'Big four' cancer cases slow down but others rise

BY GREER MCDONALD

The rise in cancer cases appears to have levelled out.

However, a report into cancer projections for the next decade shows the tide could turn on "the big four", with a steady rise in other forms of the disease.

According to a just-issued Health Ministry report, the risk of cancer, when adjusted for age, is projected to stabilise over the coming decade for males and decline by 11 per cent for females.

Professor Tony Blakely, of the University of Otago, Wellington, said the stabilising of cases should be celebrated. "We hope it's a turning point."

But with an ageing and growing population, the total number of Kiwis living with cancer would continue to increase, he said.

Cancer is the second leading cause of death in New Zealand, with about 18,500 new reported cases each year.

Three of the biggest reductions in incidence rate were for lung, cervical and colorectal (large bowel) cancers.

Dr Blakely, who peer-reviewed the report, said public health campaigns about cervical cancer and against smoking were thought to have contributed to the decrease. "We should be celebrating the success, the turnaround. But in terms of smoking, we have a lot further to go.

"The rates [of cervical cancer] have come down a lot in the last 25 years, that's good, and one would hope that would come down further with the HPV [cancer-causing human papillomavirus] vaccines."

Doctors were still unsure about the reasons for the slowdown in colorectal cancer. New Zealand had had high rates internationally, he said.

"We think the drivers are the amount of fibre in the diet so, for whatever reasons, that may have changed."

One of the biggest concerns was the rise in leukaemia, lymphoma and thyroid cancer. "They are steadily going up and we don't know why," Dr Blakely said.

"What that says to us is at the moment when we talk about cancer, we talk about the big four – lung, colorectal, prostate and breast – in terms of impact. What this report is suggesting is that that's going to change."

The report projected that the risk of melanoma is projected to stabilise in males and may decline slightly in females.

CANCER PROJECTIONS FROM 2006 UNTIL 2016

10 per cent increase in risk:

MALE

Hodgkin's lymphoma

Liver

Non-Hodgkin's lymphoma

Prostate

Thyroid

FEMALE

Hodgkin's lymphoma

Liver

Thyroid

10 per cent decrease in risk:

MALE

Colorectal

Gall bladder

Larynx

Lung

Pancreas

Stomach

FEMALE

Bone

Cervix

Colorectal

Myeloma

Ovary

Stomach

- © Fairfax NZ News