2018 Volume 64 Issue 3 Pages 153-158
We report a case of myxofibrosarcoma of the maxillary bone that showed extensive resorption of bone as an initial symptom. A 20-year-old man was referred to our hospital because of mobility of the right upper molar teeth. Computed tomography showed bone resorption of the right maxilla. An initial biopsy revealed the presence of inflammatory granulation tissue. Seven months after the first examination, newly formed bone appeared in the right maxilla. Subsequently, however, the patient stopped the examinations. Two years after the first examination, he revisited our hospital because of swelling of the right maxilla with spontaneous pain. A biopsy specimen was diagnosed as low-grade fibromyxoid sarcoma. Because surgical treatment was difficult, the patient received heavy particle radiotherapy in another facility. The tumor of the right maxilla then disappeared. However, wide bone necrosis and rupture of an internal carotid artery occurred as an adverse effect of the treatment. Three years 9 months after the first examination, the patient died of carcinomatous peritonitis. After death, application of new immunostaining and genetic analyses excluded the initial diagnosis. Instead, myxofibrosarcoma was diagnosed. In addition, we found a change from low-grade to high-grade malignancy.
