Colorectal cancer may be on the rise among young people – 04/25/2023 – Equilibrium

American and European studies that pointed to an increase in cases of colorectal cancer among younger people in the regions drew attention to the Brazilian reality. According to experts, Brazil is following the trend, but there is a lack of national data to confirm the scenario. The Inca (National Cancer Institute) confirms the increase, but is still working on a report on the subject.

Sedentary lifestyle, diet rich in ultra-processed products and exposure to pollutants are some of the possible causes of the increase in cases of bowel cancer in people under 50, an age group considered young to have the disease.

A study published in March by the American Cancer Association estimates that the number of colorectal cancer diagnoses in the US in 2023 will reach 153,000. About 13% of these cases will be in people under 50, which represents a 9% increase in cases in this age group since 2020.

A study published in 2020 in the journal of gastroenterology and hepatology of the BSG (British Society of Gastroenterology), highlighted the increase in cases of colorectal cancer in young adults aged 20 to 49 years in Europe and the US.

In Brazil, the Inca estimate is 45,630 thousand new cases of colon and rectum cancer for each year from 2023 to 2025. This is the fourth type of cancer with the highest incidence, behind skin, breast and prostate cancer . Colon and rectum cancer is the third most common in the world, with 1.9 million new cases, according to the institute.

“Between 2011 and 2016, the increase in cases of colon and rectum cancer was 35% in patients under 50 years old, according to a survey by the Cancer Institute of the State of São Paulo. This trend continues and the increase has been in the order of 2% a year”, says Paulo Hoff, professor of oncology at USP (University of São Paulo) and president of Oncologia D’Or.

The study reviewed the medical records of 5,806 patients with bowel cancer who had the disease confirmed by biopsy and whose data had been forwarded to the Cancer Institute of the State of São Paulo between January 2011 and November 2016. Of this total, 781 patients with under 50 years old. The mean age of these patients was 42 years. Those with a family history were 20.9%, while women represented 57.4%.

According to Hoff, there was an average age of 67 years for the incidence of colon cancer. In recent decades, however, cases before the age of 50, which were rare, have increased in different countries. Although it is not yet clear what motivates the increase, possible causes would be a sedentary lifestyle and exposure to pollutants, in addition to diets rich in ultra-processed foods.

Antônio Carlos Moraes, gastroenterologist and director of the Brazilian Federation of Gastroenterology, says that high-fat diets alter the intestinal flora. “This change in the microbiota favors carcinogenesis [alteração celular] of the intestine”, he says.

The gastroenterologist observes an increase in patients over 45 years old with polyps in the intestine, which are alterations that can progress to cancer. The disease in the organ, also called colon and rectum or colorectal, results from genetic alterations of the cells that line the intestinal mucosa, leading to the presence of tumors in the region.

Alexandre Jácome, oncologist and director of the SBOC (Brazilian Society of Clinical Oncology), notices an increase in cases of younger patients with colon and rectal cancer in his office. The oncologist highlights the importance of more data and studies on the national reality.

“As everything indicates, this phenomenon is not restricted to the United States. It affects countries in Europe, countries in the North and some countries in Latin America. But, in our midst, we still lack data”, he says.

The North American country, however, had a higher rate of increase than Europe, according to the British study. According to the researchers, what could justify the most expressive value in the US would be the greater number of obese people in the country.

The study pointed out that the incidence of colorectal cancer had, in the USA, an annual percentage increase of 4.3% for people aged 20 to 29 years, 2.47% among those aged 30 to 39 years and 1.8% in people between 40 and 49 years old.

For Europe, the work used data from 1990 to 2016 from 20 countries on the continent to verify the incidence and mortality of colorectal cancer. The study points out that cases of the disease increased, from 2004 to 2016, 7.9% per year among people aged 20 to 29 years. For those between 30 and 39 years old, growth was, from 2005 to 2016, 4.9% per year. The group between 40 and 49 years old had an increase of 1.6% per year between 2004 and 2016.

The main symptoms of bowel cancer are blood in the stool, change in bowel habits, persistent abdominal pain and unintentional weight loss, says Jácome.

“What we have done in recent years is to raise awareness, in addition to the population, the medical class itself”, he says. “When a case of blood loss in the stool comes to the office in a 70-year-old, doctors often suspect cancer, but [com pacientes] at 30 years old they don’t suspect. This has led to delay in diagnosis.”

According to Paulo Hoff, the preventive exam can be done annually by analyzing fecal occult blood or by colonoscopy every 5 or 10 years. “The current recommendation in the world is that it be started at 50 years old. But, as we have seen this constant increase in incidence in younger people, there is a movement suggesting that this starting age should drop to 45”, he points out.