Glycogenic Acanthosis of the Lower Lip in a Young Adult

Lower-lip glycogenic acanthosis is exceptionally rare and can present as subtle multifocal whitish papules on the vermilion border. In a 23-year-old man, excisional biopsy confirmed glycogenic acanthosis (PAS-positive, diastase-sensitive intracytoplasmic glycogen) with concomitant melanosis, and upper endoscopy showed no features suggestive of Cowden syndrome/PTEN hamartoma tumor syndrome. Awareness of this presentation may facilitate accurate diagnosis and support appropriate syndromic evaluation when clinically indicated.