Detection of multidrug-resistant, gene-related proteins for postoperative individualized chemotherapy of gastric cancer.

Abstract

156 Background: Postoperative adjuvant chemotherapy was beneficial for some patients,however, it may increase the treatment burden and reduce the immunity of other patients. Screening appropriate patients based on molecular markers for individualized adjuvant chemotherapy was necessary. Methods: Between June 2002 to June 2004, 119 patients who underwent radical gastrectomy were retrospectively analyzed. 61 patients had adjuvant chemotherapy based on platinum and 5-FU for 4 to 6 cycles. ToPo II negative, MRP positive and GST-π positive were regarded as three risk factors which may be associated with chemotherapy resistance and poor prognosis. Patients were divided into two groups: high-risk group (≥2 risk factors) and the low-risk group (<2 risk factors), and the tumor recurrence and patients’ survival time of the two groups were analyzed. Results: The average recurrence time of the low-risk group was significantly longer than that of the high-risk group (21.29 ± 11.10 VS 15.16 ± 8.05 months ,p<0.01).The 3-year and 5-year survival rate of the high-risk group was 57.4% and 42.6%, however, it had no significant difference compared to 66.2% and 58.5% of the low-risk group (P> 0.05). In the high-risk group, the 3-year survival rate of patients with/without chemotherapy were 62.1% and 52.0%, 5-year survival rates were 44.8% and 40.0%, but the difference was not statistically significant (P> 0.05). In the low-risk group, the 3-year survival rate of patients with/without chemotherapy were 81.2% and 51.5%, 5-year survival rates were 71.9% and 45.5%, and the difference was statistically significant (p<0.05). Conclusions: Combined determination of MDR-related proteins ToPo II, MRP and GST-π may be prospectively valuable for optimizing the chemotherapy regimes, and further predicting the outcomes of gastric cancer patients.