Analysis Of 13 Squamous Cell Lung Cancer Patients Harboring EGFR Gene Mutation

Background:Squamous cell lung carcinoma (SQCLC) is the second most frequent histological subtype of non-small cell lung cancer (NSCLC), accounting for approximately 30% of all NSCLC. However, The rate for the Epidermal Growth Factor Receptor (EGFR) gene mutation in SQCLC is only 2.7%, which is much lower than that in lung adenocarcinoma. The National Comprehensive Cancer Network (NCCN) 2016 guidelines for NSCLC treatment stated that EGFR mutation analysis should be recommended for patients with SQCLC, mainly nonsmoker and patients with lung adenocarcinoma. Recent research founded that the rate of EGFR gene mutation in Chinese NSCLC patients is higher, as Asian patients with NSCLC has been found to have a higher incidence of the EGFR gene mutation. The first generation EGFR-TKIs monotherapy have been proven to be effective for treating NSCLC cases with EGFR gene mutation.Purpose:To calculate out the response rate and survival benefit of the East Asia SQCLC patients with EGFR sensitive mutation using the EGFR-TKIs monotherapy, and analyse their clinical characteristics and the reason for their lower results compare with the adenocarcinoma patients. To give advices to the selections of EGFR testing for SQCLC patients.Method:A case report of a SQCLC patient with EGFR gene mutation and analysis of 13 SQCLC patients harboring EGFR mutation; retrieval reported similar cases of SQCLC patient with EGFR gene mutation that published in the database of CNKI, Pub-med, CBM, at home and abroad from 2000 to 2011; analysis of RR, PFS and OS of the EGFR-TKIs mono-therapy in those patients and make a comparison with our research results.Results:1. The case reported in this article was diagnosed with right lung cancer in Dec 2011. Then Lobe resection and adjuvant chemotherapy was performed. This patient relapsed in May 2012 and received EGFR mutation analysis. Mutation in exon 21 of EGFR gene (L858R) was found. Then target therapy with erlotinib (150mg qd) was given and efficacy evaluation was PR during after 2 months treatment. The PFS was 4.25 months. After progression, the patient ceased the target therapy and receive traditional chemotherapy. However, the cancer could not be control and the patient died in Feb 2013.2. Collecting 13 SQCLC patients harboring EGFR mutation with the median age of 51.2. The female accounts for 62% and the smoker 77%. Their median PFS is 4.25 months and median OS is 12.0 months.Conclusions:1. The studies of EGFR gene mutation in SQCLC(only retrospective analyses and case reports can be seen so far) were mainly performed in East Asia, with fewer cases.2. In East Asia, the EGFR mutation rate of the SQCLC group is 5.4%-20.3%, and the 21-L858R is common but this group has a lower response rate, which is similar to the whole SQCLC group.3. It is necessary to test EGFR mutation in selected SQCLC group. And the characteristics of small biopsy, non-smokers, East Asians may suggest the existence of EGFR sensitive mutation4. After EGFR-TKI treatment, the ORR of the EGFR sensitive mutation SQCLC group is 25%-45%(average 31.6%); median PFS is 1.4-8.0 months (average 3.92months); median OS is 6.1-18.4 months (average>13.6months). The survival time of our case is much less than this result, which may explained by the improper arrangement of the treatment strategy, the equivocal staging before initial management and the psychological factor of the patient.5. In our own retrospective analysis, the OS is a little lower than the former result(>13.6 months), the reason for this may be that:some patients didn’t reach the end point of the follow-up, and the substandard treatment.