HAIRY CELL LEUKAEMIA (HCL)

BRAF p.V600E Variant Testing

The BRAF p.V600E variant has been reported to be present in Classic Hairy Cell Leukaemia but not in other peripheral B-cell lymphomas or leukaemias with similar clinical and morphologic features, including VH4-34+HCL, HCL variant, splenic marginal zone lymphoma or unclassified splenic lymphomas or leukaemias (Tiacci et al. 2011 NEJM 24: 2305-2315, Arcaini et al. 2012 Blood 119:188-191, Xi et al. 2012 Blood 119:3330-3332). The BRAF p.V600E variant has been identified in 57% of patients with Langerhan’s cell histocytosis (Badalian-Very et al. 2010 Blood: 116 1919-1923).

BRAF p.V600E variant analysis can therefore be used as a tool in the differential diagnosis of Classic Hairy Cell Leukaemia. However, the use of this variant for diagnostic purposes MUST be interpreted in combination with clinical and morphologic features.

BRAF p.V600E variants are identified by bi-directional DNA sequencing, which will detect variants present at a level of greater than 10%.

Laboratory contact: Dr Caroline Wickham 01392 408252 caroline.wickham@nhs.net Clinical contact: Dr Paul Kerr 01392 402917 paul.kerr1@nhs.net

 

The laboratory participates in the UK NEQAS LI BRAF V600E Detection EQA scheme.