Cancer survival is increasing across the globe, according to a new study.
But there are wide variations between countries, and the UK is lagging behind comparable nations for many common cancers.
“Inadequate or unreliable data prevent governments from understanding the true nature and magnitude of the public health problems created by the growing cancer burden.” – Dr Claudia Allemani, the London School of Hygiene & Tropical Medicine
Sara Hiom, director of early diagnosis at Cancer Research UK, said the improvements are encouraging, but that more needs to be done to tackle cancers with stubbornly low survival.
The study, published in The Lancet
, looked at more than 37.5 million cancer patients from 71 countries. From 2000-2014 it compared how many of them survived for 5 years after their diagnosis with one of 18 types of cancer.
It found that the USA, Canada, Australia, New Zealand, Finland, Iceland, Norway, and Sweden led the way in survival for most cancers.
Many improvements were also seen for some cancers where survival has tended to be much lower than for others, such as liver and lung cancer.
What’s happening in the UK?
Cancer survival is improving in the UK, with several cancers showing big increases in 5-year survival between 2000 and 2014:
• breast: 80% to 86%
• prostate: 82% to 89%
• bowel: 52% to 60%
• lung: 7% to 13%
But 5-year survival is lower for several common cancers in the UK than in other comparable countries:
• adult brain tumours: 26% in the UK compared to 36% in the USA
• ovarian: 36% in the UK compared to 46% in Sweden.
The UK is often in the bottom half of tables for cancer survival among other EU countries.
Why do the figures matter?
Dr Claudia Allemani, the study’s lead author from the London School of Hygiene & Tropical Medicine, said these statistics are crucial for assessing the effectiveness of health systems and planning better strategies to control cancer.
But data on survival from some countries is limited due to missing information and legal or administrative barriers. In Africa up to 4 in 10 records had incomplete follow-up data.
“Inadequate or unreliable data prevent governments from understanding the true nature and magnitude of the public health problems created by the growing cancer burden,” she said. “This leaves governments poorly equipped to develop national cancer plans that will translate into real improvements in survival for patients.”
Hiom agreed, saying it’s vital that research continues to help better understand how to prevent cancer and diagnose it early when treatment is more likely to be successful.
“Cancer Research UK works with partners across the world with similar health systems and similarly comprehensive information about cancer patients, including how and at what stage they were diagnosed, treated, and their survival,” said Hiom. ”Our International Cancer Benchmarking Partnership
goes a step further to focus on understanding why survival differences exist between countries, offering robust insight to improve the diagnosis and treatment of cancer worldwide.”
Mixed progress for cancers with historically poor survival
Liver and lung cancers typically have poor survival, but good progress has been made in several countries.
Liver cancer survival increased from 11% to 27% in South Korea, and lung cancer survival increased from 8% to 20% in China.
But survival for pancreatic cancer remained low in all countries, with 5-year survival typically less than 15%.
“Greater international efforts are needed to understand the risk factors for this rapidly lethal cancer and to improve prevention, early diagnosis, and treatment,” said Professor Michel Coleman, from the London School of Hygiene & Tropical Medicine and the study’s senior researcher.
Big differences in childhood cancer survival
The figures show particularly wide differences in survival for childhood brain tumours.
While around 8 in 10 children survived for 5 years or more in Sweden and Denmark, less than 4 in 10 children did in Brazil and Mexico. This is likely to be due to availability and quality of diagnostic and treatment services.
Survival for acute lymphoblastic leukaemia, one of the most common types of childhood cancer, has increased in most countries since the mid-1990s.
In the UK and North America UK, 5-year survival is higher than 90%, but remains below 60% in China, Mexico, and Ecuador.
“If we are to ensure that more children survive cancer for longer, we need reliable data on the cost and effectiveness of health services in all countries, to compare the impact of strategies in managing childhood cancer,” said Coleman.
“Inadequate or unreliable data prevent governments from understanding the true nature and magnitude of the public health problems created by the growing cancer burden,”