NCIt definition : Prostatic intraepithelial neoplasia characterized by the presence of morphologically
malignant cells lining the acini and ducts. The malignant cells are enlarged, contain
prominent nucleoli, and have increased nuclear/cytoplasmic ratio. The malignant cells
may grow within the ducts and acini in four architectural patterns: flat, tufting,
micropapillary, and cribriform. The presence of high grade prostatic intraepithelial
neoplasia in needle biopsy is a risk factor for the subsequent detection of carcinoma
on repeat biopsy.;