The BRAF mutation affects a small percentage of non-small cell lung cancer (NSCLC) cases, making the cancer more difficult to treat. In recent years, advances in treatment have helped to improve outcomes.

BRAF (V-Raf murine sarcoma viral oncogene homolog B) mutation is an uncommon mutation. Mutated BRAF proteins cause cells to grow out of control. This can affect the lungs, leading to the development of lung cancer.

Advancements in treatment options that target BRAF may improve your chances of survival following a diagnosis of NSCLC with the mutation. You will want to work with your healthcare professionals to determine the best treatment options for you.

BRAF is a type of biomarker for lung cancer. It refers to both a gene and a protein.

In healthy cells, the BRAF protein helps to control or regulate cell growth in the lungs and other areas of the body. It works with another protein, known as MEK, to control cell growth and reproduction.

When a mutation occurs on the BRAF gene, it causes the creation of abnormal BRAF proteins. If you have abnormal BRAF proteins, it may cause an excessive growth of cells in the lungs, leading to lung cancer as the cells start to grow out of control.

The presence of BRAF is a type of lung cancer biomarker. In other words, the presence of BRAF in your blood test could indicate the presence or progression of lung cancer.

The BRAF mutation is a rare mutation. It is only reported in about 3% to 5% of all NSCLC cases. It is found almost exclusively in the adenocarcinoma NSCLC subtype of lung cancer, but it occurs in about 8% of all cancers.

BRAF mutations can also lead to other cancers, such as melanoma or colorectal. There are several types of BRAF mutation that can occur, but the most common type is V600E.

Adenocarcinoma refers to the location where lung cancer starts. In this case, it refers to the outer areas of the lungs in epithelial tissues.

Epithelial tissues, which line cavities and organs, are found throughout the body and help form barriers as well as provide other functions.

Despite occurring almost exclusively in adenocarcinoma, the BRAF mutation only affects about 2% of people with adenocarcinoma NSCLC.

Though anyone can develop BRAF mutations, they are most common in the following groups:

  • females
  • those who have never smoked
  • aggressive histological types of cancer (micropapillary), which are fast growing and spreading

Risk factors for developing NSCLC include:

  • smoking
  • exposure to secondhand smoke
  • exposure to radon, a radioactive gas found in buildings, including homes and places of business
  • exposure to asbestos
  • workplace exposure to different chemicals or substances
  • taking beta-carotene supplements, particularly for those who smoke
  • family or personal history of lung cancer
  • exposure to air pollution
  • previous radiation therapy to the lungs

Though you may not be able to avoid lung cancer from occurring, you can take some steps to help minimize your risk. These include:

  • avoiding radon
  • never smoking or quitting smoking
  • avoiding exposure to pollutants at home or work
  • eating a diet that includes high amounts of fruits and vegetables

Though there are several methods to determine if you have a BRAF mutation, many doctors prefer a comprehensive testing method known as next-generation sequencing (NGS).

NGS uses a sample of lung tissue from a single biopsy to check for different biomarkers, like BRAF, in a single test.

If you are not healthy enough for a biopsy, you may be eligible for a blood test that can check for the biomarker. This may be done if a biopsy might increase your risk for a respiratory complication, such as if you have a diminished lung capacity. If the tumor is small or hard to access, a biopsy might not be the best test.

Diagnosing NSCLC often involves several tests. These can include:

  • X-rays
  • biopsies
  • MRI
  • CT scan

If you have BRAF-positive NSCLC, you will likely receive targeted treatment medications. These medications specifically stop cancer cell growth by targeting the errors in the BRAF and MEK genes.

The medications used include dabrafenib (Taflinar) plus trametinib (Mekinist) or encorafenib (Braftovi) plus binimetinib (Mektovi).

If the cancer continues to grow following first-line treatment, an oncologist may try immunotherapy with or without chemotherapy.

If you have a different type of BRAF mutation (non-V600E), an oncologist will likely start with immunotherapy with or without chemotherapy because the first-line medications will not be effective.

All treatments have a risk of side effects. You should discuss your treatment goals, side effects, and other options.

For example, you may qualify for a clinical trial for treating BRAF NSCLC. Clinical trials help researchers test new treatments to determine their safety and effectiveness.

According to one review, the outlook effect of the BRAF mutation is unclear. Some smaller studies have shown that the presence of a BRAF mutation may help increase the survival time associated with NSCLC.

But they also note that in order to better understand how BRAF affects outlook, larger studies are needed.

The BRAF mutation refers to a change in the BRAF gene. The change causes the BRAF protein to function abnormally. This can lead to excessive growth and reproduction of cells in the lung or other areas of the body.

If you have NSCLC, part of the testing process will help determine if you have any biomarkers, such as BRAF. It is unclear how a BRAF mutation affects survival rates, but some evidence from smaller studies suggests that it may help increase survival length.