The so called “Malignant Fibrous Histiocytoma” is actually an Unusual Fibrosarcoma

Abstract

The so-called “malignant fibrous histiocytoma (MFH)” has become progressively more enigmatic since entering the soft tissue tumor field, based on tissue culture studies performed almost 50 years ago. It inexplicably evolved from an exceedingly common soft tissue diagnosis into a problematic diagnosis. Because of the conundrum, clinicians require that “malignant fibrous histiocytoma”, the name that they are familiar with, appears somewhere in the diagnosis. A recent review of the electron micrographs from 157 MFHs diagnosed over 32 years appears to explain how it was misnamed and its true identity, and as a consequence requires an updating of its clinico-pathologic correlation (CPC). It is an unusual fibroblastic entity that has the capacity to attract, activate, and stimulate fusion of normal macrophages.

• Fibroblasts
• fibrosarcoma
• histiocytes/macrophages
• malignant fibrous histiocytoma
• EMT
• multinucleated giant cell
• soft tissue tumor
• TEM