CT-guided Aspiration Lung Biopsy For EGFR Gene And ALK Gene Mutation Analysis Of Lung Cancer

Objective:To clear the detection rates and the positive rates of CT-guided aspiration lung biopsy for EGFR gene and ALK gene mutation analysis, analyze the relationship between gene mutation and clinical characteristics, improve related factors of gene detection rate.Methods:We collected the clinical data of 50 patients with lung cancer and their CT guided fine needle biopsy specimens and 200 patients with lung cancer and their coarse needle biopsy specimens. We use the Scorpions ARMS method to detect EGFR gene and Ventana ALK (D5F3) immunohistochemical method to detect ALK expression of biopsy specimens. Then we compared the clinical and pathological features of patients with positive and negative gene mutation, and analysised the relationship between tumor cell number and proportion and the biopsy specimen detection rate.Results:It was found that EGFR gene mutation rate was 41.2%(103 out of 250)in biopsy specimens of NSCLC patients,including exon 19 deletion, exon 21 L858R mutations and so on; ALK gene mutation rate was 6%(15 out of 250). Among patients with EGFR gene mutation rate was significantly higher in females than male patients (62.1%, 37.9%, P<0.01); and significantly higher in patients without smoking than smoking patients (56.2%,25%, P<0.01).No correlation between age> stage and gene mutations was found. EGFR gene mutation rate of Adenocarcinoma (56.6%, P< 0.01) was obiviously higher than other types of lung cancer. There was no relationship between ALK gene expression and factors such as gender, age, pathological differentiation (P> 0.05); ALK mutation cases were no history of smoke and all were adenocarcinoma.EGFR gene detection rate was 83.2%(208 out of 250), detection rate of coarse needle biopsy was higher than the needle (91%,52%, P< 0.01), and the positive rate is also higher than fine needle (45.5%,24%, P< 0.01). ALK protein immunohistochemical detection rate was 87.2%, and the coarse needle biopsy needle detection rate was higher than the needle (91%,72%, P< 0.01), but no difference (P> 0.05)in the positive rate between coarse needle biopsy and needle. The detection rate was associated with tumor cell number (P< 0.05), and had nothing to do with the proportion of tumor cells (P> 0.05).Conclusions:The detection rate of EGFR gene and ALK gene in 250 cases were 83.2% and 87.2% respectively.The detection rate of coarse needle biopsy was higher than needle. In view of needle detection rate still not low, patients with fine needle puncture indication is better to choose needle puncture. The detection rate was associated with tumor cell number and had nothing to do with the proportion of tumor cells.The detection rate will be higher when tumor cells number more than 50.