Proliferative activity of gastric cancer assessed by immunostaining for proliferating

The growth activity of 107 gastric carcinomas was assessed by immunohis‐tochemical staining for formalin‐fixed, paraffin‐embedded tissue with a monoclonal antibody against proliferating cell nuclear antigen (PCNA). When the tumor doubling times (Tds) of 10 patients were estimated from the serum levels of carcinoembryonic antigen and carbohydrate antigen 19–9, there was an inverse correlation between the Tds and PCNA labeling index (LI) at P = 0.055. Flow‐cytometric analysis was carried out by double staining for PCNA and DNA using fresh materials from 14 patients. The PCNA‐positive cell fraction revealed by flow cytometry showed a good linear correlation with PCNA LI in routinely stained tissue. The LI of well‐differentiated adenocarcinoma was significantly higher than that of the poorly differentiated type. When the LI was analyzed in well‐ or poorly differentiated adenocarcinoma, the value was significantly higher in the well‐differentiated type with hepatic metastasis and in the poorly differentiated type with lymph node metastasis. © 1993 Wiley‐Liss, Inc.