Malignant fibrous histiocytoma at site of bone infarction in association with DCS

A malignant fibrous histiocytoma developed at the site of bone infarction in the right femur of a 51-year-old male who had worked as a helmet diver and had experienced two episodes of bends in his young days. The outcome was rapidly fatal despite amputation of the right thigh, and widespread metastasis was noted at the time of autopsy. Histopathological examination of the amputated femur disclosed an intimate relation between the old focus of bone infarction and the tumor tissue, which was composed of a mixture of fibroblast-like cells and histiocyte-like cells. In an analysis of the published cases of malignant fibrous histiocytoma associated with bone infarction, it was found that the patients with bone infarction who had worked under hyperbaric atmosphere are at the risk of developing such a malignant tumor. The prolonged reparative process following bone infarction seems to be an important factor in the pathogenesis of malignant fibrous histiocytoma.