"As a currently incurable Stage IV cancer patient I know that the chemotherapy I am currently taking will not last forever.  My tumors will become resistant.  When they do, absent a successful clinical trial, I will die of cancer in my 40's. I know this but I have not accepted this as inevitable.  I have absolutely no intention of dying in my 40's, not if I have any say in the matter. So it all comes down to clinical trials."

Two weeks ago I wrote those words here on Diagnosis:Cancer.  I had no idea at the time what the next two weeks would bring. Time can move fast in the Stage IV cancer world!

About the time I was writing that column, unexplained pain in my lower back began to appear.  It was an odd pain – nebulous and moving, first on the right, then on the left, sometimes its tendrils even reaching around to the sides. Something in my 44 years I had never felt before.

When you're a Stage IV cancer patient, a few weeks of unexplained pain can't be ignored.  It was strong enough that it was impacting my life, beginning to set up a vicious cycle of pain, low sleep and worry.  These three ingredients combined to make a not very tasty physical and emotional soup.

A CT-scan was quickly ordered, the probable cause of the pain found.  A tumor near my back had grown while I was on chemotherapy.  Operating would be difficult and could also jeopardize my entering another clinical trial.

But the biggest news was that I am now chemotherapy-resistant. I and my new enemy – a group of chemo-resistant tumors – are now staring each other down on either side of the demilitarized zone called my abdomen.

In August, I talked with my doctor about exploring clinical trials because I had no idea if chemotherapy would stop working for me in three months or three years.  As of last Friday, it was indeed in only three months.

Thankfully and miraculously, I had just set up the immunotherapy clinical trial I wrote about two weeks ago.  It is amazing that not only did this opportunity appear, but that I also seized that day.

This is why Stage 4 patients must know about clinical trials before they are needed.  Finding out that your FDA-approved options such as chemotherapy are suddenly more limited is a horrible mental blow.  If I hadn't had a plan of action already in place, I can't imagine how distraught I would be as I scrambled to figure out what could be done.

Instead, what I'm mostly feeling now is excitement that I will be switching over in December to an absolutely cutting edge (albeit experimental and unproven) science to treat my own disease.  That pesky tumor causing all the problems had better be ready… I don't think it has any idea what is about to hit it: 3 trillion virus particles genetically engineered to seek out and destroy Colorectal Cancer.

I like the way that sounds.  A lot.

Dr. Tom Marsilje is a 20-year oncology drug discovery scientist with "currently incurable" stage IV colon cancer. He also writes a personal blog on life at the intersection of being both a cancer patient and researcher "Adventures in Living Terminally Optimistic," a science column for Fight Colorectal Cancer "The Currently Incurable Scientist", and posts science and advocacy updates to Twitter@CurrentIncurSci. This guest column appears on Diagnosis: Cancer through our partnership with Inspire, an Arlington, Va., company with condition-specific online support communities for over 850,000 patients and caregivers.

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