28/10/12 1:35 PM An international comparison study of stage of colorectal cancer at diagnosis: how does New Zealand compare? Page 1 of 8 http://journal.nzma.org.nz/journal/122-1294/3582/ Table of contents Current issue Search journal Archived issues NZMJ Obituaries Classifieds Hotline (free ads) How to subscribe How to contribute How to advertise Contact Us Copyright Other journals Journal of the New Zealand Medical Association, 08-May-2009, Vol 122 No 1294 An international comparison study of stage of colorectal cancer at diagnosis: how does New Zealand compare? Paul Samson, Gregory O’Grady, John Keating Abstract Aim The high incidence rates of colorectal cancer (CRC) in New Zealand (NZ) are well publicised. Minimal information is available comparing national extent of this disease at time of diagnosis with other countries, especially countries now performing screening for CRC. Just how late do our cancers present? What is the difference compared with other countries now performing screening? Method Data were retrieved and analysed from the World Health Organization and Cancer Registries in New Zealand and five other countries from 2001–2004. Extent of disease was classified as localised, regional, distant and unknown. Results NZ has the lowest percentage of surgically curable localised disease (28%) when compared with Australia (New South Wales) (34%), United Kingdom (42%), American (SEER-9) (40%) and Hong Kong (35%) data. 20% of disease at diagnosis in NZ is metastatic. Conclusion By international standards, NZ has a marked and previously undefined low rate of early stage diagnosis of CRC. Extent of disease is more advanced in New Zealand patients than in other countries with recently commenced screening programmes (e.g. Australia and the UK). In 2001, NZ also had the highest age-specific incidence of colorectal cancer in the 50–70 years age group, when compared with Australia, USA, UK and Japan. Colorectal cancer will continue to be a significant health issue for the NZ population, with predicted increasing total numbers of people affected, and increasing costs of chemotherapy for advanced cancer. The concerning international comparisons shown in this article further emphasize the need for more immediate strategies to improve rates of early stage colorectal cancers at time of diagnosis. Recent articles published in the New Zealand Medical Journal discuss various aspects of colorectal cancer in New Zealand, 1 including the fact that incidence rates of colorectal cancer (CRC) in New Zealand (NZ) are amongst the highest in the world. With 2624 new cases registered in 2001 alone (an age-standardised rate of 43.7 per 100,000 population [NZHIS]), 2 colorectal cancer is among New Zealand’s most significant health problems. There is a substantial volume of quality evidence that screening for CRC leads to a modest but significant reduction in CRC mortality. 3, 4, 5 In a population offered screening over an 8-10 year period, a 16% reduction in mortality was found in one meta-analysis. 6 Furthermore, with increasing duration of screening programmes, a reduction in cancer incidence is predicted, in part due to early removal of adenomas. Despite acknowledged potential harms stemming from false- positive results and subsequent injury from investigation or treatment, the consensus findings are for overall benefit in favour of screening, 6 provided participation rates and resources are adequate. 7 Colorectal cancer screening is of topical interest in NZ at present. Accurate and recent epidemiological data for CRC is necessary in discussions regarding CRC screening. Incidence and mortality figures have been published showing NZ rates at the highest end of the international