Salivary gland cancer is a cancer that forms in tissues of a salivary gland. The salivary glands can be called major and minor. The major salivary glands consist of the parotid, submandibular, and sublingual glands. The minor glands include small mucus-secreting glands located throughout the palate, nasal and oral cavity. Salivary gland cancer is rare, with 2% of head and neck tumors forming in the salivary glands, the majority in the parotid.