Primary leiomyosarcoma of the submandibular gland: a case report.

BACKGROUND: Leiomyosarcoma is a rare malignant mesenchymal tumor that represents 5-7 % of all soft tissue sarcomas. The occurrence of this tumor in the salivary glands is exceptional. Only five cases are reported in the submandibular gland.

CASE PRESENTATION: A 65-year-old white Moroccan woman presented with a history of progressive right submandibular swelling which had grown over a period of 8 months. Clinical examination showed a submandibular painless, mobile and hard mass without cervical lymphadenopathy. Ultrasonography and computed tomography revealed a solid and heterogeneous mass measuring 4 × 2 cm involving the submandibular gland. A resection of the gland was performed. Pathological findings were consistent with primary leiomyosarcoma of the submandibular gland. No recurrence occurred after two months of follow-up.

CONCLUSION: Primary leiomyosarcoma of the submandibular gland is an extremely rare mesenchymal tumor. Clinical and radiological features are not specific. Differential diagnosis includes metastatic leiomyosarcoma and gastrointestinal stromal tumor, myoepithelioma, sarcomatoid carcinoma, melanoma and other sarcomas. Little is known about the overall biologic behavior of this tumor, but the prognosis seems to be poor.