High power: DQ stain
Loosely cohesive clusters of small blue cells with nuclear molding
High power: DQ stain
Loosely cohesive clusters of small blue cells with nuclear molding
Low power: Pap stain
Loosely cohesive clusters of small blue cells
Note numerous naked nuclei in background
Medium power: Pap stain
Small round blue cell tumor with round to oval nuclei, granular chromatin and vacuolated cytoplasm
Medium power: Pap stain
Small round blue cell tumor with round to oval nuclei, granular chromatin and vacuolated cytoplasm
Note necrosis in the background
Medium power: Pap stain
Desmoplastic small round cell tumor with round to oval nuclei, granular chromatin and vacuolated cytoplasm
Note necrosis in the background
Medium power: Pap stain
Small cluster of DSRCT cells
High power: Pap stain
Round to oval nuclei with irregular nuclear outlines, granular chromatin, inconspicuous nucleoli
Features
• Moderately cellular
• Small blue cells and stromal fragments
• Loosely cohesive clusters, rosettes and gland-like structures
• Small blue cells
• Scant to moderate vacuolated cytoplasm
• May have rhabdoid cells
• Sometimes fibroblast-like spindle cells
• Round to oval nuclei
• Naked nuclei may be present
• Granular chromatin
• Inconspicuous nucleoli
• Nuclear molding may be present
• Metachromatic stromal fragments
• Mitosis and necrosis often seen
• IHC: Usually expresses cytokeratin, desmin, vimentin, EMA, CD56, WT- 1, synaptophysin (+/- ), CD99 (+/- )
• Translocation t(11;22) EWS:WT1
Crapanzano JP et al. Cancer. 2002 Feb 25;96(1):21-31.