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Crystalloid structures in retroperitoneal paragangliomas: a light and electron microscopic study.
K Kyriacou1, F H Shipkey, R Loewen
1Department of Pathology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
Ultrastructural Pathology
|January 1, 1991
Summary
Retroperitoneal paragangliomas contain unique crystalloids within tumor cells. These crystalloids, distinct from catecholamine granules, selectively contain chromium, offering new insights into tumor cell biology.
Area of Science:
- Endocrinology
- Oncology
- Pathology
Background:
- Retroperitoneal paragangliomas are rare neuroendocrine tumors arising from chromaffin cells.
- These tumors can secrete catecholamines, leading to significant clinical manifestations.
- Understanding the ultrastructural and biochemical characteristics of these tumors is crucial for diagnosis and management.
Purpose of the Study:
- To investigate the histological and ultrastructural features of clinically functional retroperitoneal paragangliomas.
- To characterize the nature of prominent cytoplasmic crystalloids observed in these tumors.
- To determine the elemental composition of catecholamine granules and crystalloids using X-ray microanalysis.
Main Methods:
- Light and electron microscopy were employed to examine tumor samples.
- Histochemical stains (periodic acid-Schiff, Giemsa, phloxine-tartrazine, azan) were used.
- Ultrastructural analysis focused on crystalloid morphology and membrane-bound characteristics.
- X-ray microanalysis was performed to identify elemental composition.
Main Results:
- Tumors displayed a characteristic Zellballen pattern histologically.
- Ultrastructurally, tumor cells contained catecholamine granules and prominent cytoplasmic crystalloids.
- Crystalloids were eosinophilic, stained with various histochemical stains, and appeared as slender, osmiophilic needles with 9 nm periodicity.
- Crystalloids were negative for catecholamine fluorescence but, along with catecholamine granules, showed selective chromium presence via X-ray microanalysis.
Conclusions:
- Clinically functional retroperitoneal paragangliomas possess distinctive cytoplasmic crystalloids.
- These crystalloids are biochemically distinct from catecholamine granules but share chromium content.
- The presence of chromium in both structures warrants further investigation into their role in paraganglioma pathophysiology.