Clinical significance of CA125 and CA72-4 in gastric cancer with peritoneal dissemination.

Background: Serum tumor markers have been shown to correlate with the clinical status of patients with advanced gastric cancer. However, the clinical significance of each tumor marker in patients with peritoneal dissemination has not been fully verified.

Methods: Four serum markers, carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, CA125, and CA72-4, were periodically measured in 102 patients with peritoneal dissemination who received combination intravenous and intraperitoneal chemotherapy. The initial values at diagnosis and after treatment were analyzed in association with clinicopathological factors, response to chemotherapy, and overall survival.

Results: The sensitivities of CEA, CA19-9, CA125, and CA72-4 for peritoneal metastasis at the initial diagnosis were 19, 36, 46, and 45%, respectively. The CA125 level was significantly correlated with the degree of peritoneal dissemination and the existence of malignant ascites. Patients with ovarian metastasis showed significantly higher levels of CA72-4. The median survival time of patients with an elevated CA125 level was significantly shorter than that of patients with a normal CA125 level (36.7 vs. 16.6 months, p < 0.001). Multivariate analysis showed that the degree of peritoneal metastasis and an elevated CA125 level were independent prognostic factors. Normalization of the CA125 level after 3 courses of chemotherapy was correlated with reduced ascites and improved survival.

Conclusions: Serum CA125 and CA72-4 are clinically useful markers in diagnosis, evaluating the efficacy of chemotherapy, and predicting the prognosis of patients with peritoneal dissemination. From an academic point of view, periodic measurements of these markers are warranted in gastric cancer patients with possible peritoneal dissemination.