Corpora amylacea

Corpora amylacea are small hyaline masses of unknown significance found in the prostate gland, neuroglia, and pulmonary alveoli. They are derived from degenerate cells or thickened secretions and occur more frequently with advancing age. While their significance is unknown, they can be used to identify these organs microscopically.

In the brain, corpora amylacea are contained in foot processes of astrocytes and are usually present in sub-pial location and around blood vessels. In comparison to prostatic corpora amylacea, these are only faintly laminar and less eosinophilic. The major constituent has been shown to be polyglycosan. These bodies have no known pathologic correlation and can be confused with fungal yeast forms such as cryptococcus.

In the prostate, where they are also known as prostatic concretions, they usually appear in benign glands; however, their presence cannot be used to exclude cancer.

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