title: The \textit{BRAF} V600E mutation in single- institution study of Russian melanoma patients.
abstract: BACKGROUND
  The activating mutation BRAF V600E is considered to be a diagnostic cutaneous melanoma (CM) marker important for prognosis and targeted therapy.
  
  
  OBJECTIVE
  The aim of this study was to determine the frequency of the V600E mutation in CM patients in Russia and to estimate the influence of the BRAF gene mutation status on prognosis and clinical outcome.
  
  
  METHODS
  To ensure mutation detection in FFPE tissue, interlaboratory validation was performed using three different methods: allele-specific hybridisation on a biochip, allele-specific real-time PCR and, in some cases, direct sequencing.
  
  
  RESULTS
  Mutation V600E was detected in 49% of patients. The age of disease manifestation was significantly lower in mutated (MT) BRAF patients, and the median age difference between the wild-type (WT) and MT BRAF groups (P= 0.002) was 10 years. A tumour thickness more than 1 mm was also more frequently observed in the MT BRAF group (P= 0.059). Patients from the MT BRAF group were more likely to have ulceration compared to the WT group (P= 0.088). No statistically significant differences were found between the relapse-free, progression-free or overall survival of CM patients in the MT BRAF and WT BRAF groups.
  
  
  CONCLUSIONS
  The data obtained show that the V600E BRAF mutation occurred in about half of melanoma patients; it was associated with earlier manifestation of melanoma and likely with more aggressive clinical features.
authors.affiliation: Clinical Oncology Research Institute, N. N. Blokhin Russian Cancer Research Center of Russian Academy of Medical Sciences, Moscow, Russia.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Lyubchenko
authors.affiliation: Clinical Oncology Research Institute, N. N. Blokhin Russian Cancer Research Center of Russian Academy of Medical Sciences, Moscow, Russia.|Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Moscow, Russia.
authors.forename: Marina
authors.initials: M
authors.lastname: Emelyanova
authors.affiliation: Institute of Molecular Biology and Biophysics, Novosibirsk, Russia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Shamanin
authors.affiliation: Clinical Oncology Research Institute, N. N. Blokhin Russian Cancer Research Center of Russian Academy of Medical Sciences, Moscow, Russia.
authors.forename: Lev
authors.initials: L
authors.lastname: Demidov
authors.affiliation: Clinical Oncology Research Institute, N. N. Blokhin Russian Cancer Research Center of Russian Academy of Medical Sciences, Moscow, Russia.|Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Moscow, Russia.
authors.forename: Alexander
authors.initials: A
authors.lastname: Zasedatelev
authors.affiliation: Clinical Oncology Research Institute, N. N. Blokhin Russian Cancer Research Center of Russian Academy of Medical Sciences, Moscow, Russia.|Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Moscow, Russia.
authors.forename: Tatyana
authors.initials: T
authors.lastname: Nasedkina
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D019943:Amino Acid Substitution; D003062:Codon; D004252:DNA Mutational Analysis; D005260:Female; D005500:Follow-Up Studies; D005787:Gene Frequency; D006801:Humans; D008297:Male; D008545:Melanoma / Q000175:diagnosis / Q000235:genetics* / Q000401:mortality; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D011379:Prognosis; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D012426:Russia; D055815:Young Adult
chemical_list: D003062:Codon; D048493:Proto-Oncogene Proteins B-raf
keywords: BRAF gene; Cutaneous melanoma; V600E mutation; clinical features; molecular diagnostics