Ductal Adenocarcinoma of the Pancreas
Definition
- Carcinoma of the pancreas exhibiting ductal differentiation
Alternate/Historical Names
- Pancreatic adenocarcinoma
- Pancreatic carcinoma
Diagnostic Criteria
- Irregular glands
- Usually at least the size of medium sized ducts
- Small gland carcinomas can be seen
- Partial / incomplete glands
- Single infiltrating cells may be seen
- Usually at least the size of medium sized ducts
- Haphazard, disorganized invasive pattern
- Loss of lobular grouping and ductal branching pattern
- Presence of ducts adjacent to muscular vessels
- Perineural invasion
- Has been reported rarely in chronic pancreatitis
- Bare ducts in fat
- Only thin rim of fibromuscular tissue
- 50% sensitive on resection specimens, 2% on biopsies
- Very specific (reported 100%)
- May invade into pre-existing ducts
- Variable nuclear pleomorphism
- Bland cases rely on architectural features for diagnosis
- Nuclear variability with at least 4:1 nuclear size ratios is virtually diagnostic
- Nucleoli >1/4 the diameter of the nucleus are strongly supportive of carcinoma
- Frequent desmoplastic stromal response
- Occasional patterns (no clinical significance)
- Foamy gland
- Columnar cells with abundant apical microvesicular cytoplasm
- Mucin negative cytoplasm but apical cytoplasm may show some staining
- Apical cytoplasmic condensation reminiscent of a brush border
- Basally located hyperchromatic small cytologically bland nuclei
- Recognize based on invasive pattern
- Columnar cells with abundant apical microvesicular cytoplasm
- Clear cell
- Negative for cytoplasmic glycogen and mucin
- Reminiscent of renal cell carcinoma
- May form solid areas
- Mucin scant to negative in most cases
- A frequent focal pattern in ordinary adenocarcinomas
- Should be at least 75% clear to be designated clear cell variant
- One study (Kim) suggests a worse prognosis
- Cystic papillary
(Kelly)
- Cysts 0.5-1.1 cm
- Lined by tall mucinous cells
- Complex papillae
- Usually mixed with conventional ductal adenocarcinoma
- May predominate
- Elastin stain negative (distinguishes from IPMN)
- Foamy gland
- The following are considered separately as they may have different behavior or clinically distinct features:
- Adenosquamous carcinoma
- Colloid carcinoma
- Hepatoid carcinoma
- Medullary carcinoma
- Micropapillary carcinoma
- Signet ring cell carcinoma
- Undifferentiated carcinoma
- Undifferentiated carcinoma with osteoclast-like giant cells
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting / last update: 1/4/08, 6/17/12
