Mapping National Definitions, Classifications, and Policy Approaches to Poor-Prognosis Cancers Across the G7 Cancer...

In 2023, the G7 Cancer Initiative was launched by Australia, Canada, France, Germany, Japan, the United Kingdom, and the United States with the aim of enhancing global cancer control, and with poor-prognosis cancers as a priority. To facilitate effective collaboration among G7 Cancer, we aimed to address the lack of standardized definitions and coordinated initiatives across countries.

We examined how the G7 Cancer Initiative countries defined poor-prognosis cancers, objectively classified them, quantified their burden, and assessed national response strategies. A review of national cancer plans was conducted together with an expert email survey to evaluate definitions and classifications. Poor-prognosis cancers were identified based on 5-year net survival (NS) below 30% and a mortality-to-incidence (M/I) ratio over 0.75 using CONCORD-3 and Global Cancer Observatory 2022 data.

Pancreatic cancer was consistently categorized as a poor-prognosis cancer, while some countries also included liver, esophageal, stomach, and some brain cancers. For lung cancer, classification varied depending on the definition used. These six cancers accounted for a major share of cancer deaths, with lung (18%-23%) and pancreatic (6%-10%) cancers contributing the most. National strategies differed, with Australia, France, and Japan implementing specific policies for poor-prognosis cancers, while others addressed them indirectly or not at all.

To enhance cancer outcomes for poor-prognosis cancers, the G7 Cancer Initiative should coordinate efforts through joint programs focused on early detection, treatment, and policy alignment. Standardized definitions and collaborative action are essential to strengthening the global poor-prognosis cancer response.