The Use Of An Endoscopic Ultrasound-Guided Through-The-Needle-Forceps Biopsy In The Evaluation Of Pancreatic Cystic Lesions: A Multicenter Retrospective Study

Pancreatic cystic lesions (PCLs) are diagnosed with increasing frequency. Yet, the accurate diagnosis and classification of PCLs remains a challenge. The endoscopic ultrasound (EUS)-guided through-the-needle biopsy forceps (TTNB) is a novel tissue sampling device for PCLs. The primary aim was to evaluate the safety and feasibility of EUS-TTNB of PCLs. The secondary aim was to assess the potential incremental diagnostic yield of TTNB of mucinous cysts. Retrospective analysis of consecutive patients undergoing EUS fine-needle aspiration (FNA) and TTNB for PCLs in 3 tertiary care centers between January 2014 to June 2017. Cyst fluid CEA was used to initially categorize cysts as nonmucinous (CEA <192ng/mL) or mucinous (CEA ≥192ng/mL). Adequate cellular specimen for cytology or histology was defined as that being sufficient to characterize the lesion. A cyst was determined to be mucinous on cytology or histology by the presence of mucinous pancreatic cystic epithelium. Final diagnosis was confirmed by pathology of surgical resected specimen when available. EUS-TTNB (median of 1 pass) was successfully performed in all 52 (100%) consecutive patients (mean age 66.1±12.7 years; 56% women) with PCLs during the study period. Mean PCL size was 30.7 mm, range 11.6-110 mm. An adequate cellular specimen was more commonly obtained with EUS-TTNB (88.2%) compared to EUS-FNA (51.9%) (p<0.001). For cysts with insufficient amount of fluid for CEA (n=19) or CEA<192 ng/mL (n=22), the cumulative incremental diagnostic yield of a mucinous cyst was significantly higher with EUS-TTNB (51.2%) compared to EUS-FNA (17%) (p=0.002). Nine (17%) patients underwent surgical resection. Surgical pathology was positive for a mucinous cyst (intrapapillary mucinous neoplasm or mucinous cystic neoplasm) in 7 cases, of which EUS-TTNB and EUS-FNA were diagnostic in 6 (85.7%) and 3 (42.9%) respectively. In all, there were two cases of self-limited intracystic bleeding (3.8%) that did not require additional interventions. There was one case (1.9%) of mild acute pancreatitis reported 48 hours after the procedure. EUS-TTNB is a safe and effective technique for the evaluation of PCLs. EUS-TTNB is a viable adjunctive tissue acquisition method that may help increase the diagnostic yield of pancreatic mucinous cysts during EUS.View Large Image Figure ViewerDownload Hi-res image Download (PPT)