BRAF Gene Mutation Analysis

Medical Test

• Determining eligibility of and monitoring treatment with anti-EGFR therapy (cetuximab and panitumumab)
• As an aid in diagnosis and management of melanoma
• As an aid in diagnosis and management of colorectal cancer
• As an aid in diagnosis and management of lung cancer
• As an aid in diagnosis and management of thyroid cancer
• Therapy monitoring and disease management

• If either the BRAF V600E mutation or MLH1 promoter methylation is found in a microsatellite unstable tumor, then the tumor is probably sporadic and further work-up for HNPCC may not be warranted.
• If no BRAF mutation or MLH1 methylation is found, then the tumor may be either sporadic or inherited, and further work-up for HNPCC is recommended. It is known now that the BRAF p.V600E mutation is detected in more than 70% tumors with loss of MLH1 due to promoter hypermethylation but is rarely detected in tumors with a germline MLH1 gene mutation. Thus, a germline mutation within the MLH1 gene is very unlikely in this case.
• When testing is performed for therapeutic selection, especially for the efficacy of EGFR-targeted therapies in colorectal cancer, tumors lacking KRAS and BRAF might not be the best choice and may have limited therapeutic value for this patient.
• Detection of BRF V600 mutation in melanoma might indicate good respond to BRAF targeted therapy.

Positive :

• Melanomas
• Colorectal cancer
• Lung cancer
• Ovarian cancer
• Thyroid gland cancer
• Acute myeloid leukemia
• Glioma
• Sarcomas
• Breast cancer
• Hepatoma

Mutation not detected (Negative for mutation analyzed)
 

Formalin fixed paraffin embedded (FFPE) tumor samples. Microdissection is recommended for better sensitivity and specificity. This would increase the fraction of tumor cells in the sample as it allows capture of the tumor cells. The presence of normal cells that carry wild type alleles can dilute the tumor cells, and dilution by normal and inflammatory cells might impact the sensitivity of mutation detection.

In colorectal cancer DNA can be also isolated from stool samples obtained from patients with colorectal cancer.

In lung cancer, sputum can be used for isolation of DNA from cancer cells.

K-ras Gene Mutation Detection, Cytokeratin 8/18 Low Molecular Weight (CAM 5.2) by IHC (for melanoma), KIT Mutations (for melanoma), NRAS Mutation Detection (for melanoma), Microsatellite Instability/HNPCC by molecular method and by IHC (for colon cancer), Septin 9 (SEPT9) for colon cancer, Methylated DNA Detection by Real-Time PCR (for lung cancer), EGFR by FISH (for lung cancer), EGFR Mutation Detection by molecular method, p53 by molecular method and by IHC, Ki67 by IHC.

7-14 days