Katherine Kasper, MD
Fellow, Dept. of Cytopathology
Northwestern University, Feinberg School of Medicine, Chicago, IL, USA

CASE HISTORY: 
The patient is a 46 year-old male with a history of recent hemorrhagic stroke undergoing rehabilitation, who was found to have right medial thigh swelling. CT imaging revealed an approximately 4 cm soft tissue lesion, suspected radiographically to be myonecrosis. Ultrasound-guided core biopsy was performed. Touch preparations were made during on site adequacy evaluation/triage by Cytopathology.

Fig. 1. DQ stained touch preparations	Fig. 2. H & E stained core biopsy
Fig. 3. H & E stained core biopsy	Fig. 4. H & E stained core biopsy
Fig. 5. FNA case and surgical excision of Myositis ossificans showing zonal phenomenon with a mixed cytomorphological patterns including myxoid (upper right); edematous (upper left); bone tissue (lower left), inflammatory cells; hypocellular areas, and hypercellular areas. The proliferating cells are mixture of spindle, stellate fibroblasts and giant cells. (Courtsey: Dr Walid Khalbuss)

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