Table I.

Prostate Histology Grading System.

Histological classification	Prominent nuclei	Atypical cells		Invasion	Disrupted Gland Profile
		Intact Stroma	Large Foci
Typical
Atypical Hyperplasia	×	×
Mouse Prostate Intraepithelial	×		×
Neoplasia (mPIN)
mPIN with invasion	×		×	×
Adenocarcinoma	×		×		×

The histological classification of prostate tissue was based on examining prominent nuclei, atypical cells, invasion and disrupted glandular profiles. Prominent nuclei are defined as nuclei that stand out in the cell, contain mostly pronounced nucleoli, and may contain mitotic bodies. Atypical cells refer to the morphology of the cells which are more columnar and start to stack upon one another as compared to typical cells which are rounder and are arranged in a single layer. Invasion refers to a spot where the atypical foci infiltrate into the surrounding basal membrane. Disrupted gland profile refers to the lack of obvious prostate gland structure existing in the said gland.