Association between the HER2 Gene Status and the Efficacy of First-line Pemetrexed Combined with Platinum Chemotherapy in Patients with Advanced Lung Adenocarcinoma / 中国肺癌杂志

BACKGROUND@#Human epidermal growth factor receptor 2 (HER2) is one of the driver genes of non-small cell lung cancer (NSCLC). Several studies have shown that the efficacy of pemetrexed in HER2-mutant NSCLC is controversial. The aim of this study is to investigate the efficacy of pemetrexed combined with platinum chemotherapy in patients with HER2-mutant and HER2 wild-type lung adenocarcinoma.@*METHODS@#The clinical data of 106 cases of EGFR, ALK, ROS-1, KRAS, BRAF, RET and MET-negative patients with advanced lung adenocarcinoma patients who diagnosed by histopathology in the First Affiliated Hospital of Zhengzhou University were retrospectively reviewed. The relationships between HER2 gene status, clinical characteristics and response and progression-free survival (PFS) were analyzed.@*RESULTS@#All of the 106 patients' HER2 status were determined. HER2 mutations occurred in 32 cases (30.2%), no mutations in 74 cases (69.8%). HER2 mutations were common in young, non-smoking and female patients. All patients received first-line pemetrexed and platinum-based chemotherapy. The objective response rate (ORR) and disease control rate (DCR) of patients with HER2-mutant lung adenocarcinoma were significantly higher than those without HER2 mutations (40.6% vs 14.9%, χ²=8.464, P=0.004; 93.8% vs 68.9%, χ²=6.327, P=0.012), and the difference was statistically significant. According to univariate analysis, the PFS was significantly associated with the brain metastases, maintenance chemotherapy and HER2 gene status (P0.05). Cox multivariate analysis indicated that HER2 mutation was an independent positive prognostic factor of PFS (P=0.038).@*CONCLUSIONS@#HER2-mutant lung adenocarcinoma patients with first-line pemetrexed combined with platinum chemotherapy have greater clinical benefit than HER2 wild-type patients.

Characteristics of Epidermal Growth Factor Receptor with Rare Mutations in Non-small Cell Lung Cancer and the Effect of EGFR Tyrosine Kinase Inhibitors on Them / 中国肺癌杂志

BACKGROUND@#Adenocarcinoma is the most common type of lung cancer. It has been clinically evaluated that therapiestargeting against the epidermal growth factor receptor (EGFR) as the clinical standard first-line treatment. The response and outcome of EGFR-tyrosine kinase inhibitors (TKIs) in patients harboring common mutations in EGFR kinase domain (deletion in exon19 and L858R in exon 21) has been well demonstrated, but not in rare or complex mutations.@*METHODS@#A total of 150 patients that harbored rare or complex mutations in EGFR diagnosed by histopathology were included in this retrospective study. The clinical-pathological characteristics of all 150 patients as well as the response and progression-free survival (PFS) in 48 patients that received EGFR-TKIs in first/second/third line treatments weredescribed and analyzed.@*RESULTS@#Patients were divided into four groups based on the mutation types: single G719X point mutation in exon 18 (n=46, 30.7%), single L861Q point mutation in exon 21 (n=45, 30.0%), other single rare mutation (n=14, 9.3%) and complex mutations (n=45, 30.0%). The result indicated thatthere was no correlation of EGFR mutation typeswith other parameters such as gender, age, clinical stage, pathology and smoking history. For the 48 patients that received EGFR-TKIs treatment, there were no significant differencesamong 4 groups in terms of objective response rate (ORR) and disease control rate (DCR) (54.5% vs 30.0% vs 0.0% vs 35.7%, χ²=3.200, P=0.34; 90.9% vs 85.0% vs 66.7% vs 92.9%, χ²=2.162, P=0.59). The median progress-free survival (mPFS) was 11.0 months (95%CI: 4.4-17.6), and in each group of different EGFR mutation types are 15.8 months (95%CI: 9.5-22.2), 8.0 months (95%CI: 5.1-11.0), 4.9 months (95%CI: 1.4-8.4) and 23.1 months (95%CI: 15.8-30.4)(χ²=7.876, P=0.049).@*CONCLUSIONS@#The efficiency of targeting EGFR-TKIs on different types of rare or complex mutations was heterogeneous. The PFS may be better in patients that harbored complex mutations than those with single rare mutations. Further studies with larger sample size are necessary. Moreover, to discover novel therapeutic targets and develop new drugs are imminentfor those patientswith no response to the existing treatments.