February 12, 2025 Author : Susana Ouro The latest data from the Global Cancer Observatory , the world's epidemiological cancer registry, colorectal cancer cases are increasing , particularly in individuals under 50. In older age groups, the percentage of new cases remains constant, but in younger age groups the is an important increase in both rectal cancer and colon cancer, or colorectal cancer. And predictions are that this trend will continue and will be accompanied by a 30% increase in prevalence by 2030. The percentage of new cases of colorectal cancer remains higher in men, but they are now younger. More cases at younger ages It is not very clear why this is happening. It is probably a social problem related to diet or exposure to other phenomena that we have not directly related to this cancer. Colorectal cancer is certainly associated with obesity. Therefore, these data may be a direct reflection of overweight and obesity numbers. But there will certainly be several factors involved. There is no clear relationship between heredity and colorectal cancer. Socioeconomic, hygiene and dietary factors associated with processed foods seem to have a much close relation. We know that some people have a direct risk of colorectal cancer, but we do not know if they explain this incidence increase in younger populations. Obesity, consumption of processed foods, sedentary lifestyle, smoking are very prevalent in Western societies, much more so than in non-Western societies. The most important factor will certainly be obesity. And everything is associated with it, such as lack of exercise and regular behaviors associated with mobility. The truth is that the overweight and obese population continues to increase. And hence the great impact of this type of cancer on younger populations as well. On the other hand, Western societies, especially younger populations, are eating diets that more processed foods and foods with a high energy concentration, with excess calories. All together will probably create the so-called metabolic syndrome . If, in addition, there is still a hereditary factor for colorectal cancer – which will have a weight of 5%-10% in its incidence – then we will have an explosive combination and a possible explanation for the incidence increase in this cancer. Earlier screening In any case , these numbers force us to be much more attentive to early-onset colorectal cancer (colorectal cancer in young people, defined here as those under 50 years old). There is still no data that show if this cancer at younger ages is aggressive, although empirically it appears to be more aggressive. This is according to our experience, the experience of those who perform colorectal surgery: most of our younger patients, when the diagnosis is made, already have metastases. This is why the European and American societies of gastroenterology have recommended lowering the age for starting colorectal cancer screening. Portuguese society will also move forward in this direction, as stated in the conclusions of the recent national and European colorectal surgery congresses. In Portugal, colorectal cancer screening is carried out from the age of 50, with one of 2 tests: Testing for occult blood in feces. Colonoscopy. In our country, this screening is done mainly through occult blood in feces , due to an evident lack of capacity to perform colonoscopies. However, colonoscopy allows for more accurate screening, is a very safe exam, with no difficulties whatsoever in performing it. What scientific medical societies are trying to do in Western countries is to alert health authorities to the fact that colorectal cancer screening must be reduced to the age of 45. Most countries will adopt this indication. And we must do that too. Colorectal cancer treatment Treatment options for colorectal cancer are primarily surgical. But therapeutic options are always evolving. New medicines, new therapeutic combinations, immunotherapy… This evolution is happening across all oncological diseases. Immunotherapy, for example, has an extraordinary response in a certain subtype of colorectal cancer. Research on these drugs is producing new results every day, so it is to be expected that more will be known. In two years, there will probably be a lot of new developments in this area. Radiotherapy is also increasingly providing a response for certain types of patients , and we are increasingly confident in what we do in this area. So, from a surgical point of view, the techniques themselves are also changing. Surgical robotics, for example, is very safe in both colon and rectal cancer. It is therefore a useful and very safe tool. Main ideas to remember Colorectal cancer cases are increasing in younger age groups. The prevalence of colorectal cancer will continue to increase and is associated with lifestyle. Doctors should be more alert and indicate an earlier screening. In the short term there will be a great evolution in therapies, especially chemotherapies and immunotherapy. Robotic surgery is consolidated as a treatment tool, with evidence of safety in this type of cancer. Meet the general surgery clinical team from Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
