Cancer: by 2050 deaths will exceed 18 million (+75%), here are the reasons and how to avoid 42% of them

Despite advances in cancer treatment and efforts to tackle the disease's risk factors, the number of new cases worldwide has more than doubled from 1990 to 2023 (to 18.5 million) and deaths have soared by 74% (10.4 million). Looking to the future, 'without urgent action and targeted funding', it is predicted that by 2050 the number of people newly diagnosed with cancer will reach 30.5 million and deaths will rise to 18.6 million. And more than half of the new cases and two-thirds of the deaths will be concentrated in low- and middle-income countries (LMICs). This is the picture that emerges from a new analysis by the Global Burden of Disease Study Cancer Collaborators, published in 'The Lancet'.

The burden of cancer worldwide is therefore increasing. Between now and 2050, the number of annual cases will rise from 18.5 to over 30 million, an increase of 61%, while deaths will rise by about 75%, from 10.4 to 18.6 million. The increase stems from the combination of three phenomena in particular: population growth, an ageing population and the spread of risk factors that favour the onset of neoplasms. This was revealed in a study by an international collaboration ('Global Burden of Disease Study Cancer Collaborators') and published in the journal The Lancet. "Cancer is a major contributor to the global burden of disease, and our study shows that it is expected to grow substantially over the next few decades, disproportionately affecting countries with limited resources," said lead study author Lisa Force of the Institute for Health Metrics and Evaluation at the University of Washington.

The trend identified by the new study is not new; on the contrary, it is a continuation of a long-term trend. Already between 1990 and 2023, globally, the number of new cancer cases more than doubled; over the same period, the number of deaths increased by 74%. The neoplasms that contributed most to mortality were lung cancer (2.04 million deaths), colon cancer (1.11 million), stomach cancer (935,000), breast cancer (778,000), and oesophageal cancer (577,000). Without intervention, the growth will continue over the next quarter century and it is expected that more than half of the new cases and two-thirds of the deaths will occur in low- and middle-income countries. "The rise of cancer in low- and middle-income countries is an impending disaster," said study coauthor Meghnath Dhimal of the Nepal Health Research Council. "There are cost-effective cancer interventions for countries at any stage of development."

The availability of healthcare systems that guarantee access to timely diagnosis and effective treatment is only one of the necessary steps. Equally important are interventions on the factors that promote disease. Indeed, the study shows that 42% (4.3 million) of the 10.4 million cancer deaths in 2023 were attributable to 44 potentially modifiable risk factors. The risk factor with the greatest weight is tobacco use, which contributed 21% to cancer deaths globally. Then there are poor diet, high alcohol consumption, occupational hazards, air pollution, obesity, and unprotected sex. "With four out of 10 cancer deaths linked to known risk factors, there are huge opportunities for countries to take action, preventing cancer cases and saving lives," said study co-author Theo Vos, of the Institute for Health Metrics and Evaluation, University of Washington.