Biopsy Tissue Retrieval Rate In Patients Undergoing Barrett'S Esophagus Surveillance

Introduction: Barrett's esophagus (BE) surveillance protocols are limited by 1) sampling error from relative small tissue area interrogated by biopsies, 2) interpretation error from interobserver variability in diagnosis and 3) processing error from potential loss of tissue from biopsies. Tissue obtained with biopsies can potentially become dislodged during retrieval through the instrument channel's valve. We are unaware that tissue retrieval rate has previously quantitated though loss of tissue has been noted. Aim: To determine biopsy tissue retrieval rate in patients undergoing BE surveillance. Methods: Patients undergoing surveillance for BE were prospectively consented for this study. All patients underwent Seattle protocol with four quadrant biopsies taken every 1 to 2 centimeters with a large capacity forceps using an Olympus GIF HQ190 or GIF 180 endoscope. To determine loss of BE tissue post procedure, the instrument channel's cap was removed and brushed for biopsy material. Amount of material obtained from the cap was recorded. Biopsy samples found in the cap were not submitted for histologic processing. Results: 56 patients were enrolled in the study with a mean (range) age of 72.2 (4990) of which 88% were male. 48 patients had short segment BE (3cm or less) while 8 patients had long segment BE (4cm or greater). We estimated the total number of biopsies obtained based on BE segment length to be 1124. Biopsy material was found in the instrument channel's cap in 4 patients, corresponding to 7.1% of cases. The biopsy tissue retrieval rate was calculated to be 99.7%. Conclusion: This preliminary study shows a high (99.7%) tissue retrieval rate in BE surveillance protocols. Tissue sample loss is a rare occurrence and should not adversely affect diagnostic yield.