READ MORE
• Cancer: Are poor being sent home to die?
• Lung cancer treatment 'frustrating'
• Richard's story: Trial offers light in tunnel
• Chris Atkinson: Lung cancer lacks profile of other cancers
• Foundation to fight for lung cancer
Now 50, the married father of two boys at first thought he had caught a virus doing the rounds in September 2012 at Otago University, where he is a pharmacology lecturer.
When the cough hadn't gone by the summer, he saw a GP who changed his blood-pressure medication and tried him on asthma inhalers, to little effect. Several months later Dr Ashton, a runner, found he was out of breath and had pains in his arm and chest.
A cardiologist ran tests, including a chest X-ray. It was the abnormal lung nodules shown on that image which led to a CT scan, then a lung tissue sample and a diagnosis of lung cancer in July 2013.
Two different regimens of chemotherapy followed. Neither produced any improvement.
In late 2013, Dr Ashton saw a Reader's Digest item about clinical trials in Australia. He contacted the researcher, who said that although he was not eligible for the trial, he should consider testing for gene mutations for which new treatments were emerging.
"I had a colleague in Auckland, an oncologist, Mark McKeage ... working on this. He had a small study going testing various [kinds] of lung cancer for different mutations - EGFR and ALK [epidermal growth factor receptor and anaplastic lymphoma kinase] and others. I enrolled in that."
Dr Ashton was positive for the ALK mutation and managed to get on to a drug company's compassionate programme for crizotinib, not then registered in New Zealand.
"Within nine days the coughing had stopped. ... After two months I was jogging for 50 minutes ..." CT scans showed the abnormalities were rapidly resolving.
"There were dozens if not hundreds of nodules. They are gone. It's clear. I'm in remission."
The Series
Monday: Breast Cancer
Yesterday: Bowel Cancer
Today: Lung Cancer
Thursday: Melanoma
Friday: Prostate Cancer