Prospective Study Comparing Methods of Obtainment of Specimen After EUS-FNA in Patients With Peri-pancreatic Mass
Condition: Pancreatic Neoplasm; Neoplasm of Intra-abdominal Lymph Nodes
MeSH terms: Neoplasms; Pancreatic Neoplasms
Study type: Interventional

Summary: 
      EUS-guided FNA has been proved to be a safe and useful method for tissue sampling of
      gastrointestinal track lesions and other organ lesions including mediastinal and
      intra-abdominal lymph nodes, pancreas and hepatobiliary tree. The usefulness of EUS-FNA
      depends on several factors. For example, experience of the endosonographers, adequate
      sampling, sample preparing, accurate interpretation by the cytopathologist and on-site
      cytopathology interpretation. However, in many hospitals, no cytopathologist can be present
      during EUS-FNA. Therefore, determining appropriate methods to obtain and prepare EUS-guided
      FNA are important to make correct a diagnosis without on-site cytopathologist.

      Suction with a self-retracting 10-mL syringe will likely bring in more cellularity but also
      more blood. Some endosonographers use no suction, others use constant suction. Usually
      specimen is expelled from a needle with pushing the stylet into the needle. But use of the
      stylet during EUS-FNA is difficult and time consuming process. Injecting air was not
      recommended, because of spraying out uncontrollably, increasing risk of air artifact and
      specimen clotting. However, there is no further study which one is the appropriate, suction
      or no suction and pushing the stylet or injecting air until now.

      The hypothesis and aim of the prospective randomized controlled trials are as follows:

      First hypothesis: There was no difference in the adequacy, cellularity, bloodiness,
      contamination, air artifact in specimen obtained by each methods, suction or no suction and
      pushing the stylet or injecting air.

      Aim #1 : To compare the adequacy, cellularity, bloodiness, contamination, air artifact in
      specimen obtained by each methods, suction or no suction and pushing the stylet or injecting
      air.

      Second hypothesis: There was no difference in sensitivity, specificity, diagnostic accuracy,
      positive predictive value, negative predictive value and statistical agreement in specimen
      obtained by each methods, suction or no suction and pushing the stylet or injecting air.

      Aim #2 : To compare the sensitivity, specificity, diagnostic accuracy, positive predictive
      value, negative predictive value and statistical agreement in specimen obtained by each
      methods, suction or no suction and pushing the stylet or injecting air.
    

Detailed description: 
      On-site cytopathology interpretation during EUS-FNA has a significant clinical impact by
      increasing the diagnostic yield of the FNA. However, many hospitals do not have provision for
      on- site diagnosis of EUS FNA specimen. Therefore, optimal specimen obtainment and
      preparation of EUS FNA are is important to accurate diagnosis. EUS FNA is performed with or
      without self-retracting 10-mL syringe according to endosonographer's preference. In general,
      if there is too little cellularity on immediate cytologic evaluation, then use more suction,
      and, conversely, if the samples are too bloody, then use less suction. However, it is hard to
      determine the quality of specimen without on-site cytopathology interpretation. The actual
      way material is expressed from the needle may influence yield. Injecting air to express the
      material is problematic, because the material may spray out uncontrollably, risk of air
      artifact and specimen clotting may increase . A more controlled method is to pushing the
      stylet and slowly advance it to the needle tip. But use of the stylet during EUS-FNA is not
      only difficult and time consuming process but also increasing the risk of accidental needle
      stick injury. However, there is no firm evidence which one is the appropriate, suction or no
      suction and pushing the stylet or injecting air. If there was no significant difference
      between each methods, appropriate methods of obtaining and preparing aspirates undergoing
      EUS-FNA is no suction and injecting air and EUS FNA may perform more easier and shorter.

      In this prospective randomized controlled trial, patients with peripancreatic mass for
      EUS-FNA will be included. One patient will be underwent at least four puncture during
      EUS-FNA. The sequence of EUS-FNA with first four methods will be selected by using a
      randomization scheme obtained from a sealed envelope : (1) negative pressure suction with 10
      mL syringe and pushing the stylet; (2) negative pressure suction with 10 mL syringe and
      injecting air; (3) without negative pressure suction and pushing the stylet; (4) without
      negative pressure suction and injecting air. EUS FNA will be performed by two experienced
      endosonographers. All specimens will be read by same experienced pathologist blinded to
      methods.

      The investigators will compare between the four groups in terms of adequacy, cellularity,
      bloodiness, contamination, air artifact. The sensitivity, specificity, diagnostic accuracy,
      positive predictive value, negative predictive value and statistical agreement for the
      different methods will be calculated.
    

Intervention name(s): 1.EUS-FNA with or without suction; 2.Pushing the stylet or injecting air
Intervention type(s): Procedure; Procedure
Intervention description(s): During EUS-FNA of the peri-pancreatic mass was performed, with or without self-retracting 10-mL syringe applied.; EUS-FNA specimen is expelled from a needle with pushing the stylet or injecting air into the needle
Other intervention name(s): EUS-FNA with or without suction; Pushing the stylet or injecting air
Allocation: Randomized
Intervention model: Single Group Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Diagnostic
Keywords: EUS FNA; stylet; suction