“This is the gold standard for detecting colorectal cancer.”

He colorectal cancer It is one of the leading causes of death in Spain. However, its mortality rate can be significantly reduced by early diagnosis. This is reported by Dr. Maria José Safontmember of the board of directors of the Spanish Society of Medical Oncology (SEOM), in an interview with ConSalud.es, who assures that these initiatives not only make it possible to detect cancer in the initial stages, when it is most treatable, but also to prevent its development through identification and removal of precancerous polyps.

In Spain, participation in screening programs has improved in recent years, “but it is still below established targets,” the doctor points out. However, it is true that some Autonomous Communities have already systematically implemented these initiatives, where the current coverage 50% to 60% of the target population.

“There is a need to increase participation as it is estimated that higher participation rates could significantly reduce mortality from this type of cancer.”

However, “there is a need to increase participation because it is estimated that higher participation rates can significantly reduce mortality from this type of cancer,” he emphasizes. In fact, the disease has a “very favorable prognosis if detected in its early stages.” You can take part in these programs men and women from 50 to 69 years oldand “the goal is to reach 70% or more of this population to maximize the benefits of screening.”

In these programs fecal occult blood tests (SOB) They are a fundamental part. These tests look for traces of blood in the stool, which may indicate cancer or precancerous lesions. As the oncologist explains, “these are very sensitive techniques, although not very specific,” which means that a positive result must be confirmed by colonoscopy. In fact, this test is considered the “gold standard” for diagnosing colorectal cancer because “it allows direct visualization of the inside of the colon and the taking of a biopsy.” This is a preventative tool that allows “detect polyps at an early stage they can be removed before they develop into cancer.”

Despite advances in other techniques, none have been able to replace the effectiveness of colonoscopy in definitive diagnosis. CT colonographyfor example, provides three-dimensional images of the colon, but “has limitations in detecting polyps” and “requires confirmation with a follow-up colonoscopy to allow for biopsies,” the doctor says.

Besides, stool DNA testswhich analyze genetic fragments of a tumor are a less invasive advance, but “they will not completely replace the need for confirmation by colonoscopy in cases of suspicion.”

“They are not specific or sensitive enough to be used as a diagnostic test because their use is limited to monitoring colorectal cancer.”

Regarding the possibility of detecting colorectal cancer using blood tests, the specialist explains that there is currently no test of this type that combines the sensitivity and specificity required for routine use. Although some biomarkers such as carcinoembryonic antigen (CEA) may be elevated in patients with colorectal cancer, “they are not specific or sensitive enough to be used as a diagnostic test because their use is limited to colorectal cancer monitoring,” states the SEOM member.

In addition, in recent years there have been developments tests based on detecting tumor DNA in the bloodbut its implementation in clinical practice is still far from reality. “The key to early detection remains a combination of methods such as colonoscopy and stool occult blood tests,” the doctor emphasizes.

Colorectal cancer screening affects not only survival, but also the quality of life of patients. Removing polyps during a colonoscopy prevents the development of tumors. In addition, identifying the disease in the initial stages allows less aggressive treatment and reduces complications associated with advanced stages of cancer. All this, “combined with the adoption of healthy lifestyle habits,” is the key to reducing mortality, the expert concludes.