There has been a lot of talk lately about the personalized medicine revolution and President Obama's initiative to fund precision medicine. We hear about genetic sequencing and analyzing DNA, but what does all of this mean to a cancer patient?
Sit back while I tell you a little story….
In May of 2013 I was diagnosed with stage 4 non-small cell lung cancer at the age of 37. No idea why. Since it had already spread from my lung throughout my body, surgery was not an option. Cue the devastation, the panic, the shock.
The plan of action was chemotherapy, and while the side effects were far from fun, I was relieved that at least it was working, and my giant tumor (seriously, it wrapped all around my left lung) was shrinking. I could breathe a little easier . . . literally. But a body can only tolerate harsh chemo for so long before the side effects become too damaging to the other organs. So, what do to next? The cancer was smaller, but not gone, and we needed another treatment to keep the cancer from taking over my body.
It was then that we sent a piece of my tumor to be tested for a rare genetic mutation, called ROS1. On Halloween day, I opened my email and saw a note from my oncologist.
Good news, you tested positive for ROS1.
Tears streamed down my face as I read this. "Good news" was quite an understatement.
Now, you may be wondering why I was HAPPY to find out that I had a mutation. Isn't that something out of a horror film? Doesn't that mean my kids will inherit this?
Actually, no. A tumor has its own DNA that is different from that of the person who has cancer. I like to think of it as a parasite living in the host's body. There are some mutations that are passed through generations, but many tumors arise out of random mistakes that happen in regular, everyday cell division.
My cancer is a nasty patch of weeds that has invaded my carefully tended garden.
This pest starts in one spot, and if you don't cut it out of there quickly, it spreads to other places. If it goes unchecked, it will crowd out and suffocate all the flowers and veggies.
If you can't cut it all out (with wide surgical margins), you can try dousing it with industrial strength Weed Killer. This stuff is powerful and often does a great job on the weeds, but as my dad learned after spraying it liberally all over the yard, it does a lot of collateral damage on the others things that you want growing there. We had a polka dotted lawn all summer. (Hi Dad!)
Traditionally, oncologists have used Broccoli Weed Killer on Weeds-of-the-Broccoli, Tomato Weed Killer on Weeds-of-the-Tomatoes, and so on. In recent years, however, scientists have started to take very detailed analyses of these various strains of weeds, and have sometimes been able to find what is driving their growth. The fascinating thing is that at times, Weeds-of-the-Cauliflower turn out to be caused by the same problem as Weeds-of-the-Green-Beans.
With this newfound knowledge, these scientists are in the process of developing a whole new method for eliminating this scourge on your garden. Rather than using Weed Killer, which causes some damage to all of the other plants, they have found that sometimes they can stop these weeds in their tracks by targeting their drive to grow. These targeted medicines whisper to the weeds, "You don't want to grow anymore. Retreat." The rest of the garden goes on blooming happily in the sun while the weeds shrink back.
For me, my twice daily Xalkori has been playing this Jedi mind trick on my cancer for over a year. It is almost certain, however, that one day my cancer will learn to ignore it. At that point, we will take another biopsy to see if we can figure out why my cancer is no longer susceptible to this super drug. At that point, I will try another targeted medicine which I hope speaks the same language as the weeds in my garden.
For me, precision medicine is highly personal, and I am counting on it to extend my life for months and years to come.
Tori Tomalia is many things: a mom, a wife, a theatre artist, a mediocre cook, a Buffy fan, a stinky cheese aficionado. She is also, unfortunately, a repeat visitor to Cancerland. Stay tuned for her continued adventures,