Low-grade myofibroblastic sarcoma of the parapharyngeal space.

Low-grade myofibroblastic sarcoma was recently described as representing malignant mesenchymal tumours that show myofibroblastic differentiation; few cases have been reported. Here, a low-grade myofibroblastic sarcoma of the parapharyngeal space is described. A 42-year-old man presented with swelling on the right side of the temporal bone. Based on histological and immunohistochemical features, the diagnosis of low-grade myofibroblastic sarcoma was established. The tumour had invaded the orbit and the brain, and therefore surgical excision was not possible. There are thought to have been no cases affecting this region reported previously in the English-language literature.