Gefitinib Plus Standard Chemotherapy Versus Standard Chemotherapy In EGFR-mutation-positive Lung Adenocarcinoma After Progression On First-line Gefitinib

Objective With the development of economy, air pollution becomes more and more serious, lung cancer incidence and mortality in China has shown a rising trend. It is already very late when most lung cancer patients are found.They lost the chance of surgery and chemotherapy and radiotherapy is the main therapeutic method, but treatment effect of advanced lung adenocarcinoma patients is still not ideal. At present, tumor molecular targeted drugs are widely used in the treatment of cancer, with better effect and less adverse reactions. However, after 7-12 months of treatment, patients" disease progressed.The following treatment is still controversial. We aimed to assess the efficacy and safety of continuing gefitinib combined with chemotherapy versus chemotherapy alone in patients with EGFR-mutation-positive advanced lung adenocarcinoma with acquired resistance to first-line gefitinib.Methods Review the EGFR mutation positive lung adenocarcinoma patients on stage IIIB / IV in 66 cases of First Affiliated Hospital of Zhengzhou University from April 1, 2012 to April 1, 2014 who were treated with first-line gefitinib and showed progression.patients after acquired TKI resistance were followed by gefitinib combined with standard chemotherapy or standard chemotherapy alone. The efficacy and side effects between the two regimens were obserwed.Result The ovel remission rate of combined treatment group was 27%(n = 9) and standard chemotherapy group was 33%(11 cases). there was no significant difference(c2=0.287 P=0.789). Disease control rate of combined treatment group 28(85%) patients, the standard chemotherapy group and 79%(26 cases). Two groups of disease control rate difference is not statistically significant(c2=0.287 P=0.789). Median progression-free survival time 4.5 months(95% CI 3.19–5.81) in the combined treatment group and 4.4months(95% CI 2.91– 6.09) in the standard chemotherapy group, There were no significant difference in both groups. The median overall survival time in the combination therapy group(17.0 months) compared with standard chemotherapy group(14.1 months) is slightly longer. The difference of two groups of median overall survival time is significance(c2=4.001 P = 0.045). The most common adverse events of any grade were nausea(20 [66%] of 33 patients in the combined treatment group and 19 [58%] of 33 patients in the standard chemotherapy group) and decreased appetite(16 [48%] and 10 [30%]).The most common adverse events of grade 3 or worse were anaemia(3 [9%] of 33 patients in the combined treatment group and 1 [3%] of 33 patients in the standard chemotherapy group) and neutropenia(2 [7%] and 2 [7%]). 9(27%) of 33 patients in the combined treatment group and 7(21%) of 33 patients in the standard chemotherapy group reported serious adverse events.Conclution Assess the efficacy and safety of continuing gefitinib combined with chemotherapy versus chemotherapy alone in patients with EGFR-mutation-positive advanced lung adenocarcinoma with acquired resistance to first-line gefitinib. The following conclusions can be obtained:1.The two groups showed no significant difference in progression free; 2.The recent outcomes including efficiency, disease control rate and improve the quality of life also showed no significant difference; 3.The analysis of overall survival shows that the survival time of the combinationtherapy group is longer than standard chemotherapy group. 4.The two schemes has similar safety.So,continuation of gefitinib after disease progression on first-line gefitinib can prolong overall survival in patients who received platinum-based doublet chemotherapy as subsequent line of treatment.