Support for this educational program provided by Amgen, AstraZeneca, Blueprint Medicines, Bristol Myers Squibb, Genentech, Lilly Oncology, Merck, Novartis and Pfizer.

When tumor tissue is looked at under a microscope, physicians can see what type of cancer it is. But physicians can also look for changes in the DNA of the tumor that might be causing the tumor to grow. Sometimes these changes are called biomarkers or molecular markers.

One way to think about it is that our DNA is like an instruction manual. If there is a typo in the instruction manual, the cell receives wrong instructions and can grow into cancer. Biomarker testing looks for those typos, so physicians know if you are a candidate to receive a targeted therapy that directly addresses those typos.

An error in the ALK gene is one biomarker physicians look for in non-small cell lung cancer. If you have non-small cell lung cancer, it is important to talk to your doctor about comprehensive biomarker testing to see if you have an error in the ALK gene or another biomarker. The results of this testing influence your treatment options. To learn more about biomarker testing, visit

What is an ALK-positive cancer?

ALK stands for anaplastic lymphoma kinase. It was originally described in lymphoma, but most ALK-positive cancers are in non-small cell lung cancer. The ALK gene is in your body when you are an embryo. It helps in the development of the gut and nervous system. It gets turned off while you are still in the womb. For some people, it gets turned back on and fuses (joins) with another gene. This gene change is called an ALK fusion or ALK rearrangement and can cause cancer. When ALK fuses or joins with another gene and causes lung cancer, a patient is said to be ALK-positive.

ALK can fuse with different genes. The most common one is called EML4. Even within EML4, there are different types depending on exactly where ALK fused with the gene. At this point, the recommended course of treatment is the same for most patients who are ALK positive, regardless of the very specific type of ALK rearrangement you may have.

How do you know if you have ALK-positive lung cancer?

To determine if your lung cancer is ALK-positive, you need to test the tumor tissue or your blood. There are several different types of tests that doctors use.

  • FISH analysis: looks at changes in the chromosomes through tissue under a microscope
  • Immunohistochemistry: looks for proteins in the cell under a microscope
  • Next generation sequencing (or comprehensive biomarker testing): tissue from a patient’s tumor (gathered from a biopsy) is placed in a machine that looks for a large number of possible biomarkers at one time
  • Liquid biopsy: looks for tumor DNA in the blood

Your doctor may perform several of these tests at the same time to help confirm results.

Learn more about the different types of biomarker tests here.

Who is most likely to have ALK-positive lung cancer?

ALK-positive lung cancer represents about 4% of lung cancer generally appears in adenocarcinoma non-small cell lung cancer. Patients who are ALK-positive tend to be younger than the average lung cancer patient. They also tend not to have a smoking history.

What are the treatment options for someone with ALK-positive cancer?

Knowing if you have ALK-positive lung cancer has the most treatment implications for stage four patients. Patients with stage four ALK-positive lung cancer will likely be prescribed a pill called a tyrosine kinase inhibitor (TKI) or ALK-inhibitor.


  • Crizotinib (Xalkori)
  • Ceritinib (Zykadia)
  • Alectinib (Alecensa)
  • Brigatinib (Alunbrig)
  • Lorlatinib (Lorbrena)

Within 1-2 years, the cancer is likely to evolve, and the ALK-inhibitor will stop controlling all of the cancer. When this happens, your doctor will try one or a combination of the following options:

  • Another ALK-inhibitor (your doctor may recommend a re-biopsy to determine if a specific ALK- resistance mutation or other changes have occurred that could guide the choice of inhibitor).
  • Increasing the dose of your current ALK-inhibitor
  • Pemetrexed-based chemotherapy (a type of chemotherapy that works particularly well in ALK-positive lung cancers.)
  • Radiation
  • Clinical Trials

Work with your doctor to discuss your goals and options each time you have to make a treatment decision. The three big questions to ask are:

  1. What is the goal of this treatment?
  2. What are the potential side effects?
  3. What other options do I have?

Research is happening at a rapid pace and your doctor should be up to date on the recommendations for your specific type of lung cancer. If you don’t feel comfortable with the answers you are receiving, do not hesitate to seek out a second opinion.

Where can I get support?

Page last updated: June 7, 2024

Freedom From Smoking Clinic
Detroit, MI | May 29, 2024
Asthma Basics Workshop - National
, | Jun 18, 2024