Detection of very well differentiated adenocarcinoma of pancreas and bile duct epithelium

TOM MENGMarch 24, 2008

Cytology of biliary tract, including the ampulla of Vater, common bile duct, and pancreatic duct is becoming increasingly important for variety of reasons. Cytological examination cannot only aid in the diagnosis but can spare the patient unnecessary surgery (2,P357).

However, adenocarcinoma of pancreas and bile duct epithelium may be very well differentiated. Sometimes confusion of diagnosis may occur, so distinguishing them from benign has cytological significance.

Features will be presented to help at least diagnose suspicious for adenocarcinoma.

Bile duct

Normal bile ductal cells:

Cohesive, monolayer sheet of medium-sized columnar or cuboidal cells

Form regular, honeycombing or palisading arrangement

Nuclei are round to oval with smooth nuclear membranes

Fine, evenly distributed chromatin

Normal bile duct cells

Normal bile duct cells

W.D. Adenocarcinoma of bile duct:

May be extremely well differentiated, so any change from normal may be suspicious such as:

Loss of polarity OverlappingCluster or 3-D ballIncreased N/C ratio Slight nuclear enlargementSlight nuclear membrane irregularitiesSlight hyperchromasiaProminent nucleoli

AdenocarcinomaOf bile duct

Benign

Malignant

AdenocarcinomaOf bile duct

AdenocarcinomaOf bile duct

Pancreas

Normal pancreatic ductal cells

The cells of the pancreatic duct and bile duct are cytologically similar(2 P358):

Cuboidal to columnar cells, rare to see ciliaMonolayer groups usually honeycombing or picket fencing

Round or oval basally located nuclei Evenly distributed, finely granular chromatinSmooth nuclear membranes

Normal pancreaticDuctal cells

Pancreatic Adenocarcinoma

May be extremely well differentiated, so any change from normal may be suspicious such as:

Overlapping nucleiClusters or 3-D ballLoss of polarityIncreased N/C ratioSlight nuclear enlargementSlight hyperchromasia

Slight nuclear membrane irregularitiesProminent nucleoli

May see cytoplasmic vacuolization and mitoses

Adenocarcinoma of pancreas

Adenocarcinoma of pancreas

Adenocarcinoma of pancreas

Adenocarcinoma of pancreas

ProstateAdenocarcinoma of three sites may be very well

differentiated: pancreas, bile duct, and prostate. Diagnosis of prostatic FNA is similar to pancreas and bile duct. Helpful in prostate cytology is the presence of branching and bridging structures = very suspicious for adenocarcinoma.

However, FNA of prostate for cytology is uncommon today due to use of biopty gun and core of tissue for better diagnosis.

References:

1 The Manual of Cytotechnology, Catherine M. Keebler2 The art & Science of Cytopathology, Richard M Demay3 Manual and Atlas of Fine Needle Aspiration Cytology, Svante R. Orell

Normal prostatic ductal cells

Adenocarcinoma of Prostate