A case of carcinosarcoma arising in the submandibular gland

We present a case of carcinosarcoma arising in the submandibular gland. A 57-year-old man consulted our department in January 2002 because of a swelling in the right submandibular region. He had a past history of a bladder tumor. On initial examination, we recognized induration coincident with the right submandibular gland and Wharton's duct. A biopsy specimen showed a malignant tumor. Magnetic resonance imaging showed no extra-glandular invasion of the tumor, and radioisotope studies demonstrated abnormal accumulation only in the right submandibular region. He underwent resection of the right side of the oral floor and submandibular triangle in March. Histopathological examination of the surgical specimen showed that the tumor consisted of three components, i. e., squamous cell carcinoma, adenocarcinoma, and sarcoma. On immunohistochemical studies, the sarcomatous component showed negative reactions for epithelial markers such as E29, CEA, MNF116, and AE1/AE3. We diagnosed the tumor as carcinosarcoma. Since local recurrence and metastases to the cervical lymph nodes occurred 3 months postoperatively, he underwent further surgery, i. e., radical neck dissection with resection of the oral floor, part of the tongue, and the mandible, followed by immediate reconstruction with a forearm free flap and titanium plate in July. Nine months after the second procedure, a computed tomographic scan showed metastases in the lung. Though he received anticancer drugs intravenously, metastases to the lung increased and further metastases appeared in the skull base, cervical vertebra, inguinal region, and liver. He died of MRSA pneumonia on June 1, 2004.