Test Details: Desmin is a type III intermediate filament protein present in intercalated disks and Z-lines of cardiac muscle and Z-line of skeletal muscle. Desmin stains cardiac, skeletal, and smooth muscle cells and tumours derived from these cells. The intensity of desmin expression correlates with the differentiation grade of muscle or muscle tumour. Desmin is an important diagnostic marker for all myogenic tumours and tumours with myogenic differentiation.