When the principal of a private girls school in North Sydney was told she had lung cancer, the diagnosing doctor asked if she smoked. When she replied that she never had, he said, “Well, you might want to think about taking it up now.”

For Briony Scott, principal of Wenona School, this dark exchange hinted at the mindset that has kept lung cancer – the biggest killer of all cancers in Australia – out of the public eye.