A patient presents with a gray lesion on the cheek that comes and goes. In the differential diagnosis, which diagnosis should be EXCLUDED because it occurs only on the palate?

Correct answer: C. Nicotine stomatitis

• A. Lichen planus can occur on the buccal mucosa and is a valid differential for gray/white cheek lesions.
• B. Fordyce spots are sebaceous glands visible on the buccal mucosa and lips — they are a valid finding there.
• C. Correct. Nicotine stomatitis (smoker's palate) occurs EXCLUSIVELY on the hard palate due to heat from pipe/cigar smoke pooling there. It presents as gray-white palatal mucosa with red dots (ductal openings). It CANNOT occur on the buccal mucosa — exclude it from the differential.
• D. Leukoplakia can occur on buccal mucosa and is a valid differential.