Related Experiment Video
Updated: Jan 22, 2026
Preparation and Using Phantom Lesions to Practice Fine Needle Aspiration Biopsies
Published on: September 29, 2009
Interobserver agreement among expert pathologists on through-the-needle microforceps biopsy samples for evaluation of
Alberto Larghi1, Erminia Manfrin2, Carlo Fabbri3
1Digestive Endoscopy Unit, Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy.
Background And Aims:
The recent development of microforceps for EUS through-the-needle biopsy (TTNB) sampling of the wall of pancreatic cystic lesions (PCLs) allows the collection of histologic specimens never handled and evaluated before by pathologists. We aimed to estimate the interobserver agreement among pathologists in evaluating such samples.
Methods:
TTNB specimen slides from 40 PCLs with worrisome features were retrieved and independently evaluated for specimen adequacy, presence of lining epithelium, grade of epithelial dysplasia, presence of ovarian type stroma, and specific diagnosis by 6 expert pathologists from 6 different tertiary care centers. The Gwet's AC1 was used to assess interobserver agreement.
Results:
An almost perfect agreement was observed for specimen adequacy (AC1, .82; 95% confidence interval [CI], .79-.98), presence of lesional epithelium (AC1, .90; 95% CI, .86-.92), epithelial dysplasia (AC1, .97; 95% CI, .95-.99), and ovarian-like stroma (AC1, .90; 95% CI, .86-.93). When considering all diagnoses separately, a moderate to substantial agreement was observed (AC1, .62; 95% CI, .57-.67), similarly to mucinous cysts versus serous adenoma versus other diagnoses (AC1, .65; 95% CI, .59-.70) and for mucinous cysts versus all other diagnoses (AC1,.74; 95% CI, .68-.84). The agreement for diagnosis of mucinous cystic neoplasm versus intraductal mucinous papillary neoplasm was almost perfect (AC1, .88; 95% CI, .81-.95).
Conclusions:
Interobserver agreement between expert pathologists in the evaluation of TTNB samples from PCLs with worrisome features was close to perfection for all evaluated parameters, except definitive diagnosis. When mucinous cystic lesions were compared versus all other diagnoses, the agreement became substantial, thus indicating that TTNB specimens can provide important information for PCL management decisions.
Insights
New microforceps for endoscopic ultrasound-guided through-the-needle biopsy (EUS-TTNB) of pancreatic cystic lesions (PCLs) allow histologic sampling. Pathologist agreement is high for specimen adequacy and features, aiding PCL management.
Area of Science:
- Gastroenterology
- Pathology
- Oncology
Background:
- Microforceps enable endoscopic ultrasound-guided through-the-needle biopsy (EUS-TTNB) of pancreatic cystic lesions (PCLs).
- Histologic specimens from PCLs can now be evaluated by pathologists.
- This study assesses interobserver agreement in evaluating EUS-TTNB samples.
Purpose of the Study:
- To estimate interobserver agreement among pathologists evaluating EUS-TTNB samples from PCLs.
- To determine the reliability of histologic assessment of PCLs using EUS-TTNB.
- To inform PCL management decisions based on EUS-TTNB specimen evaluation.
Main Methods:
- Forty PCLs with worrisome features were sampled using EUS-TTNB.
- Six expert pathologists independently evaluated specimen adequacy, lining epithelium, dysplasia, ovarian-type stroma, and specific diagnoses.
- Gwet's AC1 statistic was used to assess interobserver agreement.
Main Results:
- Almost perfect agreement was found for specimen adequacy (AC1=.82), lesional epithelium (AC1=.90), dysplasia (AC1=.97), and ovarian-like stroma (AC1=.90).
- Moderate to substantial agreement was observed for overall diagnoses (AC1=.62) and specific comparisons (e.g., mucinous vs. serous, AC1=.65).
- Agreement was almost perfect for distinguishing mucinous cystic neoplasm from intraductal papillary mucinous neoplasm (AC1=.88).
Conclusions:
- Interobserver agreement for evaluating EUS-TTNB samples from PCLs is high for most parameters, except definitive diagnosis.
- Substantial agreement for classifying mucinous cystic lesions versus other diagnoses indicates the clinical utility of EUS-TTNB.
- EUS-TTNB specimens provide valuable information for managing PCLs.
Related Concept Videos
01:23Cystic Fibrosis: Pathogenesis
CF is primarily caused by a genetic mutation in a chromosome 7 gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The most common gene mutation leading to CF is the ΔF508 mutation,...
01:24Cystic Fibrosis: Management
Sinus disease and chronic...
01:26Pancreatic Juice and Secretion
When acidic chyme from the stomach enters the duodenum, it triggers the release of secretin, a hormone that prompts pancreatic juice secretion. After a fatty meal, cholecystokinin, another hormone, stimulates gallbladder contraction and enhances enzyme-rich...
01:27Acute Pancreatitis I: Introduction
Acute pancreatitis is characterized by rapid inflammation of the pancreas, often caused by factors like gallstone blockage or excessive alcohol consumption. Chronic pancreatitis, on the other hand, is a slow, progressive inflammation that may result from long-term alcohol abuse, obstructions in the pancreatic duct, or genetic factors.
The causes of acute pancreatitis include:
01:24Chronic Pancreatitis I: Introduction
Pancreatitis is the inflammation of the pancreas, which occurs when the immune system becomes active and causes swelling, pain, and disruptions in organ function. Pancreatitis can manifest as either an acute or chronic condition.
Acute pancreatitis arises suddenly and lasts for a brief duration, while chronic pancreatitis is a long-term affliction...
01:18Sampling Methods: Sample Types
Solid samples include a variety of substances, such as sediments from water bodies, soil, metals, and biological tissues. Two standard methods for extracting sediments from water bodies are grab sampling and piston coring. Grab sampling involves using a device to collect a discrete sediment sample from the bottom of a water body with minimal disturbance. Grab samples do not always represent the entire area due to...