title: Primary cutaneous myxoid melanoma: immunohistologic clues to a difficult diagnosis.
abstract: We describe a 25-year-old man with a primary cutaneous myxoid malignant melanoma and xeroderma pigmentosum. Histologically, the tumor had a lentiginous intraepidermal component and a dermal myxoid nodule containing fusiform cells with hyperchromatic nuclei and nuclear pseudoinclusions. Immunohistochemically, the tumor cells were positive for S-100 protein in both the epidermis and the dermis and did not stain with HMB-45, AE1-AE3, MNF 116, antiactin, or anti-p53 protein. Although this tumor is rare, it should be considered in the differential diagnosis of cutaneous myxoid lesions.
authors.affiliation: Department of Pathology, New York Hospital-Cornell University Medical Center, NY 10021.
authors.forename: V G
authors.initials: VG
authors.lastname: Prieto
authors.forename: A
authors.initials: A
authors.lastname: Kanik
authors.forename: S
authors.initials: S
authors.lastname: Salob
authors.forename: N S
authors.initials: NS
authors.lastname: McNutt
mesh_terms: D000328:Adult; D002467:Cell Nucleus / Q000648:ultrastructure; D003593:Cytoplasm / Q000648:ultrastructure; D003937:Diagnosis, Differential; D004817:Epidermis / Q000473:pathology; D006801:Humans; D002479:Inclusion Bodies / Q000648:ultrastructure; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008545:Melanoma / Q000473:pathology*; D009418:S100 Proteins / Q000032:analysis; D012878:Skin Neoplasms / Q000473:pathology*; D014983:Xeroderma Pigmentosum / Q000473:pathology
chemical_list: D009418:S100 Proteins