56-year-old female suffered recently from epigastric pain. In addition, she developed jaundice. A CT-scan revealed a tumor in the head of the pancreas. A Whipple operation was performed.
- A section through the head of the pancreas and the duodenum is shown.
- An ill-defined tumor is observed that infiltrates and destroys the surrounding tissue. The tumor infiltrates the duodenal muscularis propria. Invasion of lymphatic vessels and nerves is present.
- The tumor consists of irregular glands embedded in a desmoplastic stroma. The lobular architecture of normal pancreatic exocrine tissue is missing.
- Glands are lined by columnar eosinophilic cells exhibiting distinct nuclear atypia. Nuclei are large, round to ovoid and feature distinct nucleoli. Mitotic figures are rare.
- Many glands contain PAS positive mucin (neutral glycosaminoglycanes and carbon hydrates).
- The peripheral pancreatic tissue is inconspicuous, with regular exocrine glands and islets.
At times, the diagnosis of a well differentiated ductal adenocarcinoma may be extremely difficult (differential diagnosis chronic pancreatitis). Neoplastic glands may be well formed and thus, the architecture may not be suggestive of malignancy. However, cytologic atypias are marked and the normal lobular architecture of exocrine pancreatic tissue is missing. Compare the neoplastic glands with the glands of the intact pancreatic tissue!
Ductal adenocarcinomas and its variants are by far the most frequent tumors of the pancreas, accounting for around 85% of all pancreatic malignancies.