Aim To estimate the number of colon cancer patients in New South Wales (NSW) Australia requiring cancer care in the future.

Methods Prevalence of first primary colon cancer was estimated and projected forward, by stage of clinical care (initial care, long-term survivors, monitoring, and last year of life), for 2007–2016. Then using data from a patterns of care study for colorectal cancer, we estimated the type and amount of treatments that will be needed by colon cancer patients in each stage of care. Finally, data on metachronous tumours or second primary colon cancers were used to estimate the additional number of patients who will require care.

Results In NSW in 2006, there were 17 687 patients aged 18–84 years alive with a past diagnosis of colon cancer. By 2016, this number will have increased to 22 262. The expected numbers of patients vary by stage of care with the majority in the monitoring stage (41.4%) or being long-term survivors (40.7%). There will be at least 1389 men and 1135 women requiring initial surgery for colon cancer in 2016. Of these 431 men and 352 women will also require adjuvant chemotherapy. In addition, there will be 741 patients with metachronous tumours or second primary colon cancers who will also need care in 2016 with 56% of them in the monitoring stage.

Conclusions These estimates reveal that in NSW the numbers of colon cancer patients requiring care for colon cancer are projected to rise by over 25% from 2006 to 2016.