Reti said the plan was for the higher screening age to be rolled out within the Parliamentary term - the next three years.
“However, the coalition Government has ambitions to commence as soon as possible.”
National Public Health Service national director Dr Nick Chamberlain said the process could take up to five years.
It was likely to be introduced in stages - raising the age one year each year - beginning with 70 years old.
“The biggest challenge is staff,” he said, noting that another 50 clinical workers were needed to carry out the additional work, including radiologists, technicians and support staff. Recruitment would begin once Cabinet had approved funding, and would take around 18 months.
Reti said the Government wanted to move “as swiftly as possible” but warned the health system needed to be prepared for the 60,000 additional women who would become eligible for screening each year.
“There’s a lot to be done in terms of preparation, both human and capital infrastructure,” he said.
“As well as planning for the expansion of existing screening services, Health New Zealand will need to plan for the cancer treatment services required to support the additional women diagnosed with breast cancer each year.”
Te Whatu Ora Health New Zealand reporting shows that nearly 85 per cent of cancer patients are receiving treatment within the target time of 31 days. This rate had fallen slightly in the past year.
Under the existing system, patients aged between 45 and 69 can get a free mammogram every two years.
Once the screening age is extended, patients will be eligible for two or three additional mammograms.
Reti said early detection meant better treatment outcomes and it was estimated the extended screening age could save 22 lives a year.
Women who participated in the existing programme were 34 per cent less likely to die from breast cancer, he said.
Breast Cancer Foundation chairwoman Justine Smyth said the higher screening age was “absolutely fantastic”. Her organisation had been lobbying for change for “eight long years”.
“We couldn’t be happier that action is finally being taken.”
Smyth said she would now like to see the screening age lowered to 40 years old for at-risk people, in particular Māori and Pacific women.
Asked about the timeframe for implementation, she said: “I’m very happy today that action has started. We are always hopeful that things might happen a bit quicker.”
Te Whatu Ora will also introduce a new register this year which provides new ways to reach screening participants. An estimated 155,000 eligible women who have never been screened will be invited once the register is implemented.
National first announced it would lift the breast cancer screening age in April 2022. Labour also recommitted to the higher screening age during the election campaign last year. The party had previously made it one of its high-priority commitments in its 2017 coalition agreement with NZ First.
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.