Global cancer survival rates improve, but wide gaps remain

Cancer patients' survivalprospects are improving, even for some of the deadliest typessuch as lung cancer, but there are huge disparities betweencountries, particularly for children, according to a studypublished on Wednesday.

In the most up-to-date study of cancer survival trends between 2010 and 2014 covering countries that are home totwo-thirds of the world's people, researchers found somesignificant progress, but also wide variations.

While brain tumour survival in children has improved in manycountries, the study showed that for children diagnosed asrecently as 2014, five-year survival is twice as high in Denmarkand Sweden, at around 80 per cent, as it is in Mexico and Brazil,at less than 40 per cent.

This gap was most likely due to variations in theavailability and quality of cancer diagnosis and treatmentservices, the researchers said.

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"Despite improvements in awareness, services and treatments,cancer still kills more than 100,000 children every yearworldwide," said Michel Coleman, a professor at the LondonSchool of Hygiene & Tropical Medicine who co-led the research.

"If we are to ensure that more children survive cancer forlonger, we need reliable data on the cost and effectiveness ofhealth services in all countries, to compare the impact ofstrategies in managing childhood cancer."

Survival often highest in wealthy countries

For the research, known as the CONCORD-3 study and publishedin The Lancet medical journal, the scientists analysed patientrecords from 322 cancer registries in 71 countries andterritories, comparing five-year survival rates for 18 commoncancers for more than 37.5 million adults and children.

For most cancers over the past 15 years, survival is highestin just a few wealthy countries the United States, Canada,Australia, New Zealand, Finland, Norway, Iceland and Sweden.

For women diagnosed with breast cancer in Australia and theUnited States between 2010 and 2014 for example, five-yearsurvival is 90 per cent. That compares to 66 per cent for womendiagnosed in India.

Within Europe, five-year breast cancer survival increased toat least 85 per cent in 16 countries including Britain, comparedwith 71 per cent in Eastern Europe.

The researchers noted that in some parts of the world,estimation of survival is limited by incomplete data and bylegal or administrative obstacles to updating the cancer recordswith a patient's date of death. In Africa, they said, as many as40 per cent of patient records did not have full follow-up data,so survival trends could not be systematically assessed.