title: A Symmetric Eczematous Eruption Harboring Thousands of Melanocytic Lesions.
abstract: The abrupt appearance of melanocytic lesions is a unique phenomenon that can occur in the setting of eruptive nevi or epidermotropic melanoma metastases.
  
  
  
  To examine the immunohistochemical and genetic mutative features of a novel case of an eczematous reaction followed by the abrupt appearance of melanocytic lesions.
  
  
  
  Case report of a 48-year-old woman with no significant medical history who first presented with an eczematous dermatitis on her torso, extremities, and buttocks and who subsequently developed thousands of pinpoint, histologically atypical melanocytic tumors and invasive melanoma within the areas of inflammation.
  
  
  
  Immunohistochemical and mutational analyses of the patient's melanocytic tumors were conducted.
  
  
  
  Mutational analysis of the pigmented lesions did not identify any activating mutations in BRAF, PTEN, NRAS, KRAS, and HRAS. Immunohistochemical analyses of 9 biopsied pigmented lesions all showed normal expression of the tumor suppressors p16 and PTEN and no expression of mutated BRAF V600E protein.
  
  
  
  To our knowledge, this is a previously unreported eruption comprising 2 distinct components: an eczematous reaction and a wave of melanocytic proliferations within the inflammatory regions. Possible explanations for this patient's condition, include immune stimulation leading to nevogenesis, benign "nevic" metastases, eruptive nevi, and epidermotropic metastatic melanoma.
authors.affiliation: Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ratushny
authors.affiliation: Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kraft
authors.affiliation: Department of Dermatology, Lahey Hospital and Medical Center, Burlington, Massachusetts.
authors.forename: Samuel L
authors.initials: SL
authors.lastname: Moschella
authors.affiliation: Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston.
authors.forename: Lyn M
authors.initials: LM
authors.lastname: Duncan
authors.affiliation: Department of Medicine, Division of Hematology/Oncology, Massachusetts General Hospital and Harvard Medical School, Boston.
authors.forename: Donald P
authors.initials: DP
authors.lastname: Lawrence
authors.affiliation: Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston.
authors.forename: Hensin
authors.initials: H
authors.lastname: Tsao
mesh_terms: D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis; D004485:Eczema / Q000150:complications*; D005260:Female; D020558:GTP Phosphohydrolases / Q000235:genetics; D006801:Humans; D008545:Melanoma / Q000737:chemistry* / Q000150:complications / Q000235:genetics* / Q000473:pathology; D008565:Membrane Proteins / Q000235:genetics; D008875:Middle Aged; D009508:Nevus, Pigmented / Q000737:chemistry* / Q000150:complications / Q000235:genetics / Q000473:pathology; D051059:PTEN Phosphohydrolase / Q000032:analysis / Q000235:genetics; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics; D012878:Skin Neoplasms / Q000737:chemistry* / Q000150:complications / Q000235:genetics* / Q000473:pathology
chemical_list: C000614131:CDKN2A protein, human; D019941:Cyclin-Dependent Kinase Inhibitor p16; C117307:KRAS protein, human; D008565:Membrane Proteins; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human; D020558:GTP Phosphohydrolases; C579846:NRAS protein, human; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)