Yukio Yoshioka, Yasutaka Hayashido, Koh-ichi Koizumi, Yasufumi Myoishi, Tomoaki Hamana, Hisataka Kitano, Tetsuji Okamoto
Department of Molecular Oral Medicine and Maxillofacial Surgery, Division of Frontier Medical Science, Graduate School of Biomedical Sciences Hiroshima University, Hiroshima, Japan

Abstract
Leiomyosarcoma of the oral cavity is a rare malignant mesenchymal tumour. This report is of a 60-year-old woman with a leiomyosarcoma involving the mandible. Histologically, the tumour was composed of spindle-shaped cells with oval nuclei and eosinophilic cytoplasm, and atypical mitotic figures were detected. Immunoreactivity for desmin, vimentin, and α-smooth muscle actin was observed. The patient underwent wide surgical excision of the tumour. No sign of tumour recurrence or distant metastasis was observed 29 months after the operation.

Key words: Desmin, Immunohistochemistry, Leiomyosarcoma, Mandible, Smooth muscle actin, rat

Asian J Oral Maxillofac Surg. 2005;17:131-134.