Figure 1.

Acinar cell clusters or lobules with cytoplasmic p63 expression. Sections from paraffin embedded tissues of PABC were immunostained for p63 (brown or red). Circles identify normal appearing lobules in which all acinar cells show cytoplasmic p63 expression. Thin and thick arrows identify cells with nuclear and cytoplasmic p63 expression, respectively. Asterisks identify invasive tissue components. In tissues without or distant from malignant lesions, both cytoplasmic and nuclear p63 expression cells are seen (a-d), whereas in tissues harbored or adjacent to malignant lesions (e-h), all or nearly all cells within a given lobule uniformly show high levels of cytoplasmic p63 expression. a, c, e, and g: 100X; b, d, f, and h: a higher (300X) magnification of a, c, e, and g, respectively.