Metastasis of leiomyosarcoma to the sublingual region

Metastasis of malignant tumors to the oral cavity is rare, and few cases of metastasis of leiomyosarcoma to the oral cavity have been reported. Here, we report a case of leiomyosarcoma metastasizing to the sublingual region. The patient visited our gastroenterology clinic in September 2012 because of an abdominal mass. Masses were found in the retroperitoneum, liver S2, and small intestine, and resection was performed in November 2012 at our Department of Surgery. The patient was diagnosed with leiomyosarcoma based on the histopathological findings. The leiomyosarcoma continued to metastasize to the liver and retroperitoneum, as well as subcutaneously and intramuscularly, and was resected three times in 2013. In December 2014, the patient became aware of a lump in the sublingual region, and positron emission tomography (PET)-CT indicated a metastatic tumor. The patient was referred to our department for examination. A mass, the size of a chicken egg, was palpated in the midline of the sublingual region, and magnetic resonance imaging indicated a 27 x 21 mm mass with heterogeneous enhancing effects. In February 2015, the tumor was resected under general anesthesia based on the diagnosis of suspected sublingual metastasis of leiomyosarcoma. Histopathological examination indicated a leiomyosarcoma consisting of spindle-shaped, partially polymorphous proliferating tumor cells. The tumor was pathologically and immunohistochemically identical to previously resected tumors. After the surgery, there was no recurrence in the sublingual region; however, the patient died in February 2020, 8 years after the initial diagnosis.