Malignant fibrous histiocytoma of the sinonasal tract

Background. Sinonasal malignant fibrous histiocytoma (MFH) is rare. Methods. Twenty-five patients were registered with a diagnosis of sinonasal MFH at our hospital in the past 30 years. Clinical data were retrospectively reviewed. Results. Eight tumors were primary MFH and 17 tumors were post-irradiated MFH, located within the radiation field for previous nasopharyngeal carcinoma. Twenty-one tumors originated from the maxillary sinus, 3 from the nasopharynx, and 1 from the nasal cavity. Twenty-three patients underwent surgery but only 12 tumors were removed completely. The 5-year overall and disease-free survival rates were 25.1% and 21.5%, respectively. Multivariate analyses showed that previous radiation was the only adverse prognostic factor for disease-free survival (p = .045). The 5-year disease-free survival rates of primary MFH and post-irradiated MFH were 72.9% and 0%. Conclusion. In this series, post-irradiated MFH was more common than primary MFH. The prognosis of post-irradiated MFH is poor, whereas primary MFH is fair.