Table 1 Description and summary of tumor histologies
Tumor histology | Overall cellular organization | Histology description | Cytokeratin staining |
|---|---|---|---|
Acinar | Well differentiated | Acini with bilayered, duct-like epithelial cells | Maintenance of ductal morphology with K8 cells surrounding clear lumens and K14 cells adjacent to the stroma |
Papillary | Well differentiated | Epithelial cell sheets, generally 2–3 layers thick, surrounded by stroma | Maintenance of luminal and basal cell organization with K14-positive cells adjacent to the stroma |
Solid adenocarcinoma | Poorly differentiated | Multilayered epithelial cells grouped in large units (>100 μm in diameter) surrounded by 1–2 layers of stromal cells | Primarily K8-positive with sparse K14-positive cells near stromal regions |
Squamous | Poorly differentiated | Adenocarcinoma with clusters of keratin pearls and sheets of squamous epithelia | Large solid areas of either K8- or K14-positive cells; K14 cells are localized near keratinized regions |
Lipid-rich | Poorly differentiated | Heavily vacuolated epithelial cells | Primarily K8-positive |
Sebaceous-like | Poorly differentiated | Epithelial cells with enlarged nuclei and foamy cytoplasms | Primarily K14-positive |