Objective: To explore the clinical values of detecting drug related molecules excision repair cross complementing 1 (ERCC1) and top-isomerase I (TOPO I) in individualized therapies of metastatic colorectal cancer.
Methods: From June 2009 to December 2011, 90 patients at Huadong Hospital with metastatic colorectal cancer were randomly separated into 2 groups after operation. Each group had 45 patients without difference in gender, age or TNM stage. The expressions of ERCC1 and TOPO Iin cancer tissues were detected by immunohistochemical staining. The testing group received individualized chemotherapies following the expression results while the control group had random chemotherapies. The survival difference between two groups was analyzed by log-rank test and Kaplan-Meier analysis. And curative effect was analyzed by χ(2) or Fisher's analysis.
Results: The expressions of ERCC1 and TOPO I had no statistical significance between two groups (both P > 0.05). In the testing group, the median survival time was 281 days and the beneficial ratio 51.1% (23/45) versus 246 days and 44.4% (20/45) respectively in the control group. The inter-group comparisons of survival (P = 0.235) and curative effect (χ(2) = 0.04, P > 0.05) showed no statistical significance. In the estimated drug tolerated group (ERCC1 high expression or TOPO I low expression), the median survival time was 196 days and the beneficial ratio 4/14 versus 304 days and 51.3% (39/76) in the estimated drug sensitive group. The inter-group comparisons of survival and curative effect (both P < 0.05) had statistical significance. The median survival time and beneficial ratio significantly increased in estimated drug sensitive group than those in estimated drug tolerated group.
Conclusions: The expression of drug related molecule in colorectal cancer tissue is significantly associated with curative effect in patients. Patients with down-regulated ERCC1 on Oxaliplatin or up-regulated TOPO Ion Irinotecan have longer survival and better curative effect. And chemotherapies guided by drug related molecule detection may boost curative effects in metastatic colorectal cancer.