Tauranga Labour list MP Jan Tinetti has been diagnosed with breast cancer after a regular mammogram showed irregular calcifications.
In a Facebook post, she said she is taking "a few weeks" to rest and recuperate.
She was told after a couple of biopsies that her best option was to operate. She had been staying at Grace Hospital following this.
Tinetti went home on Tuesday.
She apologised for having to cancel a number of her appointments, but said she's tried to keep her commitments where she's been able to.
She thanked Prime Minister Jacinda Ardern and her colleagues for being "incredibly supportive". She also thanked her "amazing" medical team.
"Thanks to everyone for your love and support and your understanding that I need to take the next few weeks to regain my full health again," she said.
Tinetti told the Bay of Plenty Times she will still be campaigning in the 2020 election.
"I intend to get right back into the swing of things for the campaign next year. My recovery will take probably six weeks.
"I have the full support of our fantastic Prime Minister to take some time out now. I'll be taking the summer and I intend to get back into things, at this stage, as long as my recovery goes well, at the end of January," she told the Bay of Plenty Times.
She said there was no lump, and her diagnosis shows the importance of getting regular mammograms.
Tinetti was elected in the 2017 election as Tauranga's list MP. She is currently the deputy chairperson of the Education and Workforce Select Committee.