequate sample , offering potentially shorter procedure time BACKGROUND A trucut needle biopsy device that can be used to obtain specimens from the pancreas and other perigastric organs under EUS guidance has been developed and successfully tested in animals . Moreover , EUS-guided trucut needle biopsy has been used safely in humans and appears to provide more accurate results than EUS-guided FNA . This study prospect ively assessed the clinical utility of this new device in patients with solid pancreatic masses . METHODS Twenty-three consecutive patients with radiologically detected solid pancreatic masses underwent EUS-guided trucut needle biopsy . Pancreatic malignancy detected by EUS-guided trucut needle biopsy was considered a definitive diagnosis . Further diagnostic procedures and clinical course were used to establish or exclude the presence of malignancy in all other patients . RESULTS Pancreatic tissue was obtained in 17 of the 23 patients ( 74 % ) , including all patients in whom the transgastric approach was used . No acute or long-term complication was observed . Histopathologic evaluation revealed pancreatic cancer in 12 patients . CT-guided biopsy specimens were obtained in 4 of the 5 patients with a negative EUS-guided trucut needle biopsy result ; two were positive for adenocarcinoma . Overall diagnostic accuracy was 61 % . Subgroup analysis of the 16 patients in whom EUS-guided trucut needle biopsy was successful and who were available for follow-up revealed a diagnostic accuracy of 87.5 % . CONCLUSIONS This prospect i ve study demonstrates that EUS-guided trucut needle biopsy , when performed transgastrically , is safe and accurate in the evaluation of patients with solid pancreatic masses The specific needle sizes/types used in performing endoscopic ultrasound-guided fine needle aspirations ( EUS-FNA ) vary . The HD ProCore ( ™ ) is a 22-gauge beveled needle allowing for core biopsy along with aspiration material . In this study we compare this needle with a st and ard 22-gauge needle .  Between April 1 , 2011 and November 15 , 2011 , 18 patients undergoing EUS-FNA using the HD ProCore ( ™ ) needle were compared to a control group of 18 cases using the st and ard 22-gauge needle .  Smears were assessed for : three-dimensional clusters , thick obscuring clusters , monolayer sheets , cellularity , crowded obscuring single cells , blood , and nuclear staining . Cell blocks were assessed for cellularity and presence of diagnostic material . Records were review ed for the overall adequacy , number of FNA passes , and patient follow-up . Overall , the two needle groups demonstrated similar results for the cytology parameters , amount of diagnostic cell block material , adequacy , and accuracy . The mean number of passes to achieve adequacy varied between the groups [ 2.94 for the st and ard 22-gauge needle group versus 2.11 for the beveled needle group ( P=0.03 ) ] with no meaningful difference in case duration between needle groups . No complications were reported . The beveled EUS needle affords similar cytologic interpretability , adequacy , diagnostic accuracy , and amount of cell block material as a st and ard needle . There was a statistically significant trend toward fewer passes to achieve adequacy with the beveled EUS-FNA needle . Therefore , the EUS-FNA needle with a lateral bevel is a diagnostically similar alternative to st and ard endoscopy needles , the possibility that this beveled needle may improve per pass adequacy requires further verification Background and aims : Endoscopic ultrasound‐guided fine needle aspiration ( EUS‐FNA ) has a diagnostic accuracy of 70–90 % , depending on the site under evaluation . In order to improve EUS‐guided tissue sampling a novel 19‐gauge trucut‐type needle has been design ed to obtain core biopsies during EUS . We prospect ively evaluated the safety and accuracy  of EUS‐FNA alone versus combined EUS‐FNA and trucut needle biopsy ( TNB ) in patients referred to our Unit over a 3‐year period Abstract Objective . Endoscopic ultrasonography (EUS)-guided fine-needle aspiration ( EUS-FNA ) may facilitate tissue sampling for histopathological diagnosis of subepithelial tumors ( SETs ) in the gastrointestinal ( GI ) tract . However , immunohistochemistry is not always feasible using EUS-FNA sample s due to the low quality of specimens often obtained by aspiration . This study aim ed to compare the use of 22-gauge ( G ) EUS-guided fine-needle biopsy ( EUS-FNB ) with 22 G EUS-FNA for core sampling used for histopathological examination , including immunohistochemistry , in patients with GI SETs . Methods . Twenty-eight patients with GI SETs ≥2 cm in size were prospect ively enrolled at five university hospitals in Korea between January and June 2013 . They were r and omized to undergo either  EUS-FNB  or  EUS-FNA . Results . A total of 22 patients was finally analyzed in this study : 10 and 12 patients underwent EUS-FNA and EUS-FNB  , respectively . Compared to the EUS-FNA group , the EUS-FNB group had a significantly lower median number of needle passes to obtain macroscopically optimal core sample s ( 4 vs. 2 , p = 0.025 ) ; higher yield rates of macroscopically and histologically optimal core sample s with three needle passes ( 30 % vs. 92 % , p = 0.006 ; 20 % vs. 75 % , p = 0.010 , respectively ) ; and a higher diagnostic sufficiency rate ( 20 % vs. 75 % , p = 0.010 ) . No technical difficulties were encountered in either group . Conclusions . This study shows that EUS-FNB has a better ability to obtain histological core sample s and a higher diagnostic sufficiency rate than EUS-FNA and that EUS-FNB is a feasible , safe , and preferable modality for adequate core sampling for histopathological diagnosis of GI SETs BACKGROUND AND STUDY AIMS The fanning technique for endoscopic ultrasound-guided fine-needle aspiration ( EUS - FNA ) involves sampling multiple areas within a lesion with each pass . The aim of this study was to compare the fanning and st and ard techniques for EUS - FNA of solid pancreatic masses . PATIENTS AND METHODS Consecutive patients with solid pancreatic mass lesions were r and omized to undergo EUS - FNA  using either the st and ard or the fanning technique . The main outcome measure was the median number of passes required to establish diagnosis . The secondary outcome measures were the diagnostic accuracy , technical failure , and complication rate of the two techniques . RESULTS Of 54 patients , 26 were r and omized to the st and ard technique and 28 to the fanning technique .  There was no difference in diagnostic accuracy ( 76.9 % vs. 96.4 % ; P = 0.05 ) , technical failure or complication rates ( none in either cohort ) . There was a significant difference in both the number of passes required to establish diagnosis ( median 1 [ interquartile range 1 - 3 ] vs. 1 [ 1 - 1 ] ; P = 0.02 ) and the percentage of patients in whom a diagnosis was achieved on pass one ( 57.7 % vs. 85.7 % ; P = 0.02 ) between the st and ard and fanning groups , respectively . CONCLUSIONS The fanning technique of FNA was superior to the st and ard approach because fewer passes were required to establish the diagnosis . If these promising data are confirmed by other investigators , consideration should be given to incorporating the fanning technique into routine practice of EUS - FNA . Registered at Clinical Trials.gov ( NCT 01501903 ) BACKGROUND AND STUDY AIMS The aim of this prospect i ve study was to compare fine-needle aspiration guided by endoscopic ultrasonography ( EUS-FNA ) using 25-gauge and 22-gauge needles with the EUS-guided 19-gauge Trucut needle biopsy ( EUS-TNB ) in patients with solid pancreatic mass . PATIENTS AND METHODS Twenty-four consecutive patients with pancreatic mass underwent biopsies by both EUS-FNA and EUS-TNB .  Three needles were compared with respect to technical success rate , tissue size obtained , overall diagnostic accuracy and accuracy for histological and cytological diagnosis . RESULTS The 25-gauge EUS-FNA was technically easier and obtained superior overall diagnostic accuracy than the 22-gauge and Trucut needles , especially in lesions of the pancreas head and uncinate process . Overall accuracy for the 25-gauge , 22-gauge and Trucut needle was 91.7 % , 79.7 % and 54.1 % , respectively . Accuracy for cytological diagnosis irrespective the site of lesions with 25-gauge , 22-gauge and Trucut needles was 91.7 % , 75.0 % , and 45.8 % , respectively . For uncinate masses , it was 100 % , 33.3 % , and 0.0 % , respectively . These differences were significant . Among technically successful patients , the accuracy for histological diagnosis using the 25-gauge was significantly inferior ( P < 0.05 ) to 22-gauge and Trucut needles and the rates were 45.8 % , 78.9 % and 83.3 % . CONCLUSIONS The 25-gauge FNA needle was significantly superior in terms of technical success rate and overall diagnostic accuracy , especially for the head and uncinate lesions , compared to the 22-gauge and Trucut needles and could be considered ' the best choice needle for cytological diagnosis ' of solid pancreatic lesions . If histological diagnosis is required , the 22-gauge FNA needle and Trucut needle may be advantageous for use in head/uncinate and body/tail lesions , respectively Endoscopic ultrasound-guided fine-needle aspiration ( EUS-FNA ) is widely used for diagnosis of pancreatic lesions . The Echotip Procore Needle ( Wilson-Cook Medical ) is a new 22 G fine biopsy needle ( FNB ) for obtaining core biopsy material at time of EUS . This study aim ed to compare the technical and diagnostic performance of conventional FNA and FNB .  Thirty-two patients met the design criteria for this prospect i ve paired cohort study . All lesions sample d were solid ( non-cystic ) pancreatic masses by EUS appearance . Patients were r and omized to receive FNA or FNB by first attempt . A cytopathologist performed on-site evaluations . Sample s were assessed for accuracy of diagnosis , cellularity , contamination , and sufficiency for ancillary studies . Technical and diagnostic performances were compared . Compared to FNA , there was a statistically significant decreased ability of FNB to achieve a diagnosis ( FNA 93.8 % , FNB 28.1 % , P < 0.001 ) . FNB was diagnostically superior to FNA in 1 of 32 cases . Technical failures were observed in five cases due to resistance to advancement of the FNB needle . Regarding operator perceived ease-of-use , FNA outperformed F 
    Output:
    
Current data do not demonstrate a significant difference between the ProCore and st and ard FNA needles for sample adequacy , diagnostic accuracy or acquisition of a core specimen .
However , the ProCore needle establishes the diagnosis with fewer passes