The dermoscopic feature of yellow lobularlike structures has been described in sebaceous hyperplasia. The dermoscopic appearance of aggregated yellow globules with or without a central puncta and fine, nonarborizing blood vessels (“crown vessels”) is thought to be classic for sebaceous hyperplasia. However, these features are not limited solely to sebaceous hyperplasia (Figure 1). These structures may also be seen in nevus sebaceous of Jadassohn (Figure 2) and sebaceous adenoma (Muir-Torre syndrome) (Figure 3). Histopathologically, yellow lobules correspond to dermal conglomerations of sebaceous glands, a feature shared by these 3 lesions. Dermoscopically, small blood vessels may also be seen at the periphery of the yellow lobularlike structures, representing dermal vessels displaced by lobules of hyperplastic sebaceous glands. Thus, when yellow lobularlike structures are visualized on dermoscopy, the differential diagnosis includes not only sebaceous hyperplasia but also other conditions with sebaceous differentiation such as nevus sebaceous and sebaceous adenoma.
Kim NH, Zell DS, Kolm I, Oliviero M, Rabinovitz HS. The Dermoscopic Differential Diagnosis of Yellow Lobularlike Structures. Arch Dermatol. 2008;144(7):962. doi:10.1001/archderm.144.7.962