What is a Malignant Fibrous Histiocytoma?

A malignant fibrous histiocytoma, or MFH, is a cancer that grows from soft tissues or bone. It is a member of a group of cancers known as sarcomas, and malignant fibrous histiocytoma is the most commonly occurring soft tissue sarcoma found in the older adult population. Treatment usually involves surgery and radiotherapy, and sometimes chemotherapy. A cure is possible if the cancer can be fully removed before it has spread.

The first sign of a malignant fibrous histiocytoma is typically a lump, or tumor, which is painless and seen to be enlarging. It occurs most often on an arm or leg, although the cancer can originate in any area of the body. A magnetic resonance imaging scan, or MRI scan, is often used to obtain an image of the tumor, giving an indication of its structure and the extent of its spread. In order to study the actual tumor cells which distinguish malignant fibrous histiocytoma from other types of cancer, a biopsy is usually necessary. Here, a needle is introduced into the tumor and a sample of cells is removed which can then be examined under a microscope.

Cases of malignant fibrous histiocytoma have a variable outlook depending on whether the tumor has already spread to other parts of the body, and how large and aggressive the cancer is. Bigger and more aggressive tumors lead to lower survival rates, and if the cancer has spread, or metastasized, this means the prognosis is poor. The most common area of the body to which malignant fibrous histiocytoma spreads is the lungs.

Surgery is the main type of treatment associated with malignant fibrous histiocytoma, and while in the past this could involve amputation of an affected limb, this is now uncommon and the limb is usually saved if possible. Radiation therapy is generally given in addition, and this treatment may be carried out either before, during, or as is most frequent, after the surgical operation. Chemotherapy is not always beneficial, but it may be useful in some cases, and research is ongoing into new and potentially more effective modes of treatment for this type of cancer using chemotherapy.

Malignant fibrous histiocytoma has been reclassified by the World Health Organization as it is now thought to represent the end stage in the development of a number of different types of tumor, rather than being a disease in its own right. It is now referred to as an "undifferentiated pleomorphic sarcoma, not otherwise specified." In spite of this, the original name is still being used by doctors and their patients.