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Search: Organ site Search: Tumor / Syndrome
WHO Classification of Tumours
Diffuse astrocytoma
Tumours of the central nervous system


Because of their infiltrative nature, these tumours usually show blurring of the gross anatomical boundaries. There is enlargement and distortion, but not destruction, of the invaded anatomical structures, e.g. cortex and compact myelinated pathways. Local mass lesions may be present in either grey or yellow-white matter, but they have indistinct boundaries, and changes such as smaller or larger cysts, granular areas and zones of firmness or softening may be seen. Cystic change most commonly appears as a focal spongy area, with multiple cysts of varying size. Extensive microcyst formation may cause a gelatinous appearance. Occasionally, a single large cyst filled with clear fluid may be present. Tumours with prominent gemistocytes sometimes have single large smooth-walled cysts. Focal calcification may also be present, and a more diffuse grittiness may be observed. Extension into contralateral structures, particularly in the frontal lobes, is often observed.

Frontal astrocytoma
Frontal astrocytoma