Molecular analysis of BRAF V600E mutation in multiple nodules of pulmonary Langerhans cell histiocytosis

Virchows Arch. 2017 Apr;470(4):429-435. doi: 10.1007/s00428-017-2092-4. Epub 2017 Feb 20.

Abstract

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare, smoking-related histiocytic disorder with variable clinical symptoms. Like in other non-pulmonary Langerhans cell proliferations, PLCH has recently been shown to harbour BRAF V600E mutations in a significant subset of cases, thus challenging the concept of PLCH being a reactive disorder. Here, we analysed 38 formalin-fixed and paraffin-embedded PLCH nodules of nine patients for BRAF mutation using two different molecular methods. Using pyrosequencing and allele-specific quantitative PCR (AS-PCR), BRAF V600E mutations were found in 16/38 (42%) and 31/37 (84%) nodules, respectively. Analysing different nodules of the same patients with pyrosequencing 3/6 patients showed a concordant BRAF mutation status. When allele-specific quantitative PCR was used, condordant results were found in 5/6 patients. Our findings clearly indicate that (a) the sensitivity of the method used is crucial in analysing BRAF mutation status, (b) AS-PCR is more sensitive in detecting BRAF V600E mutations than pyrosequencing,

Keywords: Allele-specific quantitative PCR; BRAF-mutation; Clonality; Pulmonary Langerhans cell histiocytosis; Pyrosequencing.

MeSH terms

  • Adult
  • Aged
  • DNA Mutational Analysis / methods*
  • Female
  • Histiocytosis, Langerhans-Cell / genetics*
  • Histiocytosis, Langerhans-Cell / pathology*
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Mutation
  • Polymerase Chain Reaction / methods*
  • Proto-Oncogene Proteins B-raf / genetics*
  • Sensitivity and Specificity

Substances

  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf