Two weeks after relocating, the fit 39-year-old headed out for an uphill jog and found herself “completely out of breath. I had to start walking and thought this is so strange.” She figured it must be a bout of walking pneumonia, a mild form of the lung infection, and carried on with her weekend.

“We didn’t even have a doctor yet, so that Monday morning I went into a walk-in clinic and asked if they had X-ray capabilities,” she says, still thinking pneumonia was making it hard to breathe. The diagnosis that came days later was one she never expected: stage 4 lung cancer.

At the walk-in clinic, Nerstad was told she might have a collapsed lung and needed to go to an emergency room right away. In the ER, doctors determined she had fluid on her left side, but “we had to figure out why,” Nerstad says. After a number of tests over four days in the hospital, she was discharged. “They told me they thought I had ovarian cancer and that I would need to follow up with another doctor.”

Hearing the word “cancer” was understandably upsetting. “We left with more questions than answers,” Nerstad says. “Cancer doesn’t run in my family at all—I was completely shocked.” The next day she brought all her paperwork from her first hospital stay to a second emergency room, where she had more testing. After “six or seven days,” she says, of “a lot of tests to rule out everything,” she ended up in a video-assisted surgical procedure that uncovered the real cause of her symptoms: lung cancer.

While she was in surgery, her doctor broke the news to her family. When she woke up, she found herself in a new reality. “My family was all around me in my hospital room. I could tell everyone was very visibly upset. I was kind of groggy, but I remember saying, ‘What’s going on, what did you find out?’”

Her doctor filled her in as a new wave of shock came over her. “Cancer was the furthest thing from my mind, but lung cancer, I just couldn’t believe it.” She was only 39, she wasn’t a smoker, she ate healthy, ran, and did yoga. Even worse were those ominous words: stage 4. “I was very concerned with my time left.”

She wasn’t supposed to have much of it, anywhere from two weeks to nine months, according to her surgeon. But a hunch from her oncologist changed everything.

He wanted to run genetic testing, something he felt could be a “game changer,” Nerstad remembers. It would take 10 to 14 days to get the results back, he warned her—which could possibly be all she had left to live, she recalled her surgeon telling her. But it could shift her treatment plan and prognosis entirely.

So she went for it. “It was the longest 10 to 14 days waiting for this genetic testing and still not really understanding all of it,” Nerstad says. When her doctor finally called, it was with good news, at least in terms of a stage 4 lung cancer diagnosis. She had a type of lung cancer called ALK-positive, which is caused by a specific genetic mutation that could be treated with targeted therapy instead of traditional chemo.

She started a personalized treatment plan taking alectinib, a twice-daily oral targeted therapy that prevents the cancer from spreading. That was two years ago. “It’s keeping me alive,” says Nerstad, now 41, with awe in her voice. “My two weeks to nine months have turned into over two years, and I’m doing great.”

The side effects include foot and muscle pain that usually goes away “pretty quickly once I get up and moving,” fatigue, and sun sensitivity. But they’re minimal. “It’s not worth complaining about,” she says. Instead, she’s glad she’s been able to return to something close to her pre-cancer life, enjoying time with her family and getting back to exercising.

Treatment will be lifelong, but eventually, Nerstad knows she’ll grow resistant to the pill. People with ALK-positive lung cancer almost always develop resistance to treatment; a 2018 article in Current Oncology described this unfortunate side effect as an “inevitable development.” The reason why isn’t totally understood, but it’s thought resistance could be fueled by a strengthening of the existing genetic mutation or additional mutations.

That’s why raising money to fund lung cancer research is her focus now. “It’s so important to continue research and funding for more targeted therapy pills so there will be more options when I gain resistance,” Nerstad says.

Her daughters have taken up the charge alongside her. Every year, they’d make a bucket list of activities to do over the summer. A lemonade stand got on the list after Nerstad was diagnosed, and one of her daughters, just 7 at the time, suggested the proceeds go to a worthy cause. “I’m thinking she’s going to say an animal shelter, but instead she was like, ‘What about lung cancer?’”

Friends and family turned up to the stand, and even the local news came by. By the end of the day, they’d raised over $5,000. Last month they threw another family fundraiser, this time with face painting and a bounce house, raising almost $23,000 for ALK-positive research, Nerstad says proudly.

“I live my life just like I used to. The only thing that really changed is the way we look at life,” she says, thankful for each day she has.

She uses her diagnosis as a teachable moment. “You are your best advocate,” she says. “Looking back, I had acid reflux maybe six months before that. Maybe that was a sign.” Today, she’s quick to make a medical appointment when something doesn’t feel right, for herself or her girls.

And of course, she’s constantly rebuffing the biggest misconception about lung cancer: No, it isn’t only a smoker’s disease. “I’m the perfect example that anyone with lungs can get lung cancer.”