Multinodular
Clusters of histiocytes with abundant eosinophilic cytoplasm; monomorphic round-ovoid nuclei with prominent nucleoli and inconspicuous mitotic activity
Occasional interspersed osteoclast-type giant cells
Desmoplastic background
Multinodular
Clusters of histiocytes with abundant eosinophilic cytoplasm; monomorphic round-ovoid nuclei with prominent nucleoli and inconspicuous mitotic activity
Rare interspersed osteoclast-type giant cells frequently surrounded by small pools of erythrocytes
Siderophages and haemosiderin deposition
Desmoplastic background
Multinodular
Clusters of histiocytes with abundant eosinophilic cytoplasm; monomorphic round-ovoid nuclei with prominent nucleoli and inconspicuous mitotic activity
Interspersed osteoclast-type giant cells frequently surrounded by small pools of erythrocytes
Siderophages and haemosiderin deposition
Desmoplastic background; vascular invasion
Multinodular
Clusters of spindle cells with fascicular pattern; eosinophilic cytoplasm; ovoid nuclei with mild atypia and inconspicuous mitotic activity
Interspersed osteoclast-type giant cells
Myxoid-collagenous stroma; focal metaplastic bone