In developed countries, cancer sees its incidence increase year by year. It is claiming more and more victims, and it is already the second cause of death behind cardiovascular diseases. However, there is a paradox: while the cancer incidence increases, the mortality rate (a value different from the total number of cases) decreases.
Cases are increasing, but they are becoming less deadly
The increase in the incidence of cancer is a well-documented fact, as indicated by the forecasts of the Spanish Society of Medical Oncology for the year 2023. In the Spanish case, which is in many ways similar to that of other Western European countries , this increase in cases is explained by four fundamental factors: population growth, population aging (a key risk factor), exposure to environmental and other risk factors, and improvements in early detection.
Something similar happens with the net number of deaths due to cancer. As reflected in the report European cancer mortality predictions for the year 2023 with focus on lung cancer published in the specialized media Annals of Oncology and elaborated with data from the WHO by experts from several European universities, the increase is mainly due to the population growth and aging.
On the contrary, to understand the decline in the mortality rate (the number of deaths that occur within a given number of patients) from cancer, it is necessary to look at the characteristics of each case.
Risk factors and medical advances
For example, in lung cancer, the one that causes the most deaths in Europe, the influence of smoking (which has been declining thanks to public policies in this regard) is essential to understand the trends. Precisely, in this case the mortality rate increases only in women over 65 years of age, reflecting a trend whereby the number of women smokers increased a few years ago. In the rest of demographics, it decreases.
Precisely, smoking is one of the risk factors whose importance has been decreasing in recent years, along with others such as exposure to certain environmental pollutants (such as asbestos) that have been subject to more or less strict regulations. On the contrary, the relevance of risk factors such as obesity or alcohol use It is growing.
In fact, the report attributes the good news mostly to the different medical advances in detection and treatment cancer in recent years. Thus, although these advances are more or less generalized across the different types of tumor, they explain the exception that is the deadliest of cancers: pancreatic cancer. In this case (in which mortality in men either remains stable or decreases slightly, and in women it either remains stable or increases depending on the country), the improvements in diagnosis and treatment have been much less significant. than in other cancer types.
the work to be done
In general, the conclusions are positive. The mortality rates of the types of cancer that cause the most deaths (lung, colorectal, breast and prostate) they go down consistently. Even in the work it is said that assuming that the trends continue, the objective of reducing deaths from cancer by 35% by 2035 could be achieved.
For this, it is necessary to continue working in the right direction. The authors advise not to give up on the smoking control strategies, for example by defining age cohorts from which the purchase of tobacco products is not allowed. It is also important to emphasize the identification of populations at risk and the implementation and improvement of screening and diagnosis programs.
Similarly, they recommend paying more attention to the control of obesity and overweight, improving dietary habits including the control of alcohol consumption and the organization of screening programs against colorectal cancer. Other measures such as vaccination against carcinogenic viruses such as the human papilloma virus (HPV) or the hepatitis B virus can achieve even greater reductions in mortality from certain types of cancer.
References
SEOM.ORG. Cancer figures in Spain 2023. SEOM.ORG (2023). Consulted online at https://seom.org/images/Las_cifras_del_Cancer_en_Espana_2023.pdf on 03/09/2023.
M. Malvezzi, C. Santucci, P. Boffeta, F. Levi, C. La Vecchia, E. Negri et al. European cancer mortality predictions for the year 2023 with focus on lung cancer. Annals of Oncology (2023). DOI: https://doi.org/10.1016/j.annonc.2023.01.010