Psammoma bodies

A psammoma body is a round collection of calcium, seen microscopically. The term is derived from the Greek word ψάμμος (psámmos), meaning "sand".

Psammoma bodies are associated with the (nipple-like) histomorphology and are thought to arise from (1) the infarction and calcification of papillae tips and (2) calcification of intralymphatic tumor thrombi.

Psammoma bodies are commonly seen in certain tumors such as:

Psammoma bodies may be seen in:

Psammoma bodies usually have a laminar appearance, are circular, acellular and basophilic.

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