Effects of gemcitabine and cisplatin chemotherapy in advanced non-small cell lung cancer patients with RRM1 low protein expression

Objective： The aim of this study was to observe the efficacy of gemcitabine combined with cisplatin （GP） in advanced non-smaU cell lung cancer （NSCLC） patients with low expression of ribonucleotide reductase 1 （RRM1） protein using immunohistochemistry. Methods： RRM1 protein expression in tumor tissue was detected by streptavidin-peroxidase （SP） method of immunohistochemistry. GP regimen （gemcitabine 1000-1250 mg d1, d8, cisplatin 75 mg/m2） was given to advanced NSCLC patients with low expression of RRM1 protein. Results： In the total of 40 patients, these patients with RRM1 low expression performing GP chemotherapy had a good response rate, the objective response rate （ORR） was 47.5% （95% CI, 32.02%- 62.98%）, and the disease control rate （DCR） was 72.5% （95 % CI, 65.44%-79.56%）. ORR is 45.45% （5/11） in the squamous cell carcinoma patients while 48.15% （13/27） in the adenocarcinoma patients. Conclusion： Supedor ORR and DCR were found in advanced NSCLC patients with low expression of RRM1 protein expression performing GP regimen.