Cystadenocarcinoma (adenocarcinoma NOS) is a rare disease among salivary tumors. We report a case of cystadenocarcinoma originating from the palatine gland, with references. A 69-year-old man with an increasing tumor in the right palate was referred to our department. The patient had a 35 × 20 × 5 mm dome-like mass on the right hard palate, with a smooth and partially blue-violet surface. Contrast-enhanced CT imaging showed a mass lesion with a well-defined boundary and bony resorption beneath the right hard palatine mucosa. Contrast-enhanced MRI imaging showed a mass lesion with a high signal on T2W1 and high ADC value, which had a marginal capsule and an internal septum structure. Biopsy indicated a low-grade salivary gland tumor including a mucoepidermoid carcinoma. The tumor was resected under general anesthesia with the diagnosis of a malignant salivary tumor on the right palate. The histopathological diagnosis was cystadenocarcinoma. At twenty-five months after surgery, no recurrence or metastasis has been observed.
