High Grade Prostatic Intraepithelial Neoplasia

**Semantic type:** Neoplastic Process

**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.

**Synonyms:** - HGPIN - High-Grade Intraepithelial Neoplasia of Prostate - High-Grade Intraepithelial Neoplasia of the Prostate - High-Grade PIN - High-Grade Prostatic Intraepithelial Neoplasia - High-grade Prostatic Intraepithelial Neoplasia (PIN) - Prostatic intraepithelial neoplasia (high grade)