Quick Facts:
- Once you have a lung cancer diagnosis, molecular testing can help determine personalized care.
- Molecular testing involves detecting specific molecules in cancer cells.
- It usually involves sending biopsy tissue and blood draws to a laboratory for testing.
- Molecular testing is now standard for lung cancer workup and is generally covered by insurance, but coverage may vary.
One of the ways your team will help ensure that you get the right treatment is with molecular testing. This is an advanced way of looking at your cancer that can help improve your outcome and quality of life.
Read MoreWhat is molecular testing?
Lung cancer is the second most common cancer in the United States, with an estimated 240,000 new cases diagnosed every year. But not every lung cancer is the same. Molecular testing helps map your specific cancer by searching for specific genetic changes that are causing the cancer cells to grow and spread. These changes are called biomarkers or mutations, and they can vary from person to person.By testing a sample of the tumor tissue or your blood, doctors can identify the biomarkers that are present in your lung cancer. Based on what they find, they can recommend the best treatment options, including targeted therapies that attack the cancer cells with the specific biomarkers.
Molecular testing can also help monitor the response to treatment and pick up any signs of the cancer coming back.
Doctors usually recommend molecular testing for people with advanced lung cancer, especially non-small cell lung cancer (NSCLC).
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How is molecular testing performed?
The molecular testing process starts when your doctor takes a sample of your tumor. This is called a biopsy.
You may receive a tissue biopsy, where the doctor removes a small piece of the tumor, or a liquid biopsy which is done by taking blood. Sometimes you will have both types of biopsies.
Next, your doctor will send your samples to a laboratory for molecular testing.
The laboratory uses special techniques to analyze the genetic material in the sample, such as DNA or RNA. These techniques can make the genetic material more visible and pick up on any changes or mutations.
There are two main types of molecular testing techniques:
- PCR amplifies and detects DNA or RNA in a sample.
- Sequencing reads the structure of the DNA or RNA sequence and compare it with a normal or reference sequence.
Both techniques can show the type and subtype of the cancer, its stage and the aggressiveness of the disease. They can also find the presence of any biomarkers or mutations.
Test results help guide treatment and monitor disease. They also help you and your doctor decide on the best course of action, such as surgery, chemotherapy, radiation, or targeted therapy.
One thing to keep in mind about testing is that it takes time.
“[After] testing, it takes two, three weeks to get the results,” Dr. Mohamed Mohamed, a thoracic medical oncologist at Cone Health Cancer Center at Greensboro, tells SurvivorNet.
Dr. Mohamed says he orders molecular testing from the get-go, as soon as his patient get their initial biopsies. This helps cut down on any delays that can slow down crucial treatment decision-making.
“So, by the time I see the patient… after the biopsy, I have some [molecular testing] information to make the decision for these patients,” he says.
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Why you may have both a tissue and blood biopsy
A liquid biopsy is a blood test that can detect signs of cancer tumors in the bloodstream.
Some pros and cons:
- Liquid biopsy is less invasive, faster, and cheaper than a tissue biopsy.
- It can look at more than one location at once.
- It’s easy to repeat which is useful to monitor treatment and track the cancer.
- However, a liquid biopsy is not as sensitive as a tissue biopsy, meaning it may miss some cancer.
- It may also return false results.
A tissue biopsy is a procedure that removes a sample of tissue from the lung for examination.
Some pros and cons:
- It can confirm the presence and type of lung cancer to help determine the best treatment options.
- It can detect other health problems.
- However, a tissue biopsy is more invasive, risky, and costly. It may not get enough tissue for an accurate result.
- It may cause complications such as bleeding, infection, or lung collapse so it may not be safe for some advanced or metastatic cancer patients.
- It also may not capture complete information,
- And, it can’t be repeated as often as liquid biopsy so it may not catch the changes over time or during treatment.
When taken together, the two types of biopsy help get a more complete picture of your cancer. They provide valuable information about the genetics and characteristics of lung cancer, which can help guide treatment decisions.
Does insurance cover molecular testing?
Most insurance covers molecular testing because it is now a standard part of the workup for lung cancers.
However, insurance providers differ. It’s best to check with your doctors to see what is — and is not — covered.
Dr. Mohamed says your doctors should communicate with testing companies to help you avoid any unexpected out-of-pocket costs.
“Testing companies [have reassured us] that [they will] reach out to the patient if the cost for [their testing] will be more than a hundred dollars before the tests are run,“ he says.
Still, if you aren’t covered, the cost of molecular testing can run $6000 or more.
Questions to Ask Your Doctor
Understanding more about molecular testing can help you feel more comfortable about the process. Some questions you may want to ask your doctor:
- Has my lung cancer biopsy tissue been sent for molecular testing?
- Do I need a liquid biopsy to ensure complete and accurate molecular testing without delays?
- What do the results of my molecular testing show?
- Based on those results, what are my treatment options?
- Will you have to repeat any of the tests?
- What does my insurance cover?
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