title: Heterogeneous Pathology of Melasma and Its Clinical Implications.
abstract: Melasma is a commonly acquired hypermelanosis that affects sun-exposed areas of the skin, with frequent facial involvement. Its histologic manifestations are evident in the epidermis, extracellular matrix, and dermis. In addition to epidermal pigmentation, pathologic findings of melasma include extracellular matrix abnormality, especially solar elastosis. The disrupted basement membrane has been described in melasma with variable incidences. In the dermis, an increase in vascularity and an increase in the number of mast cells were observed, indicating that dermal factors have critical roles in the pathogenesis of melasma, despite the fact that melasma is characterized by epidermal hyperpigmentation. This review discusses such histologic characteristics of melasma, with consideration to their implications for melasma treatment.
authors.affiliation: College of Medicine, Seoul National University, Jongro-gu, Seoul 03080, Korea. soonhyo17@hanmail.net.|Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do 13620, Korea. soonhyo17@hanmail.net.
authors.forename: Soon-Hyo
authors.initials: SH
authors.lastname: Kwon
authors.affiliation: College of Medicine, Seoul National University, Jongro-gu, Seoul 03080, Korea. 1polly@hanmail.net.|Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do 13620, Korea. 1polly@hanmail.net.
authors.forename: Young-Ji
authors.initials: YJ
authors.lastname: Hwang
authors.affiliation: College of Medicine, Seoul National University, Jongro-gu, Seoul 03080, Korea. drleesookeun@gmail.com.|Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do 13620, Korea. drleesookeun@gmail.com.
authors.forename: Soo-Keun
authors.initials: SK
authors.lastname: Lee
authors.affiliation: College of Medicine, Seoul National University, Jongro-gu, Seoul 03080, Korea. gcpark@snu.ac.kr.|Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do 13620, Korea. gcpark@snu.ac.kr.
authors.forename: Kyoung-Chan
authors.initials: KC
authors.lastname: Park
mesh_terms: D000287:Administration, Topical; D000975:Antioxidants / Q000008:administration & dosage / Q000627:therapeutic use; D001485:Basement Membrane / Q000378:metabolism / Q000473:pathology; D002738:Chloroquine / Q000008:administration & dosage / Q000627:therapeutic use; D020405:Dermis / Q000378:metabolism / Q000473:pathology; D019468:Disease Management; D005786:Gene Expression Regulation; D006801:Humans; D006873:Hydroquinones / Q000008:administration & dosage; D053685:Laser Therapy; D008407:Mast Cells / Q000378:metabolism / Q000473:pathology; D008548:Melanosis / Q000378:metabolism / Q000473:pathology* / Q000628:therapy*; D010789:Phototherapy
chemical_list: D000975:Antioxidants; D006873:Hydroquinones; D002738:Chloroquine; C031927:hydroquinone
keywords: basement membrane; histopathology; mast cells; melasma; photoaging; vascularization