Lung Cancer Biomarker Testing

Every person’s cancer has a unique set of biomarkers. Biomarkers are proteins, hormones, or DNA segments that can assist in the diagnosis and treatment of lung cancer and other conditions based on it’s abnormality. Cancer cells and your body release biomarkers in response to invasions of cancer in the body. Biomarkers play a significant role in the diagnostic process as healthcare professionals now have biomarker testing for lung cancer. Today, your medical team can test for biomarkers in your blood, urine, tissues, and other bodily fluids. After receiving a diagnosis, your team can achieve better-targeted treatment based on your specific biomarkers.

Lung cancer biomarkers continue to drastically change the way doctors determine diagnosis and treatment. As scientists learn more about biomarkers and their meanings, they will be able to diagnose patients more quickly and efficiently as well as produce and match treatments more effectively. Learn more about the biomarkers specific to lung cancer and how biomarkers can influence your next lung cancer screening or medical update.

What Are the Biomarkers of Lung Cancer?

Lung cancer is broken into two subtypes: small cell and non-small cell lung cancer. Small cell and non-small cell lung cancer are similar but differ in size and how they metastasize. Additionally, there are two primary types of lung cancer biomarkers: mutation and immune response biomarkers. Mutation biomarkers are gene modifications that promote the growth of cancer cells such as the tumor protein p53 which is a common mutation found in NSCLC patients. Immune response biomarkers predict how well your cancer will respond to immunotherapy. A common NSCLC immune response biomarker is the programmed cell death protein, located on healthy white blood cells and stops your immune system from attacking cancer.

Does Non-Small Cell Lung Cancer Have Biomarkers?

Non-small cell lung cancer (NSCLC) is the most common form of lung cancer in the US, making up 84 percent of all cases. NSCLC has three subtypes: adenocarcinoma, large cell carcinoma, and squamous cell carcinoma. Adenocarcinoma is a type of cancer that typically develops in mucus-producing cells and accounts for 40 percent of all NSCLC diagnoses. On the other hand, squamous cells represent 25 percent of diagnoses and develop in the lining of the bronchi. Additionally, large cell carcinoma accounts for 15 percent of NSCLC diagnoses and can occur anywhere in the lungs. There are several gene mutation biomarkers for non-small cell lung cancer including:

  • Tumor protein p53 (TP53)
  • KRAS
  • Epidermal growth factor receptor (EGFR)
  • Anaplastic lymphoma kinase (ALK)
  • Mesenchymal-epithelial transition (MET) and MET exon 14 (METex14)
  • Phosphatidylinositol-4-5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA)
  • BRAF V6OOE
  • Human epidermal growth factor receptor 2 (HER2)
  • ROS1
  • RET
  • Neurotrophic tyrosine receptor kinase (NTRK)
  • NRAS

There are also immune response biomarkers for NSCLC such as:

  • Programmed cell death protein (PD-1) and programmed cell death ligand 1 (PD-L1)
  • Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4)

Does Small Cell Lung Cancer Have Biomarkers?

Small cell lung cancer (SCLC) is the other subtype of lung cancer but differs from NSCLC as it is smaller and metastasizes more quickly and aggressively. Biomarkers do exist for small cell lung cancer, however, medical professionals primarily utilize biomarkers in the diagnosis and treatment of non-small cell lung cancer. However, there are biomarkers on the horizon for SCLC such as retinoblastoma (Rb). The Rb protein is associated with intense aggressiveness and resistance to typical treatments. If Rb and other biological molecules are discovered to be a biomarker for SCLC, doctors can target therapies to better treat patients and their unique stage of lung cancer.

How Biomarkers Are Identified

Biomarker testing is different than conventional genetic testing which is used to find inherited cancer mutations. Instead of finding those inherited, like in genetic testing, biomarker testing aims to find specific genes that developed as a result of cancer. If you are experiencing symptoms of lung cancer, a doctor may take a urine, blood, stool, or bodily fluid sample, which they can search for a cancer biomarker. Additionally, if there is a solid tumor, doctors may choose to do a biopsy of the tumor to collect a sample of cancer cells.

There are several different types of biomarker tests as some search for a single biomarker while others look for biomarkers found in many cancer types such as mesothelioma. Common biomarkers tests include:

  • Whole-exome sequences – all the exons in a genome
  • Whole-genome sequences – all the DNA from a genome
  • Liquid biomarkers – all the DNA and cells from a sample of blood

Once a doctor collects a sample, they send the cells to a laboratory where scientists will test for particular biomarkers. The team at the lab will provide results listing which biomarkers are in the cancer cells. With these results, you can collaborate with your medical professionals and caregiver to determine the best treatments that work for your cancer and biomarkers. Biomarkers can be particularly instrumental in treatments such as targeted therapy and immunotherapy that target specific biomarkers.

Predictive vs Prognostic Biomarker

Prognostic biomarkers present doctors and their patients with information about which cancer outcomes are likely or unlikely to occur. On the other hand, a predictive biomarker provides information about treatments and their benefits. Predictive biomarkers go hand in hand with personalized (precision) medicine, as doctors can tailor a patient’s treatment plan. Precision medicine utilizes biomarker tests to select the lung cancer treatments most likely to work while sparing patients from unhelpful treatments.

Why Biomarkers are Important to Lung Cancer

As scientists continue to learn more about biomarkers, patients will receive faster, more accurate diagnoses and receive targeted treatment plans for lung cancer and lung diseases like mesothelioma. Lung Cancer Center can answer your questions about biomarkers and connect you to diagnostic and treatment centers. Get your free lung cancer guide to learn more about biomarkers and their impact on your lung cancer journey.