Radiation Oncology/Pancreas/Squamous Cell


  • Squamous cells not normally present in pancreas, so four theories have been proposed:
    • Metaplasia of pancreatic ductal epithelium present during inflammation (eg during pancreatitis)
    • Pluripotent progenitor cell capable of differentiating to adeno or squamous undergoes malignant transformation
    • Pre-existing adenocarcinoma undergoes transformation to squamous cell
    • Aberrant squamous cell undergoes malignant transformation
  • Reported incidence between 0.005% (pure squamous) and 2% (adenosquamous) tumors of pancreatic tumors
  • 61 cases reported in English literature (PMID 16208119)
    • Mean age 62 years
    • Presenting symptoms: abdominal or back pain, weight loss, anorexia
    • Average tumor size 7.8 cm
    • Equal distribution between head, body and tail
    • Median survival: resected 7 months, non-resectable 3 months
  • Given its rarity, it is important to exclude metastatic disease from elsewhere
  • Enhances on triphasic contrast CT
  • Consider gemcitabine-based chemotherapy

Adenosquamous carcinoma

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  • PMID 10367867, 1999 — "Adenosquamous carcinoma of the pancreas." (Madura JA. Arch Surg. 1999 Jun;134(6):599-603.)
    • Retrospective review of 6 patients
    • Approximately 4% of all pancreatic neoplasms (only 134 cases reported at the time of publication - 1999)
    • Discussion states positive Ca 19-9, ST 439, keratin staining
    • Survival = 5.4 +/- 4 months