Efficacy and toxicity of pemetrexed or gemcitabine combined with cisplatin in the treatment of patients with advanced non-small cell lung cancer

Background and objective Due to the various inter-individual differences in the biological characteristics of tumor cells, as well as issues on the efficacy, adverse reactions, and defects of existing drugs, we compared the clinical efficacy and toxicity of pemetrexed and gemcitabine combined with cisplatin for the treatment of previously untreated advanced non-small cell lung cancer (NSCLC). Methods 251 patients were randomly divided into pemetrexed combined with cisplatin group (PP group) with 127 cases and gemcitabine combined with cisplatin group (GP group) with 124 cases. PP group received pemetrexed 500 mg/m² iv infusion dl and cisplatin 75 mg/m² iv infusion dl, whereas GP group received gemcitabine 1,000 mg/m² iv infusion dl,8 and cisplatin 75 mg/m iv infusion dl. The treatment cycle was once every three weeks. In addition, folic acid, vitamin B₁₂, and dexamethasone were administered in both groups. Results The total clinical effective rates in PP group and GP group were 25.20% and 17.74%, respectively. The total efficiencies of non-squamous cell carcinoma were 27.62% and 16.00%. The tumor progression duration in these two groups was 6.5 and 5.6 months, respectively. The median survival time in the two groups was 16.9 and 17.0 months, respectively, with 59.62% and 65.87% survival rates of 1 year and 27.28% and 27.93% survival rates of 2 years, respectively. The total efficacy of non-squamous cell carcinoma in the PP group was significantly higher than that in GP group. The results were statistically significant. However, there were no significant differences in total response rates, tumor progression duration, and median survival rates of 1 and 2 years. The rate of adverse reactions, including white blood cell reduction, lower platelet count, lower hemoglobin, and hair loss in the PP group was significantly lower than that in the GP group. The results were statistically significant. Conclusion The clinical efficacy of pemetrexed and gemcitabine combined with cisplatin for the treatment of previously untreated advanced NSCLC was roughly the same, but the adverse reactions decreased significantly in the PP group compared with those in the GP group. Therefore, pemetrexed combined with cisplatin can be used as a safe and effective drug for clinical first-line treatment for previously untreated NSCLC.