Emergency hospital presentations and their driving factors may be critical targets for improving cancer control, oncology researchers say.

Their study of 857,068 cancer patients from six countries including Australia, found “notable proportions” were diagnosed through emergency care and had worse prognoses than non-emergency presenters.

Patients with certain tumour types, older age and advanced stage at diagnosis had an increased risk of emergency presentation.

The authors advised monitoring emergency presentations, and “identifying and acting on contributing behavioural and health-care factors” could lead to improved outcomes and should be “a global priority for cancer control” the authors of the study wrote in their paper published in Lancet Oncology.

The study assessed predictors and consequences of emergency presentations, defined as cancer diagnosis within 30 days of emergency hospital admission, across 14 jurisdictions in Australia, New Zealand, the UK, Europe and Canada.

It found emergency presenters made up 24% (9,165 of 38,212) to 43% (12,238 of 28,794) of cancer patients studied, per jurisdiction.

On average, pancreatic cancer had the highest percentage of emergency cases, occurring in nearly half of all cases (30,972 of 67,173), and 34% (1,083 of 3,172 patients) to 60% (1,317 of 2,182) per jurisdiction.

Meanwhile, rectal cancer was least prevalent in emergency versus non-emergency presentations, seen in 12% of patients overall (10,051 of 83,325) and 9.1% (403 of 4,438) to 20% (643 of 3,247) of jurisdictional cases.

Older age, particularly 85 years and over, and advanced stage were associated with increased emergency presentation risk, across the map, the authors reported.

Emergency presenters had “substantially greater risk of 12-month mortality than non-emergency presentations (odds ratio > 1.9 for 112 [100%] of 112 jurisdiction-cancer site strata, with the minimum lower bound of the related 95% CIs being 1.26)”, they wrote.

Jurisdictionally, increased emergency presentation was associated with lower one-year survival for colon, stomach, lung, liver, pancreatic and ovarian cancer, “with a 10% increase in percentage of emergency presentations in a jurisdiction being associated with a decrease in 1-year net survival of between 2.5% (95% CI: 0.28–4.7) and 7.0% (1.2–13.0)”.

“We show that emergency presentations are frequent, have adverse prognostic implications, and probably contribute to international differences in cancer survival,” the authors wrote.

“The findings support incorporating measures of emergency presentation both in international studies comparing cancer survival between jurisdictions, and population-based surveillance to support cancer control efforts within jurisdictions.”

Colorectal and lung cancer screening, along with public health awareness campaigns and healthcare system reform have already had some success.

Between 2006 and 2015, England saw “substantial reductions in emergency presentations” which were attributed to improved symptom awareness and a healthcare system redesign that left suspected cancer patients waiting just two weeks to access specialist care.

“The size and speed of this decline exceeds what would have been expected by changes in incident cancer site case mix, and is unlikely to reflect changes in tumour biology,” the authors wrote.

Not all emergency presentations are preventable, however, with some “resulting from rapidly advancing disease (at times with few or no prodromal symptoms)” and featuring haemorrhage, gastrointestinal obstruction or other complications requiring urgent hospital care.

Minimising emergency presentations and improving outcomes will lie with studying, identifying and acting on modifiable tumour, patient and healthcare factors and should be a priority, the authors concluded.