Colonoscopy and the test for occult bleeding in stool allow early detection of lesions that could become a tumor.
Although age is the main risk factor for colorectal cancer, since 90% occurs in people over 50 years of age, in recent times it has been seen that it is increasingly being diagnosed in people under that age, which has caused concern. Because of this, some international scientific societies have begun to recommend preventive check-ups starting at age 45 in patients without symptoms or a family history of colorectal cancer.
This is evidenced by a study published by the American Cancer Society, which reveals that, in the United States, diagnoses of people under 55 years of age increased from 11% in 1995 to 20% in 2019. They also highlight the concern not only for the increase in cases but, above all, because of the speed with which it has increased.
In this regard, the Dr Ricardo Silva, an oncologist at the Cancer Center of Clínica Universidad de los Andes, maintains that more than a decade ago, this cancer at an early age represented 4.8 and 9.5% of colon and rectal cancers, respectively. Epidemiological evidence documents that, since 1994, the incidence in people under 55 years of age has increased 2% per year, especially in the population between 20 and 35 years of age. Thus, it is projected that, by 2030 in the US, 10% of colon cancers and 22% of rectal cancers will be diagnosed in people under 50 years of age.
“Given this new scenario, the American Society of Oncology (ASCO) has advanced the age for early detection screening to 45 years. The origin of this higher incidence is not completely clear and from the clinical point of view, colorectal tumors in young patients are more distal in location and present in more advanced stages at diagnosis. In Chile, the etiology of these epidemiological changes is not clear either, forcing us to promote education in early screening, genetic counseling in cases with high family penetrance, promote healthy lifestyles, improve our records, and promote the research in reference centers like ours in order to reduce the incidence and mortality associated with this disease”, explains Dr. Silva.
Risk factors for colon cancer
The main risk factors for colorectal cancer are:
- Being over 45 years old
- Having a personal or family history of this pathology or colorectal polyps
- Having inflammatory bowel disease, such as Crohn’s disease or ulcerative colitis
- Suffering from hereditary non-polypous colorectal cancer (Lynch syndrome)
- Having familial adenomatous polyposis
- smoking
- Overweight and obesity
- Sedentary lifestyle
- Diet low in fiber, fruits and vegetables, and high in fatty or processed foods
Diagnosis of colorectal cancer
The mucosa that lines the interior of the colon and rectum can develop lesions over time, such as polyps that, although they are usually benign, can transform into a cancerous tumor. In order to detect them in time and thus obtain good results, it is advisable to carry out screening tests that indicate their presence.
In this regard, the Dr. Felipe Quezadacolorectal surgeon PRE-COLON program from Clínica Universidad de los Andes, explains that one of these tests is the test for occult bleeding in stools (Colon Test), a simple and non-invasive study that does not require prior preparation. It is taken at home and then the sample is taken to the Clinic.
The objective of this test is to detect non-visible blood in the stool. If there is no blood in the stool, it is indicated to repeat it annually. However, if it were positive, the presence of polyps and/or other conditions in the colon would be suspected, for which reason a colonoscopy would be required, an examination in which, using a colonoscope (tube probe with a camera), it is possible to visualize and study the entire path of the lower digestive tract, from the colon to the rectum. In addition, it is possible to take samples for biopsy examinations.
“If a malignant lesion is found, depending on its characteristics it can be removed during the same colonoscopy or determine, if necessary, surgery. In case of early treatment of these lesions by colonoscopy or surgery, the possibility of cure is very high (over 90-95%) and without the need for other treatments such as chemotherapy”, assures Dr. Quezada.
The occult stool bleeding test is aimed at people between the ages of 40 and 75 who do not have:
- Gastrointestinal symptoms
- Personal history of colorectal cancer
- First-degree family history (parents, siblings, and children) of colorectal cancer
For those who meet these requirements, this test is recommended. Likewise, people who require it can enroll in the Program for the early detection of colorectal cancer, PRE-COLON, whose objective is to early detect both polyps and cancers of colorectal origin.
