Peritoneal carcinoembryonic antigen level for predicting locoregional and distant spread of gastric cancer

Purpose. Peritoneal recurrence is not an uncommon cause of death after surgery for gastric cancer, even after surgery with curative intent. This indicates that there is undetected residual disease in the peritoneal cavity. We conducted this study to determine the value of peritoneal and serum carcinoembryonic antigen (CEA) levels and peritoneal washing cytology in predicting the locoregional and distant spread of gastric cancer. Methods. We prospectively evaluated 70 consecutive patients with gastric cancer by measuring peritoneal CEA (pCEA) and serum CEA (sCEA) levels and peritoneal washing cytology results, and studying their effect on the histopathologic properties. The effect of the pCEA level on disease-free survival (DFS) and overall survival (OS) was also evaluated in patients treated with curative intent. Results. Twenty-one (30%) patients had sCEA levels > 10 ng/ml, whereas 25 patients (35.7%) had pCEA levels > 10 ng/g protein and 26 patients (37.1%) had positive cytology. The pCEA levels were significantly higher in patients with hepatic metastases (P = 0.034), or serosal (P = 0.028), and peritoneal (P = 0.026) involvement, whereas the sCEA levels were significantly higher only in patients with hepatic metastases (P = 0.04). Similarly, positive cytology was mainly detected in patients with hepatic metastases (P = 0.004). The pCEA levels significantly affected DFS (P = 0.002) and OS (P = 0.01) in 34 patients treated with curative intent. Conclusion Since pCEA levels are more useful for predicting locoregional recurrence, their measurement during surgery may help plan the most appropriate surgical strategy and adjuvant therapy.