Immunohistochemical evaluation of lymph node micrometastases from gastric carcinomas.

Abstract

The clinicopathologic significance of micrometastases to lymph nodes, consisting of a single carcinoma cell or a small cluster of carcinoma cells and confirmed only by special staining, was evaluated in patients with gastric carcinoma. The authors studied 2446 lymph nodes removed during surgery for 109 cases of gastric carcinoma, including Stages I, II, III and IV. Tissue preparations were stained with hematoxylin and eosin (H&E), Alcian blue in combination with periodic acid-Schiff stain, and antibodies against cytokeratin and carcinoembryonic antigen (CEA). Metastases were confirmed in 230 lymph nodes (9.4%) stained with H & E, and an additional 201 lymph nodes (17.6%) had micrometastases identified only by immunostaining for cytokeratin (197 lymph nodes) and/or CEA (66). Carcinomas with micrometastases had significantly worse prognoses at Stage II. Between the two histologic types of gastric carcinoma, the diffuse type had more micrometastases than the intestinal type. The findings of this study indicate that the presence of micrometastases in lymph nodes is an indispensable factor in determining the prognosis of gastric carcinoma patients.