The number of claims ACC is accepting for cancer misdiagnosis has almost doubled in five years.
It's sparking calls for better access to life-saving cancer testing - especially for younger people.
Jo Mckenzie-Mclean is cherishing every moment she has with her kids after being diagnosed in January with stage four bowel cancer that had spread to her liver and lungs - a cancer that could have been detected years earlier.
"I'm too young to die, but I was too young to qualify for those tests," she told Newshub.
She was refused a colonoscopy in 2018 when she had severe pain and symptoms, but the doctor told her it was just constipation.
"If they'd taken me seriously then, you know, I wouldn't be in this situation now."
Bowel Cancer NZ says many Kiwis seek help for bowel cancer symptoms but are denied further testing because of their age. The charity is worried about the number of young people being misdiagnosed - people like 43-year-old Jo.
"It's like, who do you have to scream at to actually be heard, and you know, just get a frickin' test?" she told Newshub.
And Accident Compensation Corporation (ACC) data shows Jo isn't alone. The number of cancer misdiagnosis claims the agency has accepted has almost doubled in five years, from 38 claims in 2017/2018, to 70 in the 2020/2021 financial year.
During that period, Southern District Health Board (DHB) had the most claims - 49. Auckland DHB was the next highest with 23.
Cancer Society Medical Director Dr George Laking says it's an issue.
"We certainly see it in New Zealand, just as it's seen in many other countries. I see a great deal of delayed diagnosis in my clinical work as an oncologist," he told Newshub.
"I'd like for us to have a system that works better, where people don't have delays, where the system works together as a whole. I think that is what the Government is trying to achieve with its health reforms."
Dr Laking says access to healthcare is often a problem.
"There are some pretty remote communities and healthcare tends to concentrate in the larger cities."
The Ministry of Health and the Cancer Control Agency told Newshub they don't collect figures on cancer misdiagnosis, so it's hard to know how often it's happening.
The agency's chief executive, Professor Diana Sarfati, says it's dedicated to improving cancer diagnosis and treatment processes.
"Our Quality Performance Indicator programme is a key component of this work, where we measure each DHB on a range of indicators to ensure their best practice is maintained."
Southern DHB declined an interview, saying it will review the ACC data.
Meanwhile, Jo continues to fight cancer for her kids.
"The kids are my priority. I think about it constantly, about them and about what their future looks like."
Bowel Cancer NZ estimates that within the next decade, one-in-10 colon cancers and one-in-four rectal cancers will be diagnosed in adults younger than 50 years.