UNDATED (NBC)–Samantha Mixon looks and feels great, but she is fighting stage four lung cancer and all the assumptions that people make about her disease.

“The first thing they ask is, ‘Did you smoke?’ It’s annoying at this point,” Mixon said.

She’s a non-smoker with no family history and only 33 years old.

She was diagnosed in November at Piedmont Henry Hospital after complaining of migraines. Turns out, she had a tumor that formed when the lung cancer metastasized to the brain.

“Telling my daughter was the hardest part about it,” Mixon said. “How do you tell her your mommy’s odds are not very good for five years, it’s one of the hardest things I’ve ever had to do.”

Mixon is part of a troubling trend, according to Piedmont Atlanta thoracic surgeon Dr. Saeid Khansarinia.

“We’re seeing more and more lung cancer in people who don’t smoke, especially women,” Dr. Khansarinia said.

Dr. Khansarinia said no one really knows why, but he said new targeted chemotherapy drugs are working well for younger, nonsmoking women.

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