A Guide to Yellow Oral Mucosal Entities: Etiology and Pathology

When faced with an uncertain clinical pathosis in the oral cavity, identifying the color of the mucosal lesion helps to narrow down a differential diagnosis. Although less common than red and white lesions, yellow lesions encompass a small group of distinct mucosal pathologic entities. Adipose tissue, lymphoid tissue, and sebaceous glands are naturally occurring yellow constituents of the oral cavity and become apparent with associated developmental or neoplastic lesions. Reactive and inflammatory lesions can create a yellow hue due to purulence, necrosis, and calcification. Some systemic diseases are known to deposit yellow bi-products such as amyloid or bilirubin into the oral mucosa of an affected person, and while not always yellow, unusual entities like verruciform xanthoma and granular cell tumor fall under the umbrella of yellow lesions given their occasional propensity to demonstration the color. This chapter aims to explore the unique group that is yellow lesions presenting in the oral mucosa.