Study On ALK Gene Mutation Status In Non Small Cell Lung Cancer Of The Wild Type EGFR

Objective:To Study of non-small cell lung cancer patients of anaplastic lymphoma kinase (anaplastic lymphoma kinase, ALK) fusion gene expression Conditions and clinical pathological features.Methods:We collected 289 patients’Non-small cell lung cancer paraffin embedding tissue from pathology department of Guangxi medical university affiliated tumor hospital from 2011.10 to 2014.12. Specimens of 289 cases of lung cancer cases are applied to detection of EGFR mutations by amplification block mutation system method. Test results can be divided into EGFR mutation type and EGFR of wild type in the two groups,and then detect the ALK expression With immune histochemical method (immunohistochemistory, IHC) (Ventana kit). And statistically analyzed data using χ2 test or Exact probabilities by SPSS21.0 statistical software, correlation analysis using spearman..Results:(1) The average age of the 289 cases of patients with non small cell lung cancer was 58.36 years old, Less than 60,152 cases, greater than or equal to 60,137 cases; 172 patients were male, accounting for 59.52%; female 117 cases, accounting for 40.48%; In the smoking history,179 cases with no smoking history, accounted for 61.94%,110 cases has a history of smoking, accounting for 38.06%; In the pathological type,231 cases of adenocarcinoma, 79.93%; Squamous cell carcinomas 34 cases (11.76%), adenosquamous carcinoma,9 cases (3.20%); Neuroendocrine carcinoma (2 cases, accounting for 0.69%; Carcinoid tumor in 1 case (0.35%), Sarcomatoid carcinoma 3 cases, accounting for 1.04%; Lymphatic carcinoma in 1 case (0.35%), Bronchioloalveolar carcinoma in 1 case (0.35%), Other 7 cases, accounting for 2.42%. In the clinical staging,68 patients at stage Ⅳ,89 cases in stage Ⅲ,42 cases in stage 11,90 cases at stage Ⅰ.(2) In 289 cases of non-small cell lung cancer specimens,128 cases of EGFR gene mutation was detected, mutation rate was 44.29%(128/289),56 cases of 128 cases of mutations exon 21 L858R mutations (43.75%),1 case of exon 21 L861Q mutations (0.8%),69 cases of 19 exons deletion (53.91%),1 case of 19 del+20T790m double mutations (0.8%),1 case of 20T790m+ L858R mutations (0.8%).(3) In 289 cases of non-small cell lung cancer specimens,13 cases EML4- ALK positive expression. EML4- ALK fusion gene in patients with positive and negative in age (P=0.072), sex (P>0.05), smoking (P>0.05), Pathological staging (P>0.05), tissue differentiation (P>0.05), with and without lymph node metastasis (P>0.05) difference had no statistical difference.(4) From the clinical features of 13 patients with EML4- ALK positive constitute the basis, see more at Young (76.92%), smoking (84.62%) and male (69.23%), adenocarcinoma (100.00%) patients.(5) 13 cases of patients with EML4- ALK positive EGFR (18-21 extra show son) 1 case for mutant, the other 12 cases were wild type. EML4 ALK and EGFR expression in patients with non-small-cell lung cancer (NSCLC) correlation analysis, showed a negative correlation between them (R=-0.160, P =0.007), the difference was statistically significant.Conclusions:1. The use of automatic immunohistochemical method (Ventana) for detection of ALK gene is a simple, inexpensive, standardized, simple interpretation method and can be a good quality control, it is suitable for clinical application.2. EML4-ALK fusion is a new molecular subtype of non-small cell lung cancer after EGFR gene, ALK gene was more common in young, not smoking, patients with adenocarcinoma, which provide a theoretical reference for the clinical practice in the screening of EML4-ALK mutation potential population3. ALK gene rearrangement and EGFR mutation was negatively correlated; ALK rearrangement can coexist with EGFR mutation.