A rare case of intravascular solitary fibrous tumor from the internal jugular vein to the sigmoid sinus

We report a rare case of intravascular solitary fibrous tumor （SFT） from the internal jugular vein to the sigmoid sinus, which has been followed over nine years. A 51-year-old woman was referred to our hospital, pre-senting with fullness of the right ear and swelling of the right neck. On imaging study, a tumor occupying from the right supraclavicular to the skull base, through the jugular foramen was found. The biopsy specimen of the intravascular tumor of the right jugular vein was initially diagnosed as epithelioid hemangioendothelioma （EHE）. The tumor increased in size at first, and after two courses of S-1 therapy （Tegafur, a prodrug of 5-fluorouracil, and 5-chloro-2-4-dihydroxypyridine）, the intravascular tumor in the right jugular vein had disappeared, whereas the lesion at the skull base remained stationary. This remaining lesion had gradually enlarged over the next 3—4 years, causing Ⅶ—Ⅻ cranial nerve paralysis. Radiation therapy was administered, and arytenoid adduc-tion and nerve-muscle pedicle flap implantation were performed for laryngeal paralysis. Over 5-year follow-up observation after irradiation, the remaining lesion at the skull base gradually diminished each year. Afterward, the histopathological findings of the biopsy specimen were reviewed and a revised diagnosis of intravascular SFT was made. Intravascular SFT is extremely rare, and the effects of chemotherapy or radiotherapy for a malignant soft tissue tumor are controversial, however, S-1 therapy and radiation therapy were successful in this case.