Cytological and histological analysis of samples obtained by endoscopic ultrasound guided fine needle aspiration / 中华消化内镜杂志

Objective To evaluated diagnosis yield of cytological and histological analysis of endoscopic ultrasound guided fine needle aspiration (EUS-FNA).Methods A total of 43 patients who were clinically diagnosed as having mediastinal lesions,retroperitoneal lesions or pancreatic lesions by CT were recruited to the study.EUS-FNA was performed with standard 22G needle.Specimens were placed in formalin for histological analysis,and residual materials were prepared for cytologic analysis.Results Lesions were located in the mediastinum (n =9),the retroperitoneum (n =1),and pancreas (n =33).Cytologic diagnoses included malignancy (n =22),suspicious malignancy (n =2),atypical cell (n =3),absence of malignancy (n =16).Histologic diagnoses included malignancy (n =30),suspicious malignancy (n =1),sarcoidosis (n =2),chronic inflammation (n =10).The positive rates,sensitivities and accuracies of cytology and histology were 51％,59％,65％ and 74％,81％,84％,respectively.Conclusion The positive rate,sensitivity and accuracy of histology of EUS-FNA is superior to cytology.

Establish of the orthotopic human pancreatic cancer model in mice and high frequency probe of endoscopy ultrasonographic monitoring / 中华胰腺病杂志

Objective To establish the orthotopic human pancreatic cancer model in mice and study the method to detect the tumor growth. Methods Human pancreatic cancer cell lines SW1990 in logarithmic phase was made into cell suspension and in situ injected into the envelope of pancreatic tail of BALB/c nude mice. High-frequency endoscopy ultrasound was used to observe the growth of tumor mass and its imaging characteristics were studied. Results 20 nude mice were successfully implanted, and 1 died 25 h after implantation. 14 days after implantation, the tumor of pancreatic cancer on EUS was (8.09 ± 2.61) mm3, the tumor appeared as homogeneous hypoechoic mass with clear boundary, and envelope as well as sound halo was present, and the shape was regular; there was low speed circular vasculature signal in around 30% of tumor.The tumor size increased to (12.40 ± 3.51)mm3, and the shape of 70% tumor was irregular, and some appeared as lobulated, and the tumor appeared as heterogeneous hypoechoic mass, no necrosis or liquefaction was found 28 days after implantation. There was low speed circular vasculature signal in around 70% tumors.Conclusions The orthotopic pancreatic cancer model in nude mouse can be established by in situ injection and this method is relatively ideal because it is simple and effective. The high frequency probe of endoscopic ultrasonograph is a reliable method for monitoring implanted pancreatic cancer.