Primary intraoral leiomyosarcoma of the tongue: an immunohistochemical study and review of the literature

Leiomyosarcoma is a relatively uncommon mesenchymal tumor that exhibits smo oth-muscle differentiation. We report a new case of leiomyosarcoma involvin g the tongue of a 67-year-old male. Histologically, the tumor was composed of variably oriented fascicles of spindle-shaped cells with 'cigar-shaped' nuclei and eosinophilic cytoplasm, containing occasional PAS-positive granu les. Atypical mitotic figures and necrotic foci were frequently detected. C onsistent desmin, cc-smooth muscle-specific and sarcomeric actin, and vimen tin immunoreactivity was demonstrated in the tumor cells, whereas cytokerat ins, CD 30, CD 31, CD 34, CD 45, CD 68, EMA. GFAP, HMB 45 and S-100 protein were negative. The patient underwent wide surgical excision of the tumor a nd is alive and disease-free at a 5-year follow-up. This report emphasizes the difficulties in the differential diagnosis of these uncommon tumors in an intra-oral location, (C) 2000 Elsevier Science Ltd. All rights reserved.