Madrid, March 30, 2022- According to data published by the Spanish Society of Medical Oncology (SEOM), colorectal cancer will be the most frequently diagnosed cancer in Spain in 2022 with 43,370 new cases1. This type of cancer is a disease traditionally related to age - the vast majority of cases appear after the age of 50 - and one of the most preventable cancers thanks to early detection campaigns aimed at the general population of between 50-69 years of age, and based on performing screening tests.
"While in recent years we have seen how the incidence decreases or remains steady in those over 50, we are observing a significant increase in cases in younger patients (under 50)", warns Dr. Jose Ignacio Martin Valades, head of the Multidisciplinary Digestive Tumors and Peritoneal Oncology Unit at MD Anderson Cancer Center Madrid, who points out that these cases are "often in more advanced stages, with more aggressive histopathological characteristics and more comonly located in the rectum".
In a study published in Jama Surgery in 2015 by researchers from MD Anderson Cancer Center in Houston, they already warned of an increase in the annual incidence rate of colorectal cancer in young patients. Likewise, they estimated an increase in incidence in the US for 2030 in the population between 20-34 years of age of 90% for colon cancer and 124% for rectal cancer, and in the population between 35-49 years of 28% and 46%, respectively2. In addition, the magazine Gut published data in 2019 confirming that this trend is not exclusive to the US, but is also observed in other countries in Europe, North America and Oceania, in which this rebound in cases in young people began in the mid-903.
Another study published in the same year and in the same journal based on national data from twenty European countries also showed an increased incidence. Specifically, in the 40 to 45 age bracket, the incidence rate went from 15.5 per hundred thousand inhabitants in 2005 to 19.2 in 2016, which represents an annual increase of 1.6% between 2004 and 20164.
On the other hand, a study published in 2019 in the journal The Lancet shows an increase in the incidence of colon cancer in those under 50 years of 3.1% per year in Denmark, 2.9% per year in New Zealand and Australia and 1.8% per year in the United Kingdom5.
Regarding the most common symptoms that may lead us to suspect colon cancer, Dr. Martin Valades states that "we must be alert to the possible symptoms related to colorectal cancer and just because they appear in young patients, believe them to be less important", since, according to some studies, young patients with colorectal cancer who present symptoms may delay medical consultation for up to 6 months6.
In a systematic review of 55 studies that included a total of 6,425 patients under 40 years of age, it was concluded that the most common symptoms in this type of patient were: abdominal pain (55%), rectal bleeding (46%), weight loss (35%) and changes in bowel movements (32%)7. Other studies suggest that asymptomatic bleeding may precede other symptoms related to colorectal cancer by 2-3 years8.
“This lower awareness of symptoms in young patients, along with the lack of clinical suspicion and the fact that young patients are not included in early detection campaigns, could be related to a possible delay in diagnosis and, therefore, that this group of patients present tumors in more advanced stages”, warns the doctor. Despite these data, the 5-year colorectal cancer-specific survival rate is more favorable in young patients than in those over 509.
Factors that influence the appearance of colon cancer
The doctor maintains that further research into the exact causes of this increase in the incidence of colorectal cancer in young people is needed, since at the present time they are unknown, are probably multifactorial, and the fact that we see this trend in different countries and different races suggests a possible relationship with environmental factors.
One of the possible risk factors may be the adoption of unhealthy lifestyles like physical inactivity, a sedentary lifestyle, the consumption of sugary drinks and increased calorie intake which progressively leads to an energy imbalance and finally to the development of obesity. one of the best-known risk factors in the development of colorectal cancer10. Likewise, the specialist also points out the importance of not smoking and avoiding alcohol consumption.
Along with these recommendations, Dr. Martin Valades insists on the importance of carrying out screening tests on the general population that allow early detection of this tumor and, therefore, a greater probability of cure. As early as 2018, the American Cancer Society in the US recommended reducing the age of starting screening tests in the general population (without family history or predisposing diseases) to 45 years of age, with an open debate in different scientific societies in our country that advocate advancing this to 40.
Finally, Dr. Martin Valades states that the treatment of colorectal cancer in young people does not differ from that in older patients, but it is very important to address, from the moment diagnosis is made to long survivors, the psychosocial impact, quality of life and care of support in this group of patients with colorectal cancer; above all, in relation to anxiety or depression, job insecurity, problems with self-confidence (mainly in ostomy patients), sexual dysfunction and fertility problems.