title: Differential diagnosis in primary and metastatic cutaneous melanoma by FT-Raman spectroscopy.
abstract: OBJECTIVE
  To qualify the FT-Raman spectral data of primary and metastatic cutaneous melanoma in order to obtain a differential diagnosis.
  
  
  METHODS
  Ten normal human skin samples without any clinical or histopathological alterations, ten cutaneous melanoma fragments, and nine lymph node metastasis samples were used; 105, 140 and 126 spectra were obtained respectively. Each sample was divided into 2 or 3 fragments of approximately 2 mm³ and positioned in the Raman spectrometer sample holder in order to obtain the spectra; a monochrome laser light Nd:YAG at 1064 nm was used to excite the inelastic effect.
  
  
  RESULTS
  To differentiate the three histopathological groups according to their characteristics extracted from the spectra, data discriminative analysis was undertaken. Phenylalanine, DNA, and Amide-I spectral variables stood out in the differentiation of the three groups. The percentages of correctly classified groups based on Phenylalanine, DNA, and Amide-I spectral features was 93.1%.
  
  
  CONCLUSIONS
  FT-Raman spectroscopy is capable of differentiating melanoma from its metastasis, as well as from normal skin.
authors.affiliation: UNIFESP, Sao Paulo, Brazil. dra.afo@gmail.com
authors.forename: Andrea Fernandes de
authors.initials: AF
authors.lastname: Oliveira
authors.forename: Ivan Dunshee de Abranches Oliveira
authors.initials: ID
authors.lastname: Santos
authors.forename: Sidney Bandeira
authors.initials: SB
authors.lastname: Cartaxo
authors.forename: Renata Andrade
authors.initials: RA
authors.lastname: Bitar
authors.forename: Mílvia Maria Simões e Silva
authors.initials: MM
authors.lastname: Enokihara
authors.forename: Herculano da Silva
authors.initials: Hda S
authors.lastname: Martinho
authors.forename: Airton Abrahão
authors.initials: AA
authors.lastname: Martin
authors.forename: Lydia Masako
authors.initials: LM
authors.lastname: Ferreira
mesh_terms: D000577:Amides / Q000032:analysis; D004247:DNA / Q000032:analysis; D003937:Diagnosis, Differential; D006801:Humans; D008545:Melanoma / Q000737:chemistry / Q000175:diagnosis* / Q000556:secondary; D010649:Phenylalanine / Q000032:analysis; D012867:Skin / Q000737:chemistry; D012878:Skin Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000473:pathology; D013059:Spectrum Analysis, Raman / Q000379:methods / Q000592:standards*
chemical_list: D000577:Amides; D010649:Phenylalanine; D004247:DNA