Gene mutations in lung cancer (for the beginner)

If you have non-small-cell lung cancer, some of the most powerful information you can have is about gene mutations and their role in lung cancer treatment. With an up-to-date knowledge of gene mutations, you and your doctors may be able to manage a great quality of life for a substantial period of time, even if your cancer is advanced and incurable.

Basically, cancer happens when something in the genes or DNA of your cells goes haywire. The mechanisms that control the division and multiplication of cells get fouled up, resulting in an uncontrolled proliferation of cells. Unlike an infection, which is a foreign organism invading your body, cancer is your own body – your own cells – gone wrong.

Scientists are now able to look at the genes of cancer cells and, in more and more cases, see exactly what has gone wrong. They can see where the molecules have been rearranged so that the genes can’t do their job anymore. It’s almost like computer programmers finding the tiny bug – the line of scrambled code – that causes a whole system to crash.

Some genetic mutations (the lines of scrambled code) have a physical shape that makes it possible to target them with medicine. Some of the newest cancer drugs are designed to shut down particular genetic mutations by binding to them. Imagine a unique key sliding into a keyhole and turning a lock, only at a microscopic level.

Lung cancer is caused by different genetic mutations. You and I may have the same symptoms, but precisely what is out of kilter in your DNA may be different from what is out of kilter in mine. There are many microscopic locks, and not all of them have been discovered yet. To some of the locks, however, oncology now has keys.

The three most common known gene mutations in non-small-cell lung cancer are EFGR (epidermal growth factor receptor), ALK (anaplastic lymphoma kinase), and KRAS (Kirsten RNA Associated Rat Sarcoma 2 Virus Gene). There are other less common ones, such as ROS1, which I have. Many remain unknown.

For EFGR and ALK, there are targeted medicines on the market now, and they are more effective against cancer with those mutations than standard chemotherapy. They are oral medicines (no being hooked up to a chemotherapy pump all day). You may hear about Tarceva (generic name erlotinib), which targets the EFGR mutation, or Xalkori (generic name crizotinib) which targets ALK. ROS1 is a rare mutation and does not yet have medicines specifically developed for it, but we are fortunate that ROS1 cancer can also respond well to Xalkori/crizotinib. This is why I’m doing so well right now: we finally figured out that I have the ROS1 mutation, and I am thriving on crizotinib.

Unfortunately, these medicines do not work forever. Eventually the cancer mutates again and figures out how to outsmart them. I am told that the average patient who responds well to crizotinib gets a little less than a year of great health from it, and then it stops working. I’ve already had four months of great health. However, scientists and doctors are already working on ways to get around this resistance, and they are making progress.

This is why you need to see a specialized thoracic oncologist, especially if your cancer is advanced. It’s also why you may want to ask your doctors to take extra tissue for testing, even if you are having a biopsy at a community hospital. This aspect of lung cancer treatment is very new, and not all oncologists are even up to speed. I’ve read stories of lung cancer patients being sent to hospice because their doctors thought there was nothing else they could do, and then recovering dramatically, though not permanently, on genetically targeted medicine. If you have advanced non-small-cell lung cancer and your doctors have not discussed genetic testing with you at all, find new doctors.

About Irene Elizabeth (Beth!) Stroud

Queer suburban mom, graduate student, lung cancer survivor, card-carrying United Methodist.
This entry was posted in Uncategorized and tagged , , . Bookmark the permalink.

3 Responses to Gene mutations in lung cancer (for the beginner)

  1. Arrin Crain says:

    Irene, this is awesome that you’re sharing this valuable information. You’re right, I think one of the key elements is realizing that your first oncologist might be able to prescribe Tarceva or Xalkori – depending on your mutation of course – but don’t stop there. It was a hard realization this December, that even though my mom’s onc is a nice guy he offers standard (emphasis on standard) care. I have been making notes about LDK378 and so many other clinical trials but he was never going to offer them after Xalkori. We are now going to visit an ALK specialist who can provide us with more targeted drugs and thus more hope.

    Best wishes to you!
    Arrin

  2. Renee' says:

    Hi, is it Irene? I stumbled on your blog by one of your bloggers leaving a message on Inspire. I kind of have set up temporary camp over there. I thought of a blog and I may, eventually—if I get put in Inspire jail again…(-: Anyway, nice job you have done here. Truthfully, the best I have seen, Irene. The most complete and I like the fact that you have jumped right on the mutation topic. It needs to be explored a little more. You stopped a little soon. There is more going on than what you mentioned. Squamous do have mutations. I am here to save Dave. Davstar is my Inspire name. I am not Dav’s star…Star is part of my maiden name…(-: Just wanted to clarify that. You are very knowledgeable. I am hopeful mutation testing is going to save a lot of lives. Foundation Medicine is doing a lot of good work. Check them out if you haven’t already. Okay–I’ll be back. Great job! I think maybe you are a Star! (-:

    • istroud says:

      Renée, my name is Irene Elizabeth, but most people call me Beth. Thank you for your kind words! I definitely want to come back to the mutation topic later on. Right now I’m just trying to remember what information I could have handled and used in the first six weeks or so after diagnosis. Are there articles you would recommend about mutations in squamous cell cancer? If you hover over my picture in the sidebar, you should see my Gravatar card with my email address in the upper right corner.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s