david martínez sits at the center of a wider health shift: colon cancer screening is no longer only about finding disease early, but also about preventing it from progressing. That is the key message emerging from the current debate around colon cancer, which is marked each March 31 for World Colon Cancer Day and remains the tumor with the highest incidence in Spain.
What happens when screening is treated as prevention?
The Galician early detection program has been running for 13 years and has detected more than 2, 900 cases so far. It is aimed at people between 50 and 69 years old, who are invited to submit a small stool sample to check for microscopic blood. If the result is positive, the patient is referred for a colonoscopy to see whether there are lesions in the colon that may matter clinically.
The numbers show why the distinction matters. Around 6% of the tests performed to date have been positive, but a positive result does not automatically mean cancer. Out of every 100 patients with a positive test, only four will have colon cancer. The rest may have precursor lesions that can develop into a tumor over time. That is why the screening process is not just diagnostic: it can also remove lesions before they become cancer.
What if colonoscopy becomes faster and more accessible?
That is the logic behind a faster diagnostic pathway for patients with symptoms suggestive of colon cancer. In Málaga, a new circuit has been created to accelerate colonoscopy access for people with warning signs such as persistent changes in bowel habits, chronic anemia, rectal bleeding, or family history that raises clinical concern. The stated aim is to complete colonoscopy within a maximum of seven days from the request.
The practical steps are direct. Patients can activate the circuit themselves by phone, WhatsApp, or email, then receive an appointment within 24 hours for consultation, preoperative study, preanesthesia, informed consent, and colon preparation instructions. The colonoscopy is then carried out between Monday and Friday of the following week. If the exam is normal, no follow-up is needed. If low-suspicion polyps are removed, a telephone consultation follows within 15 days to discuss biopsy results.
What are the main forces reshaping this landscape?
The current direction is being shaped by four clear forces:
| Force | Impact |
|---|---|
| Earlier detection | Improves the chance of curative treatment and lowers the risk of recurrence. |
| Prevention through colonoscopy | Allows lesions that may become cancerous to be removed before they progress. |
| Faster access pathways | Reduces delays that can interfere with diagnosis when symptoms are already present. |
| Participation behavior | Participation in the Galician program rose to 56% in 2024, helped by sending the stool kit directly to homes, but many people still do not complete the test after receiving it. |
Clinical outcome data make the trend even clearer. When colon cancer is addressed in early stages, survival is 95%. In advanced stages, it can fall to 10% after five years. Early-stage disease also reduces the chance of recurrence. That gap is large enough to justify both broad screening and quicker symptom-based routes.
What if participation rises, but gaps remain?
Best case: more people complete screening after receiving the kit at home, positive tests are followed promptly by colonoscopy, and more lesions are removed before cancer develops. That would strengthen both prevention and survival.
Most likely: participation continues to improve gradually, while fast-track colonoscopy pathways expand for symptomatic patients. The system becomes more efficient, but uptake still depends on sustained reminders from primary care, hospital care, and nursing teams.
Most challenging: kits continue to be set aside, symptoms are ignored, and delays persist between suspicion and diagnosis. In that scenario, the same disease burden remains harder to shift even though the tools already exist.
Who wins, who loses?
Patients gain the most when screening is completed and symptoms are acted on early. Those with precursor lesions may avoid cancer altogether. Those diagnosed early have a far better chance of cure, often without chemotherapy.
Healthcare teams also benefit from clearer pathways, because faster diagnosis can reduce the uncertainty around suspicious symptoms. The main losers are the people who delay action, either by not completing the screening kit or by waiting too long after symptoms appear. In colon cancer, time remains the decisive variable.
For readers, the message is straightforward: the system is moving toward earlier action, quicker colonoscopy access, and stronger prevention. The opportunity is real, but it depends on participation, prompt referral, and using the available pathways before disease advances. david martínez
