A Capitol Hill communications director who beat cancer three times is gearing up to run the New York City Marathon on Sunday.

Thirty-seven-year-old Kristina Baum, who works in the White House Office of Science and Technology Policy, is no quitter when it comes to a challenge.

She has battled melanoma three times since 2012 and was declared cancer-free on June 17 of this year.

In September, Baum told Beverly Hallberg of the Independent Women’s Forum that when she was diagnosed the first time, it did not seem real.

She commented:

I was about 30 years old when I first found out, and it was a complete shock to me. I do think when you’re first diagnosed, the very first time there is this two to three months period where it just all still feels like a really bad dream, and it feels very surreal. The words, “I have cancer,” are leaving the lips of your mouth just doesn’t even seem like it’s a possibility. It doesn’t seem like a reality to you. It takes a lot of processing to get used to that, unfortunately.

However, Baum was not going down without a fight. Since 2012, she has “covered more than 700 miles by way of one full marathon, 10 half marathons, half a dozen 5Ks and triathlons, and all the miles her pink and turquoise Topo Ultraflys have torn up in between,” according to RollCall.com.

When doctors told Baum in January that she had a brain metastases, or melanoma tumor, she said the right to try different drugs during treatment made a huge difference.

She continued:

I think just having the choice to do it or not is really important. Fortunately, I had the choice, and I chose to do it just as there clearly has to be someone somewhere has to make the choice to want to try. And fortunately, there was a woman many years ago who had late stage melanoma much like me, who made the decision to try. And, fortunately, that woman is still alive and well today, over 15 years later.

Even though she is in remission, Baum noted that the reality that the cancer may return is something she has learned to live with on a daily basis.

She said:

I think one way that I’ve chosen to deal with that fear is just by trusting the Lord and resting in his sovereignty. And that’s been a huge relief and part of how I make it day to day. Sometimes it takes better days than others to recognize that truth, but thankfully God is unchanging even though the circumstances of this world always are, and just moving towards that.

However, Baum is looking forward to joining her fellow athletes at the starting line on Sunday morning.

“You have to dig deep into this file of why you’re doing this in the first place. That’s where you find the reason to keep putting one foot in front of the other,” she concluded.