Prostate News

Why do Northland men die of prostate cancer at such high rates?

Categories: Medical

Northland men die from prostate cancer at almost three times the rate of men in north Auckland.

Of the “big four”, prostate cancer showed by far the greatest regional variation. With 35 deaths per 100,000 men, the Northland rate was more than double the national rate of 16.8 per 100,000 and almost three times Waitemata DHB’s rate of just 12.3 deaths per 100,000.

Northland urologist Tony Nixon is at a loss to explain the higher rates, believing treatment quality and access are as good in his area as anywhere else.

Lower Hutt prostate support group leader Bill Guthrie’s cancer was picked up through PSA testing and he would like to see a national testing regime.
Lower Hutt prostate support group leader Bill Guthrie’s cancer was picked up through PSA testing and he would like to see a national testing regime.

Northland DHB blames its high rates on the makeup of its population, which is 34 per cent Maori, with one third of residents falling into the poorest of five deprivation categories. However, Counties Manukau DHB, which also has about one third of its population in the “most deprived” category, had the second lowest death rate.

Prostate cancer research by Waikato professor Ross Lawrenson found Maori patients tend to have fewer investigations, lower treatment levels and poorer survival rates. They are also diagnosed later.

Prostate cancer deaths rates by DHB
See chart for rates around New Zealand

The biggest question around prostate cancer is screening. In the past decade, there’s been increasing use of the PSA blood test. Undertaken regularly, it can point to early signs of prostate cancer. But it’s highly controversial, as it has a high rate of false positives. Because prostate cancer is generally a slow-growing cancer affecting older men, screening can lead to men having treatment with life-altering side effects such as incontinence and impotence for a disease that would never have caused them symptoms before their death.

Wellingtonian Bill Guthrie was diagnosed with prostate cancer at 50, having started PSA testing a year earlier, after his brother-in-law died of the disease having been diagnosed too late to be cured. He’s a keen advocate of the testing given he would have been considered low-risk, as a healthy fit man with no family history. He’s also frustrated that some GPs still try to talk men out of having PSA tests.

“Six hundred men a year die of this – they don’t have to die.”

Guthrie would also like to see public funding of low-dose rate brachytherapy, which is only available in private hospitals. The one-step procedure involves implanting radioactive seeds as an alternative to daily radiotherapy in hospital.

New Zealand has rejected a publicly funded screening programme, but the growth in private PSA screening has left the public health system in a quandary, says Urological Society NZ chairman Stephen Mark.

Confusion and controversy reigned over when men with high PSA levels should be referred to public hospitals. A man in one region might be referred and treated, whereas a man in another region with the same PSA level might have been turned away by the public system. Work has been done in the past few years to standardise that approach, he says.

While a national screening programme doesn’t make economic sense, he concedes that without one poorer survival rates for Maori are unlikely to be reversed.

“There’s no question there is an equity imbalance based on economics.”

Otago University Cancer Control and Screening Research Group director Diana Sarfati, says the difficulty with prostate cancer is ongoing uncertainty about how to treat it. For colorectal cancer, you cut it out – no question. But because prostate cancer is generally slow-growing, treatment options vary from watchful waiting to surgery, chemotherapy, radiotherapy or hormone manipulation.

That’s reinforced by Northland prostate cancer patient Paul Botell’s experience. Among his Whangarei support group there are as many treatment types and outcomes as there are men.

“It’s a bit of a crap shoot. No two stories are the same. No two people have the same reaction to the same treatment.”

The 69-year-old chose to have his prostate cut out 18 months ago, after regular PSA testing helped identify a growing cancer. He initially suffered terrible incontinence but now has that almost under control.

The Whangarei Heads retiree had no trouble getting treatment and says his care was better than that in his former homeland, the United States. He wonders if the region’s staunch farming community’s reluctance to get tested are partly responsible for high Northland death rates.

Wellington radiation oncologist Professor David Lamb says there is huge variation in the way treatment options are offered around the country. The ethnic disparities also need addressing, he says.

However, he’s hopeful his RADAR research trial will help doctors discover which cancers are fast-growing and need aggressive treatment and which are less dangerous.

“It’s becoming very clear that you can identify these bad cancers and you can give them more treatment upfront and you can get better long term results.

“There’s a perception that prostate cancer is a pretty harmless condition. It’s almost an honour to have, it’s so trivial in what it does to you. You don’t even have to look at the cancer statistics to realise that’s absolute nonsense.”

*Statistics are for 2010-2012. Cancer death rate map shows areas with rates significantly higher or lower than the national rate, calculated using the Keyfitz method.