After Graeme Wall received an invitation in the mail to test for bowel cancer, he left the testing kit on the dinner table for six weeks.
The dairy farmer, from Ōtorohanga, felt no urgency. Aged 62, he had no family history of cancer, no risk factors, and no symptoms. He was fit and healthy and got up each morning around 6am to work in the milking sheds on his 115-hectare farm.
As the testing kit gathered dust on the table, a tiny cancerous lump was growing inside his bowel.
In May, he eventually decided to send off a stool sample, which came back positive. A colonoscopy confirmed his cancer diagnosis. It was a shock to his partner Bridget and his two children.
“Whenever you hear the word cancer you always think the worst,” he told the Herald.
But because it was caught early, it had not spread. Wall was able to avoid intensive treatment like chemotherapy and - with the help of private health insurance - get curative surgery around a month after his diagnosis. He is now in remission.
“I’m extremely grateful for the screening,” he said. “I wouldn’t have noticed anything otherwise because I just felt like normal me. No signs of anything. Just out of the blue.”
Wall’s cancer was one of more than 2000 cases picked up by the national screening programme since it was rolled out in 2017.
Out of concern about resourcing, the scheme was limited to 60-74 year-olds at the time, despite most countries starting at age 50. The eligibility age is gradually being lowered for Māori and Pacific people, because they develop bowel cancer earlier.
A growing chorus of voices now says the screening age should be lowered across the board, and possibly lower than 50. Proponents of a lower age cite the success of the existing scheme and evidence that the disease is increasingly affecting younger people.
The national scheme was introduced in 2017 after a trial within the former Waitematā District Health Board.
The first study to look at the outcomes of the Waitematā scheme has just been published, and its co-authors said its findings strengthened the case for a lower age.
The study, published in the ANZ Journal of Surgery, compared the outcomes of patients who were diagnosed with colorectal cancer through the screening programme with patients who were diagnosed outside the programme.
Screened patients were more likely to have early-stage cancers, which were potentially curable. They also had far fewer Stage 4 cancers.
Patients whose cancers were picked up in screening also had a 50 per cent lower chance of dying in the period covered by the study - even when adjusted for age and the stage of their cancer.
“If you have a bowel cancer and you can get it diagnosed through the screening programme, you are going to do a hell of a lot better,” said Dr Jesse Fischer, a colorectal surgeon at Waikato Hospital and co-author of the study.
Fischer, a Royal Australasian College of Surgeons Fellow, said the study underlined the importance of getting more eligible people to participate in screening. He also said that there was “indisputable evidence” that lowering the screening age to 50 years old would save lives and be cost-effective.
“It’s a no-brainer,” said Fischer. “Everyone in the world is doing it and we should too.”
A New Zealand Medical Journal editorial this month proposed an even lower screening age, suggesting that it should be set at 45 years old overall and 40 years old for Māori and Pacific people.
“This is particularly important for Māori, as 30 per cent of bowel cancer in Māori females and 25 per cent in Māori males occurs before age 50,” the editorial said.
It highlighted that bowel cancer was increasingly a young person’s disease, with incidence rates for under-50s rising in New Zealand and overseas.
Comedian Dai Henwood - who has become the public face of bowel cancer in New Zealand after his Stage 4 diagnosis this year - found out he was positive at age 43.
The Waitematā pilot programme had an age bracket of 50 to 74 years old but this was raised to 60 for the national service because officials were worried about capacity constraints.
Dr Frank Frizelle, colorectal surgeon and NZMJ editor-in-chief, said he believed it would be possible to lower the age without swamping the system. While around 8 per cent of people screened in the existing scheme were referred for a colonoscopy, the rate would be lower in the 50-59 bracket.
“There is still an increase in need, but all you are doing is moving the goalposts and dealing with stuff that is going to turn up on your doorstep later - especially with the change in demographics.”
Demand could also be managed by having an opt-in system for younger people - as in Australia - or by not requiring all younger people to have a full colonoscopy - instead offering them a more minor procedure.
Asked whether she backed a lower screening age, Health Minister Ayesha Verrall said Te Whatu Ora’s primary focus was on improving delivery of the existing service to increase participation.
Around 58 per cent of people who receive the testing kits send them back, which is relatively high by international standards. However, the higher-risk groups - Māori and Pacific - have lower participation rates, with the Pacific rate especially low at 39 per cent.
Verrall said Te Whatu Ora continued to review the benefits and resources required for further changes to the programme, including expanding its eligibility - especially to address health inequity.
However, she appeared to rule out an eligibility age as low as 45, saying that official advice showed no comparable country was screening people between 45 and 49. Australia allows this age group to request a free test, but they are not invited to take part.
Too high? The changing age of bowel cancer screening
2011-2017: Pilot scheme in Waitemata DHB, covering 50-74 year-olds
2017-2021: Screening rolled out nationwide, but minimum age raised to 60
November 2022: Age lowered to 50 for Māori and Pacific in Waikato
Late 2023: Age to be lowered for Māori and Pacific in Tairawhiti and MidCentral
Mid-2024: All Māori and Pacific aged 50+ will be eligible
Isaac Davison is an Auckland-based reporter who covers health issues. He joined the Herald in 2008 and has previously covered the environment, politics, and social issues.