Fig. 1(A) Results of dual-priming oligonucleotide-polymerase chain reaction (wild) and direct sequencing (wild) in BRAF mutation-positive malignant melanoma case confirmed by cobas 4800 BRAF V600 mutation test. (B) Results of dual-priming oligonucleotide-polymerase chain reaction (failed) and direct sequencing (V600E) in BRAF mutation-positive malignant melanoma case confirmed by cobas 4800 BRAF V600 mutation test. (C) Results of dual-priming oligonucleotide-polymerase chain reaction (wild) and direct sequencing (V600K) in BRAF mutation-positive malignant melanoma case confirmed by cobas 4800 BRAF V600 mutation test.
Table 1.Frequency of BRAF mutation results by cobas observed in this study
Pathologic diagnosis and origin of tumor |
Case No. |
Tumors with BRAF mutation
|
Wild |
V600E |
V600K |
Malignant melanoma |
|
|
|
|
Primary |
Cutaneous |
12 |
6 (50.0) |
5 (41.7) |
1 (8.3) |
|
Mucosal |
8 |
7 (87.5) |
1 (12.5) |
0 |
|
Acral |
12 |
10 (83.3) |
2 (16.7) |
0 |
|
Unknown |
2 |
1 (50) |
1 (50) |
0 |
Total |
34 |
24 (70.6) |
9 (26.5) |
1 (2.9) |
Papillary carcinoma from thyroid |
16 |
3 (18.8) |
13 (81.2) |
0 |
Adenocarcinoma from colon |
11 |
11 (100) |
0 |
0 |
Clear cell carcinoma from skin |
1 |
1 (100) |
0 |
0 |
Mucinous adenocarcinoma from bladder |
1 |
1 (100) |
0 |
0 |
Epithelioid sarcoma |
1 |
1 (100) |
0 |
0 |
Table 2.Cases with discordant results in dual-priming oligonucleotide-polymerase chain reaction (DPO-PCR), direct sequencing, and cobas 4800 BRAF V600 mutation test
Case No. |
Tumor type |
DPO-PCR |
Sequencing |
cobas |
Site of organ obtained |
Tumor volume (%) |
Melanin pigments |
Necrosis (%) |
Lymphocytes content (%) |
DNA concentration (ng/μL) |
260/280 ratio |
6 |
Malignant melanoma |
Failed |
Mutant (V600E) |
Mutant |
Skin (thumb) |
70 |
Minimal |
0 |
5 |
42.7 |
1.53 |
7 |
Malignant melanoma |
Failed |
Mutant (V600E) |
Mutant |
Skin (scalp) |
95 |
Minimal |
0 |
< 5 |
8.3 |
0.88 |
27 |
Malignant melanoma |
Wild |
Wild |
Mutant |
Lymph node |
90 |
Minimal |
4 |
5 |
35.8 |
1.49 |
29 |
Malignant melanoma |
Wild |
Mutant (V600K) |
Mutant |
Lymph node |
50 |
Moderate |
2 |
50 |
26.5 |
1.45 |
42 |
Papillary carcinoma |
Wild |
Wild |
Mutant |
Thyroid |
40 |
No |
0 |
< 5 |
52.3 |
1.95 |
44 |
Papillary carcinoma |
Wild |
Wild |
Mutant |
Thyroid |
80 |
No |
0 |
< 5 |
60.8 |
1.98 |