Bojan Kovacevic

Endoscopic ultrasound guided needle-based confocal laser endomicroscopy in solid pancreatic masses – a prospective validation study

Background and study aims  Endoscopic ultrasound fine-needle aspiration (EUS-FNA) is a keystone in diagnosing and staging of pancreatic masses. Recently, a microfiber that can pass through a 19-gauge needle has been introduced for confocal laser endomicroscopy (nCLE). The aims of this study were to evaluate the diagnostic value and the reproducibility of nCLE criteria for solid malignant lesions. Patients and methods  This prospective dual-center study included patients with pancreatic masses suspicious of malignancy referred for EUS-FNA. Endomicroscopic imaging was performed under EUS-guidance until organ-specific structures were obtained. Afterwards, standard cytology was obtained and patients were followed for up to 12 months. All nCLE parameters included in former studies were correlated with the final diagnosis (dark lobular structures/normal acinar cells, dark cell aggregates > 40 µm, dilated irregular vessels with fluorescein leakage, fine white fibrous bands, small black cell movements, pseudoglandular structures). Finally, three CLE novices and three CLE experts assessed the unedited movies from all patients. Results  Twenty-eight patients were enrolled in the study. A final diagnosis was obtained in 24 patients (86 %). One patient (3 %) died before a diagnosis was obtained, while 3 were lost to follow-up (11 %). In 18/24 patients (74 %) the diagnosis was malignant. The mean sensitivity, specificity, and accuracy for the nCLE parameters ranged from 19 – 93 %, 0 – 56 %, 26 – 69 %, respectively. The inter-observer values ranged from κ = 0.20 – 0.41 for novices and κ = –0.02 – 0.38 for experts. Conclusions  The diagnostic value of nCLE in solid pancreatic masses is questionable and the inter-observer agreement for both novices and CLE experts appears limited.

Intraductal tubulopapillary neoplasm of the pancreas diagnosed by endoscopic ultrasonography-guided fine needle aspiration

A 68-year-old man with chronic alcoholrelated pancreatitis and chronic nephropathy requiring dialysis was admitted to the hospital because of a 3-day history of upper abdominal pain. Laboratory tests revealed slightly elevated C-reactive protein with normal amylase and liver function test results. Computed tomography scan of the abdomen showed pancreatic calcifications and a cystic lesion in the head/neck of the pancreas. Subsequent endoscopic ultrasound (EUS) showed a multicystic lesion (▶Fig. 1) with a dilated main pancreatic duct and a suspected solid lesion (▶Fig. 2). EUS-guided fine needle aspiration (FNA) of the suspected solid lesion in the main pancreatic duct was performed. Histopathology showed tubulopapillary structures with cylindrical cells and low grade dysplasia (▶Fig. 3, ▶Video1). There were no signs of mucin on periodic acid–Schiff and Alcian blue staining. On immunohistochemistry, the lesion was positive for CK7, CDX2 and MUC-1, and there was focal MUC6 reaction but only very few MUC5AC positive cells. The findings were consistent with an intraductal tubulopapillary neoplasm (ITPN). The patient was considered unfit for surgical treatment, and 6 months following the diagnosis he is alive without signs of disseminated disease. ITPN is relatively rare, accounting for approximately 3% of all resected pancreatic intraductal neoplasms [1]. It may be radiologically indistinguishable from intraductal papillary mucinous neoplasm (IPMN). The diagnosis is made histologically, as ITPNs exhibit a tubular/cribriform growth with only minimal luminal/ intracellular mucin, whereas IPMNs show a papillary growth pattern [2]. On immunohistochemistry, IPMNs, but not ITPNs, are MUC5AC positive [3]. Although treatment of both tumors is similar, the prognosis of patients with ITPN is typically better than that for IPMN. This might be a relevant consideration when deciding the follow-up of patients, particularly those who are poor surgical candidates. To our knowledge, ours is one of the very few published cases on the appearance of ITPN on EUS and on the utility of EUS-FNA in the differential diagnosis. Endoscopy_UCTN_Code_CCL_1AF_2AZ_3AB

Diagnosis of intraductal papillary mucinous neoplasm using endoscopic ultrasound guided microbiopsies: A case report

Pancreatic cysts are increasingly diagnosed due to expanding use of cross-sectional imaging, but current diagnostic modalities have limited diagnostic accuracy. Recently, a novel through-the-needle microbiopsy forceps has become available, offering the possibility of obtaining cyst-wall biopsies. We present a case of 41-year-old male with chronic pancreatitis and a 2-cm pancreatic cyst, initially considered a pseudocyst. Subsequently, endoscopic ultrasound guided microbiopsies were successfully obtained, which surprisingly revealed an intraductal papillary mucinous neoplasm of mixed subtype with low grade dysplasia. In conclusion, obtaining biopsies from the wall of the pancreatic cystic lesions with this novel instrument is feasible and, as demonstrated in this case, can possibly alter the clinical outcome. Microbiopsies offered enough cellular material, allowing supplemental gene mutation analysis, which combined with other modalities could lead to a more individual approach when treating pancreatic cysts. However, prospective studies are warranted before routine clinical implementation.

Initial experience with EUS-guided microbiopsy forceps in diagnosing pancreatic cystic lesions: A multicenter feasibility study (with video)

Background and Objectives: Cystic lesions of the pancreas represent a diagnostic dilemma. Recently, a through-the-needle microbiopsy forceps has become available, enabling procurement of EUS-guided histological specimens from the pancreatic cyst wall. The aim of this study was to evaluate the use of this novel instrument in a multicenter clinical setting. Patients and Methods: Patients referred for EUS evaluation of pancreatic cysts and attempted EUS-guided microbiopsy was included retrospectively from six international tertiary centers. Patients demographics, EUS findings, technical and clinical success, and histopathological results were recorded. Results: A total of 28 patients were identified. We report a technical success rate of 85.7% (n = 24). Biopsies were generally of good quality and contributed to the diagnosis in 20 patients (clinical success of 71.4%). Three adverse events were recorded (10.7%). Conclusions: The use of the microbiopsy forceps is feasible with acceptable rates of technical and clinical success. Prospective studies are warranted to determine the diagnostic potential compared to the other modalities. However, the results from this preliminary study are promising.

Endoscopic Ultrasonography-Guided Gastrojejunostomies With Lumen-Apposing Metal Stents

Figure 1. Computed tomography scan of the newly formed gastrojejunostomy, showing a well-placed LAMS. Gastric outlet obstruction usually is caused by upper gastrointestinal malignancies, such as carcinomas located in the pancreas, stomach, gallbladder, or duodenum, but it also is seen in several benign diseases (eg, pancreatic pseudocysts or benign strictures). Current treatment of gastric outlet obstruction involves either creation of a surgical anastomosis to bypass the obstruction, or by placing a self-expandable metal stent (SEMS) through the obstruction. The search for minimally invasive alternatives to surgery has led to the development of a bi-flanged lumen-apposing metal stent (LAMS), suitable for endoscopic anastomosis. As the stent is released, the distal set of flanges attaches to the jejunum and approximates it to the stomach where the second set is released, creating a short fistula (Figure 1). Although this currently is an experimental procedure, it emerges as a minimally invasive alternative to conventional surgery and SEMS. The aim of this review therefore is to extract and present an overview of the current evidence on the topic.