p63 Immunohistochemistry May Skew Breast Cancer Diagnosis

p63 expression is prevalent in high-grade invasive breast carcinomas.

Study included 60 biopsies classified by Nottingham grading system.

80 percent of G3 tumors showed p63 positivity.

G1 tumors were negative for p63 in invasive components.

Limited and focal p63 staining occurs in G3 tumors across subtypes.

Importance of distinguishing between p63 positivity and residual myoepithelial cells.

Suggests implications for diagnostic pathology.