[1] Sebaceous hyperplasia, primarily affecting older patients in high-concentration areas like the face, head, and neck, typically has a 2-4 mm diameter and causes no symptoms.

[2] Murine studies suggest topical irritants and carcinogens may contribute to sebaceous hyperplasia development, with immunosuppression with cyclopsporin A or HIV infection increasing the likelihood.

[6] Although the etiology is unknown, murine studies have revealed that topical irritants and carcinogens may be involved in the development of sebaceous hyperplasia.

[7][8] Immunosuppression with cyclopsporin A[9] or HIV infection increases the likelihood of developing sebaceous hyperplasia significantly.

[14][15] On dermatoscopy, a distinct asymmetrical milky-white structure known as the cumulus sign has been identified in cases with sebaceous hyperplasia.