low-grade malignant tumor of subcutaneous soft tissues invading into the joints and tendons, composed of fibroblastic cells, often showing virallike inclusion in nuclei and large nucleoli, arranged in clusters of myxoid stroma and infiltrates of inflammatory cells. SYN: acral inflammatory myxoinflammatory fibroblastic sarcoma, inflammatory myxohyaline tumor of distal extremities with virocytes, inflammatory myxohyaline tumor.