A Southland cancer patient who needs regular surgery to control the growth has faced weeks of delays after a cancellation.

David Evans is bracing for the possibility his kidney cancer has spread - or he will be unable to keep his kidney - when he eventually returns to the operating theatre on Thursday.

The Winton man was scheduled for surgery two months ago, but it was postponed and then later cancelled.

It follows the resignation of two urologists - which Health New Zealand first confirmed in March - followed by "additional unanticipated absences", leaving the region with no permanent full-time urologists.

Health New Zealand said patients were being seen by one primarily Southland-based urologist and one specialist who visited weekly, while permanent full-time replacements were sought.

Evans said he had undergone surgeries every three to four months since last year to cut away the cancer.

His most recent operation was in January at Southland Hospital and the next was scheduled for 14 May, he said.

"They came and saw me on the day, very apologetic, saying that because of theatre overrun they would rebook me for the following week - which they did. But I received a phone call on the Monday to tell me that all surgeries had been cancelled and there was no follow up at all," Evans said.

He called the hospital countless times to find out when he could be rescheduled, but each time he was transferred to a voicemail at the urology department, he said.

"I just couldn't believe the lack of follow-up... I hadn't received anything until last week when, thank God, they said we've got a surgery booked in for this coming Thursday."

Hospital staff did not tell him about the urologist resignations - instead he read about them in the news as he sought an explanation for the change in plans, he said.

"I need the three and four month operations... this is coming up to about seven months now. With time comes longer growth periods and I don't know how far the cancer has travelled," he said.

Evans said he had no criticism for the doctors and nurses he had dealt with, but high-level decision-makers needed to show greater transparency and accountability.

"People are being sent home and are slowly dying because they cannot get into the hospital and that's tragic. It really is."

Health New Zealand apologises

Health New Zealand declined RNZ's request for an interview but - in a statement - southern group director of operations Craig Ashton said the organisation sincerely apologised for the treatment delays experienced by Evans.

No procedures could go ahead on the day Evans' surgery was scheduled because of unexpected leave from the treating urologist, he said.

"We acknowledge that any delay for surgery can be distressing and patients can be assured that surgeries and procedures are prioritised based on patient acuity and only deferred where absolutely necessary and only if it is clinically safe to do so," Ashton said.

"The decision to defer or delay care is never taken lightly."

Health NZ confirmed two urology positions in Southland remained vacant.

"We are exploring all avenues to improve our capacity, including ongoing recruitment efforts, seeking support from locums and Health New Zealand staff from other areas, and outsourcing where possible - both locally and in other locations in the South Island," Ashton said.

Long-standing issues criticised

Trish Wright - coordinator of the Southland Support Group of the Prostate Cancer Foundation - said she was absolutely gutted to hear the two urologists had resigned earlier this year.

Prostate cancer patients typically needed treatment sooner rather than later and relied on timely access to urologists, she said.

"If they are eligible for surgery and if it's recommended, our two urologists would certainly have done it in a timely fashion in past. I can't imagine how long these guys are going to have to wait when there is no urologist down here or urology surgeon at least," Wright said.

"It's mind-boggling what has what has happened with both of them going."

It seemed Health NZ had not done enough succession planning to prepare for the staffing gap and that was disappointing, she said.

"We know how hard it is to get doctors down here anyway. Imagine how big the waiting list is going to be by the time they manage to get another urologist down here... things are just going to get worse."

Health NZ's latest quarterly report showed cancer patients in Southland had the second-longest wait times for treatment anywhere in the country, behind Canterbury.

As of March, 18.9 percent percent of the region's patients were waiting longer than 31 days for their treatment to start.

Southland Kidney Society president Nobby Clark said the region's residents had long suffered from a postcode lottery, where speed of access to specialists and surgery appeared to be dictated by geography.

"You don't have to go too far to find shortages in just about every area you want to go to and certainly Southland Hospital suffers from that," he said.

Cancer Society Southern chief executive Christine Prince said it was common for Southlanders to wait weeks or even months for treatment.

"There seems to be long, long, ongoing issues involved with resourcing and access of care for patients across Otago-Southland. This encompasses... bladder cancer, prostate, kidney cancer... it's quite significant," she said.

"One of the key frustrations is people having to wait at a time of great uncertainty. Whether it's the first appointment, then being put on a wait list or getting treatments, it's ongoing."