口腔に発生した脂肪肉腫の２例

Abstract

Liposarcoma is a malignant tumor of the soft tissues, but it is extremely rare in the oral cavity, particularly in the tongue. The tumor typically presents as a painless, slowly enlarging mass, and wide surgical excision is important for successful management. We describe 2 patients with liposarcoma involving the tongue and buccal region, with reference to the existing literature.Patient 1 was a 60-year-old woman with a mass arising in the right inferior surface of the tongue. The suspected clinical diagnosis was lipoma of the tongue. Patient 2 was a 42-year-old man with swelling of the right cheek. The suspected clinical diagnosis was pleomorphic adenoma of the buccal region. Tumor excision followed by rapid intraoperative pathological examination in both patients revealed no apparent malignancy. However, the postoperative histopathological diagnosis was well-differentiated liposarcoma in patient 1 and well-differentiated type liposarcoma with metaplastic bone formation in patient 2. We thus surgically excised the tumor with a wide safety margin in patient 1 and applied postoperative radiotherapy to the buccal cheek in patient 2. Both patients remain free of reccurence and metastasis.These findings show that low-grade well-differentiated liposarcoma can be difficult to distinguish from other types of lipoma.