She said that could be because the emergency department was more convenient, open all hours, and free. Some also found it a more familiar environment, she said.
"The trend for some people to come to ED rather than go to a GP surgery can also suggest they are not familiar or have a level of engagement with a GP that would make the GP their first port of call for health."
She said there were also "health literacy issues" often reflected in a patient not recognising concerning symptoms and then failing to act on them.
"This may be in part because of underlying fears associated with the possibility of a cancer diagnosis and sometimes reluctance to see health professionals, when the patient in the past may have received health advice which they chose not to follow at that time."
She said patients not seeing their GPs in the early stage of the disease could mean that by the time they presented to ED, they were sicker and the cancer was more established.
"This can mean a lower chance of cure or control of the symptoms."
Miss Wilkie said what continued to be positive was that people, once diagnosed, were continuing to receive chemotherapy and radiotherapy through Waikato within the required time frames. "In the past, sicker patients who have presented later have been diagnosed very quickly and had access to treatment quickly, but had less chance of a lasting cure."
She said with more effective treatment now available it was even more important to have an early diagnosis. "If you have an aspect of your health that you are worried about, don't put it off. Make an appointment with your doctor ..."
She said being enrolled with and visiting a GP could help provide continuity of care, which would be difficult if presenting to various services only when acutely unwell.
Waikato/Bay of Plenty Cancer Society communications manager Maria Low said it was important for people to know their own body and normal habits, and if anything changed to see their GP.
"Also, if possible, learn your family history so your GP has that information too because it could be relevant."
She said the Cancer Society supported any initiative that continued to improve the quality and timeliness of services for patients along the pathway and improve clinical outcomes.