Bowel cancer taking big toll on Kiwis

It's the disease no one wants to talk about, but early intervention can tame this scourge. RON TAYLOR and KATHERINE HOBY report.

New Zealand has one of the highest rates of bowel cancer deaths in the world - second only to Canada.

And it is one form of cancer people seem unwilling to talk about.

More Pakeha contract bowel cancer and die of it than Maori and it ravages our population because we do not seek treatment early enough.

Why is New Zealand's rate of bowel cancer so high?

The Cancer Society says there are a number of reasons, but the main ones appear to be environment, age and diet. New Zealanders eat a lot of meat, which may be a factor.

Bowel cancer is second only to lung cancer in the number of deaths and new cases reported each year.

Bowel cancer - cancer of the colon and rectum - kills more than 1100 people a year, and while those over 40 are more likely to get it, it may occur in younger people. The risk for both sexes increases with age.

But, like most cancers, it can be cured if detected in the early stages and before it has spread to nearby organs such as the bladder or to other parts of the body via the bloodstream or lymphatic system.

Auckland oncologist Dr Paul Thompson says about half of bowel cancer patients are cured by surgery alone and another 10 per cent by additional anti-cancer therapies.

About 2500 new cases of bowel cancer are diagnosed each year and it affects men and women in nearly equal numbers.

Latest figures from the Ministry of Health, for 1996, show that 1247 men and 1187 women were diagnosed. Recorded deaths were 587 men and 546 women.

Dr Thompson blames the lower level of awareness about bowel cancer in part on publicity given to other forms of cancer in recent years.

The anti-smoking, breast screening and cover-up-from-the sun campaigns have heightened awareness of lung, breast and skin cancer, and public inquiries into cervical cancer botches have grabbed the headlines.

But fewer people die from these cancers - 685 (including four men) from breast cancer in 1996, 194 from melanoma and 82 women with cervical cancer.

The problem is that many bowel cancer patients present with either a spread of their cancer at diagnosis or develop "secondaries" in other organs because the disease was further advanced than first thought when surgery was undertaken.

Secondaries usually occur within two to three years of the initial surgery.

Dr Thompson says it is becoming apparent that the newer chemotherapy drugs, used in combination, increase the chance of some patients' having their secondaries successfully operated on when previously this was unlikely.

The Ministry of Health has recently added two of them - Camptosar (iriontecan), developed by Pharmacia, and oxaliplatin - to the free list of drugs available in public hospitals from October 1.

Previously, some patients paid up to $30,000 for a course of Camptosar while others got it free, depending on where they lived and the allocation of funds by regional cancer centres.

While Camptosar is not a cure for patients with established secondaries, it may add to a patient's quality and length of life, although it is not suitable for all, says Dr Thompson.

"We're hoping that trials [at present under way] will show that, when given immediately after primary surgery for bowel cancer, these newer drugs will increase cure rates," he says.

"The results should be clear within two to three years."

Wellington cancer specialist Dr Michael Findlay says the telltale sign for people is a change in bowel habits.

These include blood or mucus in the bowel movements, diarrhoea or constipation, colicky pain in the stomach and tiredness or paleness from anaemia.

These symptoms don't necessarily spell cancer and sometimes they appear only after the cancer has spread.

"It's very tricky, but just because you're young [and any of these symptoms occur] don't assume that it's not bowel cancer," he says.

"The tragedies that I see are people aged 25, 30, 35, who don't have a family history of colorectal cancer and who turn up with rectal bleeding for a year but the penny hasn't dropped with the referring doctor until fairly late in the piece.

"It is important that rectal bleeding is evaluated properly and that specialist advice is sought."

The chances of developing bowel cancer increase with age - more than 90 per cent of registrations are people over the age of 50.

Genetic or familial cancers are more likely in people who present at a younger age, but only about 5 per cent of colorectal cancers are in this category.

"The thing is to remember that bowel cancer is a relatively simple thing to get sorted out," he says.

"While people don't relish the thought of the tests involved in that part of the body, it's better to present early than too late. We can do much more than people realise if we get in early enough."

* Information supplied by the NZ Cancer Society and Pharmacia.