Application of monoclonal antibodies to histologic diagnosis of gastric cancers.

Abstract

Histologic diagnosis of poorly differentiated gastric adenocarcinomas by conventional hematoxylin-eosin (HE) staining is often limited by the quality of gastroendoscopic biopsy specimens. In this study we attempted to identify gastric cancer cells in biopsy specimens and ascites of gastric cancer patients using the gastric cancer reactive monoclonal antibodies S202 and S74. Twenty-four of 25 specimens shown to contain cancer cells by HE staining were stained positively by monoclonal antibody S202. In contrast, 3 of 16 specimens that were diagnosed as not including cancer cells by HE staining was stained positively by S202. The possibility that cancer cells in the biopsy specimens were not detected by HE staining cannot be ruled out. Cancer cells in ascites of patients diagnosed with carcinomatous peritonitis by Papanicolaou staining were stained positively by monoclonal antibody S74. From these results, we conclude that monoclonal antibodies S202 and S74 may be useful supplemental agents for the diagnosis of gastric cancer.