The Application Of Eus In The Diagnosis And Therapy Of Pancreatic Cancer

Objective: To evaluate the performance of EUS-FNA combined with K-ras mutation analysis in the diagnosis of pancreatic cancer.Methods:(1)We collected 28 cases of pancreatic cancer of cancerous and non-cancerous tissue specimens,and all specimens were detected K-ras mutation by PCR.(2)EUS-FNA was performed in 74 patients with pancreatic lesions from September 2014 to July 2015.All EUS-FNA specimens were detected K-ras mutation by PCR and dd PCR.(3)EUS-FNA was performed in 75 patients with pancreatic lesions,and we collected the EUS-FNA and serum specimens from August 2015 to May 2016.All specimens were detected K-ras mutation by PCR and dd PCR.Result:(1)The rate of K-ras mutations was 82.1% in the cancerous tissue and the most frequent subtype was G12D(39.3%).K-ras mutations were detected in only 3 non-cancerous tissue(10.7%),including 2 G12D(7.1%)and 1 G12R(3.6%).(2)In the 149 patients with pancreatic lesions that we collected EUS-FNA samples,105 patients were diagnosed with pancreatic cancer.K-ras mutations were detected in 62.9% of the pancreatic cancer by PCR and 81.0% by dd PCR(P=0.004).The accuracy of EUS-FNA,EUS-FNA combined with K-ras mutations analysis by PCR,and EUS-FNA combined with K-ras mutations analysis by dd PCR was 75.8%,83.9%,88.6%,respectively.The accuracy of EUS-FNA combined with K-ras mutations analysis by dd PCR was higher than EUS-FNA(P<0.0001).The difference between EUS-FNA and EUS-FNA combined with K-ras mutations analysis by PCR was no statistically significant(P=0.274).(3)In the 75 patients with pancreatic lesions that we collected EUS-FNA samples and the serum samples,57 patients were diagnosed with pancreatic cancer.All the samples were detected with K-ras mutations by dd PCR.The rate of K-ras mutations was 71.9% in EUS-FNA samples and 35.1% in the serum samples.The accuracy of K-ras mutations analysis in ct DNA by dd PCR for the diagnosis of pancreatic cancer was 48%,and it was lower than EUS-FNA(P<0.0001)and EUS-FNA combined with K-ras mutations analysis by dd PCR(P<0.0001).(4)For the 105 patients diagnosed with pancreatic cancer,a K-ras G12 D mutation was a negative prognostic factor.The median survival was decreased in patients with G12 D mutation compared with WT,G12 V mutation and G12 R mutation.For the 57 patients diagnosed with pancreatic cancer who we collected the serum samples,G12 D mutation reminded a negative prognostic factor.Conclusion:(1)EUS-FNA combined with K-ras mutations analysis by dd PCR could improve the accuracy in the diagnosis of pancreatic cancer.(2)If K-ras mutations were detected in benign pancreatic lesions,close clinical follow-up would be warranted.(3)The diagnosis efficiency of K-ras mutations analysis by dd PCR in ct DNA was limited,and the liquid biopsy could not take the place of EUS-FNA.(4)The K-ras G12 D mutation was a negative prognostic factor for the patients with pancreatic cancer.Aims: To study the feasibility,safety and efficacy of endoscopic ultrasonography(EUS)-radiofrequency ablation(RFA)for unresectable pancreatic cancer.Materials and methods: A retrospective analysis was performed in 8 cases with unresectable pancreatic cancer underwent EUS-RFA between November 2013 and June 2016.The procedure was performed using an Olympus linear echoendoscope platform on Alpha 5,EU-ME1 or SU-8000.RFA was applied with a novel monopolar RFA probe placed through a 22 G fine needle aspiration(FNA)needle.The RFA probe was connected to the RITA 1500 X radiofrequency generator.Power in the generator was set to 5-10 watts.RFA power was applied to coagulate tissue for 90 seconds at one site.Results: Eight patients with a median age of 65.5 years,including 3 female and 5 male,were subjected to EUS-RFA.The post procedure imaging in 1 month showed the decrease of lesions in 2 patients,and 4 patients showed the decreased serum CA19-9 level.In particular,one patient had increased of the tumour apparent diffusion coefficient(ADC)and had significant survival benefit.No major complications were observed before their hospital discharge.One patient had mild abdominal pain that resolved within 24 hour.Conclusions: The present series showed that EUS-RFA of unresectable pancreatic cancer was well tolerated.The technical success of EUS-RFA was achieved and the short-term efficacy(tumor response)was observed by evaluating the tumor size and CA19-9 level.A multiple-round ablation with optimal RFA energy would bring the maximal benefit to those patients with locally advanced pancreatic cancer.