Detection of circulating stage III–IV gastric cancer tumor cells based on isolation by size of epithelial tumor: using the circulating tumor cell biopsy technology

BACKGROUND: To explore the correlations between circulating tumor cells (CTCs) and the patients’ clinical characteristics and other tumor markers in stage III–IV gastric cancer patients, and assess the value of CTCs as a predictor of the efficacy of chemotherapy. METHODS: CTCs were measured in 42 patients with stage III–IV gastric cancer using the isolation by size of epithelial tumor (ISET) method. We analyzed the correlations between the number of CTCs, patients’ pathological characteristics and peripheral blood tumor markers. Then divided the 42 patients into two groups, the progressive disease group (PD group) and the disease control rate group (DCR group), according to the efficacy of chemotherapy, and analyzed the differences in the CTC expression between the two groups. RESULTS: The threshold number of CTCs was closely related to the clinical stage (P=0.044), and was positively correlated with the value in U/mL of CA724 (P<0.05). The treatment response to cytotoxic chemotherapy in the high threshold number group was significantly poorer. CONCLUSIONS: CTCs technology based on ISET method has a high detection rate. CTCs are promising predictor for the evaluation and prediction of treatment responses in stage III–IV gastric cancer.