Table 1. Key pathologic and immunohistochemical features contrasting PDA, PAA, IDAC-P and HGPIN.
| Characteristics | PDA | PAA | IDAC-P | HGPIN |
|---|---|---|---|---|
| Cellular shape | Columnar | Cuboidal | Cuboidal | Cuboidal |
| Nuclear shape | Elongated & oval | Round | Round | Round |
| Nuclear size | 2–3× normal acinar cell | Enlarged, usually 2× normal acinar cell | At least 6× normal acinar cell | Enlarged, usually 2× normal acinar cell |
| Cribriform pattern | +, slit-like lumens | +, round lumens | +, round lumens | rare + |
| True papillae with fibrovascular cores | usually + | −, tufts of cells | −, tufts of cells | −, tufts of cells |
| Basal cells | −/+, few | − | +, at least focal | + |
| IHC for p63 & HMWCK | −/+, weak & patchy | − | +, patchy | + |
PDA, prostatic ductal adenocarcinoma; PAA, prostatic acinar adenocarcinoma; IDAC-P, intraductal adenocarcinoma of prostate; HGPIN, high-grade prostatic intraepithelial neoplasia; IHC, immunohistochemistry; HMWCK, high molecular weight cytokeratin.