[Immunocytologic detection of micro-metastatic cells in patients with gastrointestinal tumors]

The success of surgical treatment of gastric-, colorectal- and pancreatic cancer is often limited due to local recurrence, the development of metastases or peritoneal carcinosis by cells which have been seeded already at the time of operation. Immunocytological methods enable the detection of disseminated cancer cells before their clinical manifestation as demonstrated by this study. Lavage samples from the peritoneal cavity and bone marrow samples from 147 patients with an adenocarcinoma of the stomach, colon and pancreas were investigated with a panel of six different monoclonal antibodies against tumor-associated antigens (CEA, CA-19-9, 19-1A, C-54-0, Ra96) and cytokeratin, respectively. Additionally, 43 patients with benign diseases were investigated as a control group. Micrometastatic cells were detected either in the bone marrow or the peritoneal cavity in 51% of the cancer patients (gastric cancer: 51%, colorectal cancer: 40%, pancreatic cancer: 72%). The occurrence of stained cells in the peritoneal cavity and bone marrow samples correlated with the tumor stage and showed even in about 30% of patients with a stage I tumor positive bone marrow and/or peritoneal cavity samples. No unspecific reactions were found in the control group. The 2-year follow up shows a significant correlation between tumor cell detection and the survival. Our study strongly indicates a clinical benefit of this method in adjuvant therapy concepts.