放射線誘発が疑われた上顎部筋線維肉腫の1例 A case of myofibroblastic sarcoma in the maxillary region suspected to be radiation-induced
Myofibroblastic sarcoma is an extremely rare malignant tumor in the oral and maxillofacial region. We report a case of myofibroblastic sarcoma probably induced by irradiation for maxillary sinus cancer. The patient was a 61-year-old man whose present history was as follows. In October 1989, he presented with pain in the left maxillary molar region. A squamous cell carcinoma of the left maxillary sinus was diagnosed, and he was treated with external irradiation of 50Gy combined with chemotherapy. Left maxillectomy was done in February 1990.<BR>The postoperative course was satisfactory. However, in June 1998, he presented again with a tumor arising in the posterior region of the defect on the left side of the maxilla. Although histopathological examination of a biopsy specimen revealed granulation tissue with inflammatory changes, the tumor grew rapidly. The tumor was therefore suspected to be malignant and was resected under general anesthesia. Histopathological examination revealed atypical and spindle tumor cells with immunohistochemically positive staining for a-smooth muscle actin, desmin, vimentin, and muscle specific actin, but negative staining for h-caldesmon.<BR>On the basis of these histopathological and clinical findings, a final diagnosis of a myofibroblastic sarcoma of the maxillary region was made. The lesion was strongly suspected to be a radiation-induced tumor. The patient was followed up for 4 years 5 months after operation. The subsequent course was satisfactory, with no signs of recurrence or distant metastasis.
日本口腔外科学会雑誌 50(9), 538-541, 2004-09-20
Japanese Society of Oral and Maxillofacial Surgeons