Writing in today’s journal, Otago University professor David Skegg said if the Australian death rates applied in this country, 616 fewer New Zealand women would have died a year and 215 fewer men.
Professor Skegg said most of the “excess” deaths in New Zealand compared to Australia were in people under 70 years old. He said the higher death rate from all cancers combined cannot be attributed to higher incidence rates of cancer, and this suggests that overall patient survival is lower in New Zealand.
Researchers say colorectal, or bowel cancer (for both sexes), lung and breast cancer (both for females rather than males) make up most of the difference in outcomes.
Between 2000 and 2007, deaths from bowel cancer were 35 percent higher than in Australia for women and 24 percent higher for men.
Lung cancer deaths in women were 20 percent higher in New Zealand compared with Australia over this period, while deaths in men were about the same as Australia, although the incidence of lung cancer among men in New Zealand is 10 percent lower than in Australia.
One of the studies says this suggests that clinical survival rates are lower in both sexes. Researchers say the main problem is smoking among Maori women in particular, who may also be worse than males at seeing a doctor early with symptoms.
Deaths from breast cancer were 19 percent higher in New Zealand than Australia between 2000 and 2007. Both countries have screening programmes, and the studies say in New Zealand it’s estimated deaths decreased by as much as 40 percent for those being screened.
But the researchers say treatment differences could also have played a role, with the anti-cancer drug Herceptin available in Australia for longer than it has been in New Zealand, where it was funded from 2008.
They also say there were substantial delays in the past to many women beginning radiation therapy in New Zealand, with significant numbers of women going to Australia for treatment.
Overall, the authors say the mortality gap may be due to lifestyle and ethnic differences , and partly due to New Zealanders presenting with more advanced cancers, along with less easy access to some treatments.
An author of one of the studies, the former medical director of the Cancer Society, Peter Dady, says there’s been a lack of progress over national screening for bowel cancer and it’s a disgrace. “They’ve been dragging the chain forever on this and in the meanwhile, people are dying. And that I think is appalling.”
He says national screening for bowel cancer in Australia means it’s detected at an earlier stage, treated earlier and people have a better chance of surviving.
Dr Dady says introducing national screening in this country is a “no-brainer”.
“What should happen is that the Ministry [of health] should say, Well it looks as if bowel cancer screening is coming and OK we’re going to have to increase the number of colonoscopies. Put some money out there saying there’s x number of bucks for a colonoscopy, public system, private system, do it. How are you going to do it? Do you want the money? They generally do.”
Another author, Wellington-based Otago University cancer specialist David Lamb, says he was “very very disappointed” to see death rates had not decreased across the Tasman.
“What is disappointing is really that we knew the main areas where there were deficiencies in New Zealand 10 years ago and yet … particularly in the area of colorectal cancer, we’ve made so little progress in turning it around.”