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Published on: May 11, 2015
Insulinoma with fibrillar inclusions and acinar cell elements
1The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Ultrastructural Pathology
|January 11, 2002
Summary
This study reports a rare pancreatic insulinoma with both endocrine and exocrine cell features. The findings suggest a common origin for pancreatic endocrine and exocrine tissues.
Area of Science:
- Endocrinology
- Surgical Pathology
- Developmental Biology
Background:
- Islet cell tumors are neoplasms of pancreatic endocrine cells.
- Tumors with mixed endocrine and exocrine components are exceptionally rare.
- Insulinomas are the most common type of functioning pancreatic neuroendocrine tumor.
Observation:
- A 33-year-old woman presented with an insulinoma.
- Histopathological examination revealed a tumor with endocrine cells and a population of acinar cells.
- Rare amphicrine cells with both endocrine and exocrine differentiation were identified.
Findings:
- The pancreatic tumor exhibited mixed endocrine and exocrine cell morphology.
- Unusual intracytoplasmic filamentous inclusions were observed in the tumor cells.
- The presence of amphicrine cells supports a shared embryologic origin for pancreatic cell types.
Implications:
- This case provides evidence for a common progenitor cell for pancreatic endocrine and exocrine tissues.
- Understanding tumor heterogeneity can inform diagnostic and therapeutic strategies.
- Further research into pancreatic tumorigenesis is warranted.
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