Phaeochromocytoma Flashcards
What is a pheochromocytoma and where does it originate?
Pheochromocytoma is a tumor that arises from the adrenal medulla, specifically from chromaffin cells.
What is the term for similar tumors that arise from extra-adrenal paraganglia?
These are called paragangliomas.
What histological feature is characteristic of pheochromocytomas and consists of nests of tumor cells separated by rich vasculature?
This feature is known as zellballen architecture.
What is the cytological appearance of pheochromocytoma cells under the microscope?
The cells are polygonal with amphophilic (purplish) cytoplasm, and round to oval nuclei showing salt and pepper chromatin.
What are the key histological indicators of potentially aggressive behavior in pheochromocytomas?
Indicators include tumor necrosis, increased mitotic activity, marked pleomorphism, and the only definitive sign of malignancy is the presence of metastases.
