What is Bowel Cancer?

Defining Bowel Cancer

Most commonly referred to as bowel cancer in New Zealand, but also known as colorectal cancer or colon cancer, it is a cancer formed from uncontrolled cell growth in the colon or rectum (parts of the large intestine). The analysis shows colon and rectal tumours are genetically the same cancer and often referred to as colorectal cancer or colon cancer.

Risk factors for bowel cancer include heredity, colon polyps, and long-standing Crohn's disease and ulcerative colitis.

Bowel cancer often starts from small, noncancerous polyps that form on the inner walls of the colon or large intestine.

Some of these polyps may grow into malignant cancers over time if they are not treated. It is estimated that polyps will occur within 15-20% of adults.​

It has been reported that up to 50% of polyps greater than 2cm are cancerous, but all but the smallest polyps should be removed to ensure they do not turn cancerous.

If they do turn into cancer, these cancer cells can travel into the bloodstream or lymph nodes and other parts of the body typically the liver and the lungs.

Bowel Cancer Statistics in New Zealand

Bowel cancer is the second largest cancer killer in New Zealand with more than 3000 people diagnosed every year and more than 1200 people dying from it.

​New Zealand has one of the highest bowel cancer rates in the world per capita with men now being slightly more at risk.

Up to 90% of people diagnosed can be saved if caught early enough. Remove the polyps, remove the risk!

The number of people diagnosed is expected to increase as the government stages its rollout of the National Bowel Screening Programme authorised by Parliament in 2016.

The current criteria for free public screening is only available for New Zealanders between the ages of 60 to 74 years old.

​This age bracket accounts for approximately 36% of bowel cancers diagnosed in New Zealand.​ If the age was reduced to 50 it is estimated almost a further 13% could be saved.​

The New Zealand Cancer Registry, run by the Ministry of Health since 1948, records all cancer registrations each year.

​Total Colorectal/Anal cancers were 3,081 (last registered in December 2017 - this most current information available was released in December 2019).

  • 298 under age 50 (9.67%) increased from 2016
  • 414 between the ages of 50-60 (13.44%) increased from 2016
  • 1118 between the ages of 60-74 (36.28%) National bowel screening programme age criteria decreased from 2016
  • 1251 over the age of 75+ (40.6%) decrease from 2016

Scientists believe a diet high in animal fats and low in fruit and vegetable fibre may contribute to the development of bowel cancer. Current research is also addressing inequalities in New Zealand, including reasons for survival differences between Māori and non-Māori.

Whatever your ethnicity, prevention and early detection and screening is the key.

Over half of New Zealanders are unsure of the symptoms of bowel cancer…are you?

Latest Posts

The latest articles from Bowel Cancer Foundation Trust

Stem cell function may explain higher colon cancer rate in males

Stem cell function may explain higher colon cancer rate in males

Colon cancers have a higher incidence in males around the world, which is in part related to much higher androgen levels in males compared to females ...
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Pharmacy home Bowel Screening Kits on hold due to COVID

Pharmacy home Bowel Screening Kits on hold due to COVID

A number of processing delays of the private home bowel screening kits purchased in Pharmacies over the counter or online have forced the kits to be ...
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Tairawhiti joins National Bowel Screen Programme

Tairawhiti joins National Bowel Screen Programme

Free bowel screening will soon be available in Gisborne and surrounding districts with Tairāwhiti this week joining the National Bowel Screening Progr...
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Charity Achievements

Key milestones reached by Bowel Cancer Foundation Trust


Dollars distributed in the last 12 months to fund research and provide equity of care and better patient outcomes


Bowel cancer survivors rehabilitated after gruelling treatment helping to reduce cancer re-occurrence


Bowel screening kits provided to Kiwi’s who do not qualify for free public screening to detect bowel cancer early


Years we've been making a difference for bowel cancer patients in New Zealand