Like most people, Christal Parkinson thought lung cancer was a disease only smokers had to worry about.
But at 24, three months after she married, she was stunned to be diagnosed with an advanced stage of the disease.
Doctors initially thought she had pneumonia when she complained of a persistent cough four years ago.
Even when a chest X-ray revealed a shadow, no one could believe she had lung cancer because of her age.
But pathology tests after surgery to remove one of the upper lobes of her lungs confirmed the worst - stage four disease which would need three months of high-dose chemotherapy.
"I was pretty angry when I first found out because I had never smoked, so I wondered how it could happen to me," she said.
"I was told my chances of having kids were pretty slim after the chemo, which was another blow."
Now 28, Mrs Parkinson and her husband Stephen have living proof that doctors are not always right as doting parents of daughters Hailee, 22 months, and Courtney, eight months.
So far, tests show she is clear of cancer but there are few days when she does not worry about it.
The Australian Lung Foundation, the Lung Cancer Alliance, the WA Health Department and Cancer Council WA are holding Shine a Light on Lung Cancer, a vigil on Saturday from 6.45pm at the Perth Cultural Centre to raise awareness and hope.
WA Cancer Registry figures show there were 577 new cases of lung cancer in men and 393 in women in 2010.
Sir Charles Gairdner Hospital respiratory physician Martin Phillips said though most people with lung cancer had smoked - many taking up the habit before the true risks were understood - a third of women with lung cancer had never smoked.
Although breast cancer was far more common in women, lung cancer was their biggest killer.
But if doctors understood more about the sub-types of lung cancer, they could tailor treatment more effectively.
See www.lungfoundation.com . au/shinealightonlungcancer.