Fibrosarcoma

Malignant spindle cell neoplasm with a characteristic herringbone pattern of growth. The widespread use of this term is discouraged and the term Malignant spindle cell neoplasm, unclassified is favored as no diagnostic criteria (in the absence of thorough immunoperoxidase staining and analysis) separate spindle cell melanoma and squamous cell carcinoma among others, from "fibrosarcoma"