An international comparison study of stage of colorectal cancer at diagnosis: how does New Zealand compare?
OBJECTIVE
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?


METHODS
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.


CONCLUSIONS
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.
Samson
Paul
P
Department of General Surgery, Wellington Hospital, Capital & Coast District Health Board, Wellington. teamsamson@hotmail.com
O'Grady
Gregory
G
Keating
John
J
D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008403:Mass Screening / Q000379:methods* / Q000706:statistics & numerical data; D009367:Neoplasm Staging / Q000379:methods* / Q000706:statistics & numerical data; D009517:New South Wales / Q000453:epidemiology; D009520:New Zealand / Q000453:epidemiology; D012189:Retrospective Studies; D013997:Time Factors; D006113:United Kingdom / Q000453:epidemiology; D014481:United States / Q000453:epidemiology