The usefulness of serum tumor markers in monitoring of response to systemic chemotherapy in patients with gastric cancer: Ca 72-4 and CEA.

Abstract

e14580 Background: Evaluation of response after chemotherapy in patients with gastric carcinoma is sometimes difficult. The authors investigated whether changes in the serum levels of two tumor markers – CA 72-4 and CEA can be used to predict the clinical outcome after chemotherapy. Methods: Eighty patients with advanced or recurrent gastric carcinoma were treated with DOS (docetaxel + oxaliplatin + TS-1) or DS (docetaxel + TS-1). The serum levels of CEA and CA 72-4 were measured prior to and after chemotherapy. Responders were defined as those in whom abnormal serum levels of tumor markers decreased to at least 50% of the pretreatment levels. We assessed treatment responses by the computed tomography and serum tumor marker levels, and compared the survival rates of two assessment modalities. Results: The response assessed by serum CA 72-4 level was significantly related with the response by imaging study, but that by serum CEA level was not. On CT assessment the median durations of survival for 28 responders and 38 non-responders were 706.3 days and 332.5 days, respectively. And on serum CA 72-4 assessment, they were 435.9 days in 28 responders and 276.8 days in 13 non-responders with statistically significant difference, but there was no significant difference of survival on serum CEA assessment . Conclusions: The serial measurement of the serum CA 72-4 level may be a useful tool of monitoring response and predicting the prognosis after chemotherapy for patients with gastric cancer of increased pretreatment level.