Malignant schwannoma and melanoma occurring in the maxilla.

A rare case of malignant melanoma of the hard palate following malignant schwannoma of the left maxilla in a 47-year-old woman is reported. Twenty-two months after surgical excision of malignant schwannoma with postoperative radiation and chemotherapy, malignant melanoma appeared with symptoms of gingival bleeding and swelling. Although the patient was treated by the partial maxillectomy with radical neck dissection and postoperative chemotherapy and adjuvant immunotherapy, she died of multiple distant metastases 9 months after the oral manifestation. A possible histological relationship of both tumors which are considered to be derived from the neural crest cells is also discussed.