Vascular proliferation caused by human herpesvirus-8 (HHV-8). It is considered a low-grade malignant vascular tumor. There are four recognized clinical subsets of Kaposi’s sarcoma: classic, endemic, iatrogenic, and HIV related. Clinically the cutaneous lesions begin as reddish-blue macules or plaques that gradually enlarge and become nodular.
- Homogeneous pattern with differing colors (i.e., whitish, pinkish, reddish, bluish, or violaceous) in different lesions in the same patient.
- Rainbow-like appearance: multicolored areas showing various colors of the rainbow spectrum. This sign is not pathognomonic of Kaposi’s sarcoma and it is only seen with polarized light dermoscopy.
- Whitish structureless areas, vascular structures, scale, and a white collarette may also be seen.
- Cheng et al.: Rainbow pattern in Kaposi's sarcoma under polarized dermoscopy: a dermoscopic pathological study. Br. J. Dermatol. 2009;160:801-9. PMID: 19067686. DOI.
- Vázquez-López et al.: Dermoscopic rainbow pattern in non-Kaposi sarcoma lesions. Br. J. Dermatol. 2009;161:474-5. PMID: 19438855. DOI.