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 (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 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