Cancer Society Medical Director Chris Jackson said putting these machines in the regions means more people will get better access to treatment closer to their home and families.
"While infrastructure is only one part of the cancer programme, it's great to see the machines going where they are needed the most. These will reduce wait times and improve outcomes for people needing treatment."
Ardern today said this was one of the most significant investments in cancer care that has been seen in New Zealand in some time.
And she said more cancer action from the Government was coming later this month when it announces its Interim Cancer Action plan.
However, neither Ardern nor Health Minister David Clark would say what would be in the plan.
Asked if a national cancer agency would be part of the next announcement, Clark wouldn't say.
In Opposition, Labour promised to spend $20 million to set such an agency up.
Last week, National promised that if it wins 2020 election it will fund the agency.
Today, its Leader Simon Bridges said the Government's announcement was a desperate attempt to look like it's doing something while it continues to have no plan.
"This will be bitterly disappointing for thousands of cancer sufferers who would have been expecting a lot more today.
"This is little more than business as usual that any government has to do, replacing machines that need replacing."
Lung Foundation Chief Executive Philip Hope said although today's news was encouraging, he would have liked to see Tairawhiti get a new machine.
He said he was patiently waiting to see what additional resourcing needs will be provided when the Government unveils its cancer action plan next month.
Patient Voice Aotearoa chairman Malcolm Mulholland wants the Government to put a lot more money towards funding cancer drugs as part of its cancer action plan.
"I want them to announce a reform of Pharmac and a doubling of the Pharmac budget."