Week 9 Part 2 - Pancreas and Bile Duct FNA

Question 1

Differential Diagnoses for Pancreas FNA

Answer 1

Pancreatitis vs adenocarcinoma
Pseudocyst vs cystic neoplasm
Unusual tumours e.g. endocrine

Question 2

Normal Pancreas FNA

Answer 2

Duct epithelium
Acinar cells

Question 3

Pancreatitis

Answer 3

Common causes are obstruction by a gall stone or alcohol abuse
A clinical diagnosis with serum amylase; Lipase >75u/L
The pancreas may be enlarged or shrunken and nodular
Usually no mass lesion is present but imaging may show a localised abnormality
Chronic pancreatitis is associated with pseudocyst formation
Acute pancreatitis may be peri-tumoral

Question 4

Pseudocyst

Answer 4

Secondary to enzyme release and fat breakdown in chronic pancreatitis
Amylase raised and CEA normal in cyst contents
If infected may form an abscess
DD - cystic neoplasm

Question 5

Pancreatitis Cytology

Answer 5

Necrotic debris - “dirty”
Granular calcific debris, lipid droplets
Inflammatory cells (especially macrophages)
Degenerative and reactive atypia

Question 6

Pancreatic Adenocarcinoma - Clincal

Answer 6

Present with abdominal pain, loss of weight, jaundice
Usually ductal in origin
Usually well to moderately differentiated with a desmoplastic response
5 year survival <5%

Question 7

Pancreatic Adenocarcinoma Cytology - Architecture

Answer 7

High cellularity with large aggregates, clusters, dispersed cells
Monolayered sheets with marked nuclear enlargement and pleomorphism
Gland formation
Crowding, disorganization, disturbed polarity

Question 8

Pancreatic Adenocarcinoma Cytology - Cells

Answer 8

Normal/increased N/C ratio
Cell enlargement
Mitoses
Apoptotic debris in tumour cell sheets

Question 9

Pancreatic Adenocarcinoma Cytology - Nuclei

Answer 9

Enlarged, irregular nuclei with coarse chromatin, hyperchromasia
Large irregular nucleoli
Multinucleation

Question 10

Ancillary Studies to Confirm Pancreatic Adenocarcinoma Malignancy

Answer 10

Ploidy by flow or image analysis
K-ras oncogene mutation using PCR
P53 tumour suppressor gene mutation using immunoperoxidase
S100P, mCEA and MUC1 (Ma695)

Question 11

Mucinous Cystic Tumour

Answer 11

A tumour of middle-aged women found in the tail of the pancreas
Not connected with the duct system
Radiology shows a discrete cystic mass
In the fluid CEA levels are raised and the amylase is normal

Question 12

Mucinous Cystic Tumour Cytology

Answer 12

Variable architectural complexity and cytological atypia
Mucinous columnar cells

Question 13

Endocrine Tumours

Answer 13

Arise from the Islets of Langhans
Generally found in body and tail of pancreas
May be functional or non-functional
May be benign or malignant in behaviour

Question 14

Endocrine Tumours Cytology

Answer 14

Single and loose groups, pseudorosettes
Small round nuclei, minor pleomorphism
Nuclei may be eccentric
Neuroendocrine chromatin i.e. speckled with occasional chromocentres
Poorly defined cytoplasm

Question 15

Endocrine Tumours IHC

Answer 15

Cytokeratins
Broad neuroendocrine markers
- chromogranin and synaptophysin
Specific secretory products
- insulin and gastrin

Question 16

Endocrine Tumours False Negative Results

Answer 16

The needle may not be in the tumour
Necrosis and inflammation may obscure malignant cells
Desmoplastic tumours may not yield cells
Vascular tumours are blood stained with scanty material
Well differentiated or unusual tumours

Question 17

Brushings of Pancreatic or Extra-Hepatic Bile Ducts

Answer 17

Patients present with signs and symptoms of obstruction (i.e. jaundice)
Differential Diagnoses
- benign inflammatory stricture vs adenocarcinoma
Provide a definitive diagnosis of malignancy
Avoid more extensive investigations
Allow palliative therapy

Question 18

Pancreatic Brushings Cytology

Answer 18

Cohesive “honey-comb” sheets of regular
cells
Small rounded or oval nuclei
Columnar row on edge

Question 19

Pancreatic Brushing/Bile Duct Adenocarcinoma - Architecture

Answer 19

Disorganised sheets
Small acinar groups
Loose aggregates
Single pleomorphic cells
Background of necrotic debris

Question 20

Pancreatic Brushing/Bile Duct Adenocarcinoma - Cells

Answer 20

Nuclear crowding and high N:C ratio
Nuclear enlargement and irregular outlines

Question 21

Pancreatic Brushing/Bile Duct Well Differentiated Adenocarcinoma

Answer 21

Cohesive monolayered sheets
Lack the unequivocal nuclear criteria of malignancy
Cell block assessment of architecture may allow a diagnosis of malignancy

Question 22

Pancreatic Brushing/Bile Duct False Positives

Answer 22

History of biliary catheter or stent, sclerosing cholangitis, bile duct stones or pancreatitis
A small amount of material and degenerative changes (bile)
Inflammation - cholangitis/pancreatitis
Absence of “full house” of malignant features

Question 23

Pancreatic Brushing/Bile Duct False Positive Causes - Sampling

Answer 23

Failure to cannulate the duct
Insufficient separate brush samples
Poor instruments - poor cell yield
Fibrosis obscures tumour tissue

Question 24

Pancreatic Brushing/Bile Duct False Positive Causes - Interpretive Errors

Answer 24

Poor slide preparation e.g. air-drying
Small numbers of malignant cells
Well differentiated carcinoma
Special tumour types
Ignoring the smear background