A rare primary leiomyosarcoma of the parotid gland: A case report and literature review

Background: Leiomyosarcoma of the head and neck region is very rare. Primary parotid leiomyosarcoma has only been reported nine times in the medical literature. Methods: A 68-year-old female presented with a left facial mass. Physical examination revealed a firm immobile mass at the level of the left parotid tail. No facial nerve dysfunction or palpable adenopathy was noted at the time of presentation. This patient underwent a superficial parotidectomy with a facial nerve dissection and left selective neck dissection. Results: Pathologic findings revealed a sarcoma of intermediate to high-grade, composed of spindle cells with herringbone pattern, eosinophilic fibrillary cytoplasm, and focal granularity. Immunohistochemistry was positive for vimentin and smooth muscle actin and negative for desmin, S100 and CD34. The findings are consistent with a leiomyosarcoma. Following complete surgical resection, adjuvant radiation therapy was administered. Conclusion: Primary sarcomas of the parotid gland, specifically parotid leiomyosarcomas, are extremely rare. Based on this patient's tumor size, grade and resectability, this case met the criteria for a primary leiomyosarcoma. We present only the tenth case of a primary parotid leiomyosarcoma to be reported in the English literature.