A patient has a small bump on the palate. Which of the following would be LEAST likely in the differential diagnosis?

Correct answer: C. Incisive canal cyst (nasopalatine duct cyst)

• A. INCORRECT (torus palatinus IS a common differential). Torus palatinus is the most common exostosis of the oral cavity, occurring in the midline of the hard palate. It presents as a firm, bony bump and is a very common palatal finding.
• B. INCORRECT (minor salivary gland tumor IS a differential). The hard palate is the most common site for minor salivary gland tumors. The posterior lateral hard palate contains numerous minor salivary glands, and neoplasms (both benign and malignant) must be included in any palatal mass differential.
• C. CORRECT — LEAST likely. While the nasopalatine duct cyst (incisive canal cyst) is the most common non-odontogenic cyst of the jaws, it typically presents as a radiolucent cystic lesion (detected on radiographs) near the incisive foramen. It may produce a swelling of the anterior palate that can be seen clinically as a small bump, but it's primarily a radiographic finding. However, for a surface bump on the palate, the incisive cyst (which is intraosseous) would be less commonly the first differential compared to surface lesions. The source answer is 'incisive cyst' as the exception.
• D. INCORRECT. Mucocele (mucus retention cyst) from minor salivary glands can occur on the palate, though less commonly than on the lower lip. It presents as a fluctuant, bluish nodule and should be included in the differential.