Background: Lymphatic involvement may sometimes be detected in differentiated-type intramucosal cancer resected endoscopically during routine examination, but its incidence and clinical significance remain unknown.
Methods: We examined 300 endoscopically resected lesions obtained from 238 patients diagnosed with differentiated-type intramucosal gastric cancer. All sections were subjected to D2-40 monoclonal-based immunohistochemistry.
Results: The incidence of lymphatic involvement in differentiated-type intramucosal cancer was 2.0% (6/300). An incidence of 1.8% (5/279) was determined in lesions that were ≤ 3 cm in size and 2.2% (6/276) in those without an ulcer or ulcer scar. Of the six lesions presenting lymphatic involvement, three were determined to be histologically mixed with a predominance of differentiated type, while the other three lesions were pure differentiated type.
Conclusions: We determined that the incidence of lymphatic involvement in differentiated-type intramucosal cancer was 2.0%. To clarify the clinical significance of such lymphatic involvement, it is necessary to detect it with this incidence in mind and to gather and follow up the clinical courses of such cases.
Keywords: Adenocarcinoma; D2-40 monoclonal antibody; Gastrointestinal endoscopy; Stomach neoplasm.