Colon cancer management in New Zealand: 1996-2003

This study provides an overview of colon cancer diagnosis and treatment in New Zealand between 1996 and 2003.

A sample of 642 individuals (308 Māori and 334 non-Māori) with histologically confirmed colon cancer diagnosed between 1996 and 2003 were identified from the New Zealand Cancer Registry. Details of referral, investigations, diagnosis, treatment and follow-up were obtained from clinical notes and pathology records.

Fourteen percent of patients with colon cancer presented at an early stage, while 21% presented with disseminated disease. Most colon cancer was diagnosed in public hospitals, although nearly one-quarter was diagnosed in private, and one third of patients presented acutely. The use of colonoscopy for diagnosis and CT for staging increased considerably over the period studied. Definitive treatment was usually undertaken within 4 weeks of seeing a specialist, and 94% of patients were treated with surgery, one-fifth of which was emergency surgery. Most surgery was undertaken by general surgeons in public hospitals. One quarter experienced some post-operative complication. Two thirds had other chronic conditions documented in their hospital notes. Of those presenting with regionally advanced disease, 69% were offered adjuvant chemotherapy, and 54% of those presenting with metastatic disease were offered palliative chemotherapy. The use of adjuvant and palliative chemotherapy increased over the time of the study.

The pattern of colon cancer found is consistent with the largely unscreened New Zealand population. Considerable changes were seen in the use of investigations and chemotherapy for colon cancer over the time period of the study, bringing New Zealand closer to international best practice management.