P53

P53
Immunostain in short
p53 staining in an anaplastic astrocytoma.
Use	cancer versus benign, prognostication
Positive	nuclear staining (>60% or completely negative - see interpretation)

p53 marks a tumour suppressor protein commonly implicated in cancer and a common immunostain.

Interpretation

• p53 may be one of the most misinterpreted stains.
  • TP53 mutations are associated with >60% staining and no staining (0% of cell labelled).
• Reliable interpretation of p53 may require co-assesment of other markers.
  • In neuropathology strong p53 expression in combination with loss of ATRX nuclear expression may allow one to skip the otherwise needed LOH 1p/19q testing in diffuse gliomas.

See also

• Molecular pathology.
• Li-Fraumeni syndrome.