Partial atrophy on prostate needle biopsy cores: a morphologic and immunohistochemical study

Area of Science:

• Uropathology
• Oncologic Pathology
• Diagnostic Pathology

Background:

• Partial atrophy is a common benign finding in prostate needle biopsies.
• It can be mistaken for prostate adenocarcinoma by pathologists.
• Immunohistochemical stains are often used to differentiate benign from malignant conditions.

Purpose of the Study:

• To analyze the morphologic and immunohistochemical features of partial atrophy.
• To determine the frequency of partial atrophy mimicking prostate cancer.
• To provide guidance for accurate diagnosis of partial atrophy.

Main Methods:

• Review of 278 prostate needle core biopsy cases diagnosed with partial atrophy.
• Morphologic analysis of hematoxylin and eosin-stained sections.
• Immunohistochemical analysis using a triple cocktail stain (p63, high molecular weight cytokeratin, AMACR) and basal cell markers.

Main Results:

• Partial atrophy showed features that mimicked adenocarcinoma, including enlarged nuclei and prominent nucleoli.
• Immunohistochemistry revealed various patterns, with some cases showing cancer-like staining for basal cells and AMACR.
• A significant percentage of partial atrophy cases (24.2%) exhibited a cancer pattern for both basal cells and AMACR.

Conclusions:

• Partial atrophy is a significant benign mimicker of prostate adenocarcinoma on needle biopsy.
• Both routine morphology and immunohistochemical profiles can resemble cancer.
• Accurate recognition of partial atrophy's classic morphology on H&E stains is essential to prevent misdiagnosis.