Makindo Medical Notes

Overview of Psammoma Bodies

Psammoma bodies are round, calcified structures that are commonly found in certain types of tumours and other pathological conditions. They are composed of concentric layers of calcified material and are often seen in association with certain types of cancer.

Characteristics

• Structure:
  • Concentric, lamellated, calcified structures.
  • Typically round or oval in shape.
  • Vary in size but usually measure less than 100 micrometers in diameter.
• Composition:
  • Composed primarily of calcium and sometimes contain other minerals.
  • Formed by the progressive deposition of calcium around a central nidus or core.

Pathological Significance

• Commonly Associated Tumours:
  • Papillary thyroid carcinoma
  • Serous papillary ovarian carcinoma
  • Meningioma
  • Mesothelioma
  • Papillary renal cell carcinoma
• Other Conditions:
  • Endometrial carcinoma
  • Some benign conditions, such as endosalpingiosis

Diagnostic Importance

• Histopathology:
  • Psammoma bodies can be identified using routine histological staining techniques.
  • Appear as basophilic, concentric lamellated structures under the microscope.
• Clinical Relevance:
  • The presence of psammoma bodies can be a helpful diagnostic marker for certain types of tumours.
  • May indicate the presence of an underlying malignancy, especially in the context of thyroid, ovarian, and meningeal tumours.

Mechanism of Formation

• Cellular Mechanisms:
  • Believed to form from the necrosis of tumour cells, which provides a nidus for calcium deposition.
  • May also form from the calcification of degenerating papillary structures within tumours.
• Role of Inflammation:
  • Chronic inflammation may contribute to the formation of psammoma bodies by promoting calcification processes.

Examples in Specific Tumours

• Papillary Thyroid Carcinoma:
  • Psammoma bodies are frequently found in papillary thyroid carcinoma and are considered a characteristic feature of this type of cancer.
• Serous Papillary Ovarian Carcinoma:
  • Psammoma bodies are commonly seen in serous papillary ovarian carcinoma and can aid in the diagnosis of this tumour.
• Meningioma:
  • Meningiomas often contain psammoma bodies, which can help distinguish them from other types of central nervous system tumours.

Summary

Psammoma bodies are calcified structures that are commonly found in certain types of tumours and pathological conditions. They are characterized by their concentric, lamellated structure and are composed primarily of calcium. Psammoma bodies are diagnostically significant, as their presence can indicate certain types of malignancies, such as papillary thyroid carcinoma, serous papillary ovarian carcinoma, and meningioma. Understanding the formation and significance of psammoma bodies can aid in the diagnosis and treatment of these conditions.