Importance of Diagnostic Endoscopic Resection to Compensate Histological Discrepancy Between Endoscopic Forceps Biopsy and Resected Specimens in Superficial Gastric Neoplasms

Abstract

Background and Aims: Endoscopic forceps biopsy is a basic diagnostic modality for the histologic diagnosis of superficial gastric neoplasms. The histologic diagnosis determined that way, however, is not always representative of the whole lesion, and has a potential risk of underestimation of the grade of dysplasia. Recently, complete endoscopic resection (ER) can be established not only as a therapeutic tool but also as a definitive diagnostic tool. The aims of this study were to assess the limitation of forceps biopsy, and to investigate the diagnostic role of ER in superficial gastric neoplasms. Materials and Methods: From December 2006 to November 2008, a total of 195 patients with superficial gastric neoplasms detected by surveillance endoscopy were enrolled for this study. They underwent an endoscopic forceps biopsy and the subsequent ER (endoscopic mucosal resection or endoscopic submucosal dissection). We analyzed the clinical and endoscopic characteristics of the patients and compared the histologic results of forceps biopsy specimens with those of the ER specimens. Results: A total of 209 lesions of 195 patients were analyzed. Total histological discrepancy rate was 50.7% (50.3%, 85/169 lesions) in adenoma, 52.5%, 21/40 lesions in EGC). In 108 cases of low grade adenoma diagnosed by forceps biopsy, final diagnosis was changed after ER in 44 (40.7%) cases (20 high grade adenoma, 12 gastric cancer, 12 gastritis) (p<0.05). Among various endoscopic features, the size (>20 mm in diameter) and the surface color (red-colored lesion) of the lesion were significantly associated with the histologic discrepancy (p < 0.05). In 40 cases of EGC diagnosed by forceps biopsy, type of differentiation was changed in 20 cases (50%), and one EGC revealed high grade adenoma. These results make us reconsider ESD indication. Conclusions: The histologic discrepancy rate between the endoscopic forceps biopsy and ER specimens was as high as 50%, and endoscopic forceps biopsy is insufficient method to decide therapeutic plan in superficial gastric neoplasms. Therefore, superficial neoplastic lesions in the stomach should be completely resected by ER for complete diagnosis and definitive treatment.