Squamous/Adenosquamous Carcinoma, Pancreas
Mari Mino-Kenudson, MD
Key Facts
Terminology
Pure squamous or mixed glandular and squamous carcinoma of pancreas
Clinical Issues
Adenosquamous carcinoma accounts for 3-4% of exocrine pancreas malignancies
Pure squamous cell carcinoma is vanishingly rare
Extremely poor survival
Microscopic Pathology
Squamous cell carcinoma exhibits only squamous component
Adenosquamous carcinoma has malignant glandular and squamous components
Glandular component may contain conventional ductal-type, clear cell, or signet ring cell components
 A primary adenosquamous cell carcinoma in the tail of the pancreas shows a relatively well-demarcated tanwhite to yellow solid mass with a cystic component. |
 Adenosquamous cell carcinoma of the pancreas demonstrates islands of malignant squamous cells with keratinization  adjacent to PanIN-3 involving an interlobular duct  . |
TERMINOLOGY
Definitions
Uncommon variant of pancreatic cancer with both glandular and squamous differentiation
Pure squamous cell carcinoma of pancreas is vanishingly rare
ETIOLOGY/PATHOGENESIS
Neoplastic
A few hypotheses attempt to explain origin of squamous component
Squamous metaplasia of pancreatic duct epithelium
Both components derive from common progenitor
CLINICAL ISSUES
Epidemiology
Incidence
Adenosquamous carcinoma accounts for 3-4% of malignancies of exocrine pancreas
Pure squamous cell carcinoma reportedly accounts for up to 0.7% of pancreatic carcinoma
Age
