Low power: Pap stain
Spindle cells admixed with epithelial cells with nuclear pleomorphism.
High power: Pap stain
Epithelial and spindle cells with high N:C ratios and multiple mitotic figures.
Low power: Pap stain
Fibromyxoid matrix (mesenchymal elements) admixed with epithelial fragments. Note numerous single cells and high grade features in the epithelial cells.
Features
• Heterogeneous tumors
• Dual cell population (adeno and squamous, epithelial and mesenchymal)
• Subtypes: adenosquamous carcinoma, carcinosarcoma and sarcomatoid carcinoma
• Epithelial cells with high N:C ratio
• Squamous components have dense squamoid cytoplasm
• Spindle cells bland to bizarre
• Enlarged pleomorphic nuclei
• May have spindled nuclei
• Fibromyxoid / cartilageous matrix
• Mitoses present
• Necrosis present
• Express cytokeratin, vimentin, may express SMA, S100, CD10, CK7, CK18
Kline TS et al. Diagn Cytopathol. 1990;6(1):63-7.
Stanley MW et al. Diagn Cytopathol. 1989;5(1):22-8.