Underestimation of endoscopic size in large gastric epithelial neoplasms

Abstract

Background/Aims: Endoscopic submucosal dissection (ESD) is an effective method for resecting gastric adenomas and adenocarcinomas. A significant discrepancy was observed between endoscopic and pathological sizes in samples obtained from patients undergoing ESD. This study elucidates the factors affecting size discrepancy after formalin fixation.Methods: The records of 64 patients with 69 lesions were analyzed, including 50 adenomas and 19 adenocarcinomas. Data on location, gross shape, histology, and size after fixation in formalin were collected.Results: The mean size of the resected specimen appeared to decrease after formalin fixation (37.5 mm prefixation vs. 35.8 mm postfixation, p<0.05). The mean long axis diameter of the lesions was 20.3±7.9 mm prefixation and 13.4±7.9 mm postfixation. Size differences in lesions smaller than 20 mm were significantly greater than those in lesions larger than 20 mm (7.6±5.6 mm vs. 2.5±5.8 mm, p<0.01). In multivariate analysis, a tumor size of ≥20 mm was found to be an independent factor affecting size postformalin fixation (p<0.05).Conclusions: The endoscopic size of lesions before ESD may be underestimated in tumors larger than 20 mm in size. Therefore, increased attention must be paid during ESD to avoid instances of incomplete resection.

Need for careful endoscopic evaluation of large gastric neoplasms before endoscopic submucosal dissection

“…Therefore, it is necessary to observe lesions very carefully when performing endoscopic submucosal dissection for large lesions because of the risk of size underestimation. As Song et al 9 mentioned, the small sample size, analysis of the long axis alone, and subjectivity due to measurement of the lesion size by a single endoscopist were the limitations of this study. The lack of analysis of undifferentiated-type cancers is another limitation.…”

“…6 Recently, new methods including novel endoscopic systems and artificial intelligence have been reported to be helpful in measuring lesion size and delineating their margins. 7,8 In the current issue of Clinical Endoscopy, Song et al 9 prospectively evaluated the size discrepancy between pre-and post-formalin fixation and the risk factors for underestimation of lesion size. They included 69 lesions from 64 patients diagnosed with gastric adenoma or adenocarcinoma, and analyzed the factors influencing size discrepancy.…”

“…In the current issue of Clinical Endoscopy , Song et al 9 prospectively evaluated the size discrepancy between pre- and post-formalin fixation and the risk factors for underestimation of lesion size. They included 69 lesions from 64 patients diagnosed with gastric adenoma or adenocarcinoma, and analyzed the factors influencing size discrepancy.…”

Transcecal endoscopic appendectomy for management of complex appendiceal polyps extending into the appendiceal orifice

“…Appendix and polyp sizes were collected from the pathology report. Using post formalin fixation size is associated with underestimation of the actual length of the appendix as the result of tissue shrinkage [16,17]. However, because the majority of the polyps extended into the appendiceal lumen, in order to maintain consistency in reporting the diameters, the decision was made to use the post fixation sizes.…”