The diagnostic role of endoscopic submucosal dissection for gastric lesions with indefinite pathology

Objective. Endoscopic forceps biopsy is a fundamental modality for the histologic diagnosis of gastric neoplasms. However, the pathologic findings are not always concordant with the endoscopic interpretations. Currently, repeat endoscopic biopsy is the only way to manage lesion of indefinite pathology such as Category 2 according to the revised Vienna classification. We aimed to elucidate the role of endoscopic submucosal dissection (ESD) in clarifying the final pathologic diagnosis. Method. Among the 2304 gastric ESD cases, a total of consecutive 30 patients with 31 lesions (1.3%) that had a forceps biopsy with indefinite pathology discrepant from the endoscopic findings underwent endoscopic submucosal dissection (ESD) for confirmative diagnosis and treatment. Results. The final pathologic diagnoses of the ESD specimens were as follows: low-grade dysplasia in 3 patients (9.7%); high-grade dysplasia in 2 patients (6.5%); adenocarcinoma in 15 patients (48.4%); and a benign lesion in 11 patients (35.5%). Cases with adenocarcinoma included nine well-differentiated lesions, four moderately differentiated lesions, and two lesions with signet ring cell carcinoma. The complete en bloc resection rate for neoplastic lesions was 95.0%, and the incidence rates of ESD-related bleeding and perforation were 5.0% and 5.0%, respectively. Conclusion. ESD can be considered an effective and safe alternative therapeutic and diagnostic tool for gastric lesions in cases where the forceps biopsy pathology is discrepant from the endoscopic findings. The overall final neoplastic diagnosis rate after ESD was 64.5%, and ESD should be performed for lesions with red coloration and friability.