Table 1: Summary of studies evaluating
BRAFV600E mutation status in LCH. NT:
not tested; WT: wild-type BRAF
allele.
|
Study |
All Sites |
Cutaneous LCH |
Method |
||
|
Immunohistochemistry |
Molecular |
Immunohistochemistry |
Molecular |
||
|
Badalian-Very, et al. [6] |
NT |
35/61
BRAFV600E (57%) 26/61
WT (43%) |
NT |
1/1
BRAFV600E (100%) |
Pyrosequencing and Mass Spectrometric Genotyping |
|
Satoh,
et al. [9] |
NT |
9/16
BRAFV600E (56%) 5/16 WT
(31%) 1/16 BRAF 600DLAT‡ (6%) 1/16 BRAF T599A (6%) |
NT |
2/3
BRAFV600E (67%) 1/3 BRAF T599A (33%) |
Pyrosequencing |
|
Sahm, et al. [8] |
34/89*
(38%) |
18/46
BRAFV600E* (39%) 1/46
BRAFV600K (2%) 27/46
WT (59%) |
1/5
(20%) |
4/4 WT
(100%) |
Bidirectional
Direct Sequencing |
|
Haroche, et al. [7] |
NT |
11/29
BRAFV600E (38%) 18/29
WT (62%) |
NT |
1/1 WT
(100%) |
Pyrosequencing |
|
Mehes, et al. [15] |
8/15
(53%) |
7/15
BRAFV600E (47%) 8/15 WT
(53%) |
NT |
NT |
Direct
Sequencing |
|
Tong, et al. [24] |
NT |
0/18
BRAFV600E (0%) 18/18
WT (100%) |
NT |
0/7
BRAFV600E (0%) 7/7 WT
(100%) |
Direct
Sequencing |
|
Varga, et al. [25] |
NT |
NT |
NT |
6/11 BRAFV600E (55%) |
Direct
Sequencing |
WT, wild-type BRAF allele.
†BRAFV600E mutation
testing on blood from 13 additional patients with skin involvement (not listed)
revealed all patients (13/13, 100%) to be WT.
‡600DLAT is an in-frame
insertion which leads to insertion of 4 additional amino acids beginning at
codon 600, effectively resulting in a BRAFV600D
substitution that mimics the structural and functional consequences of BRAFV600E.
*BRAFV600E IHC was
positive (concordant) in all 18 cases in which the V600E mutation was
identified by molecular analysis; 1 case was positive by IHC but was WT for the
BRAF allele; V600K was identified by
mutational analysis in 1 case, and IHC was appropriately negative in this case;
The remaining 26 cases in which IHC and mutational status were evaluated
harbored the WT allele and IHC was concordantly negative.