Gastroenterologist Dr. Alexander Marinov graduated from Medical University - Sofia and since 2015 has been working at the Gastroenterology Clinic of "Ajibadem City Clinic UMBAL Mladost". His interests are focused on oncological diseases, their prevention, diagnosis and treatment. He has a particular clinical interest in interventional gastroenterology and liver pathology.
We are talking to Dr. Marinov before World Colon Cancer Day about the prevention and treatment of this oncological disease.
Dr. Marinov, is the incidence of colon cancer increasing and what is the reason for this?
- Colon cancer is a dangerous and growing oncological disease. The age at diagnosis is also decreasing. On the one hand, this is due to the increase in risk factors for the disease, on the other, to the increasing awareness of patients and improved diagnostics in recent years.
Colon cancer is the third most common cancer in men after prostate cancer and lung cancer, and second in women after breast cancer. Each year, around 1.8 million people worldwide are diagnosed and 900,000 die. A colorectal cancer patient is diagnosed every 18 seconds.
What are the risk factors for colon cancer?
- A major risk factor is age – about 90% of patients are over 50 years old at diagnosis. The risk increases by 1.5% every 5 years after age 50. A diet high in animal fat is another risk factor. Red meat, high heat treatment and sausages are among the foods with the highest risk of developing colorectal cancer.
Animal fats stimulate bile secretion, the growth of anaerobic flora in the colon and the formation of secondary bile acids. Alcohol stimulates the formation of intestinal procarcinogens. A diet rich in fiber, fruits and vegetables lowers the risk of this disease.
Fiber, in turn, neutralizes the aforementioned bile acids and toxins and maintains an acidic pH in the colon. Low levels of vitamin D are thought to increase the risk of colon cancer. Increased physical activity reduces the risk by 40-50%.
People with obesity and diabetes as well as smokers are at higher risk. Chronic intestinal inflammatory diseases (ulcerative colitis and Crohn's disease) mainly affect patients at a young age and are an independent risk factor for colon cancer. Some colon polyps have malignant potential and often have no symptoms.
Undiagnosed and not removed in time, they can lead to the development of cancer. However, the disease develops as a result of a complex interaction between hereditary and environmental factors.
How can this oncological disease be prevented?
- The primary prevention of colon cancer is a change in lifestyle, limiting animal fats, alcohol and smoking. Fiber-rich foods and Mediterranean cuisine are beneficial. Secondary prevention is screening for those over 50, even 45.
Recently, it is believed that certain medications could reduce the risk of colorectal cancer. However, they must be strictly individualized and prescribed only by a doctor who evaluates all the benefits and risks of their intake.
What is the frequency of colon cancer screenings and at what age should they start?
- This depends on many factors - whether the patient has a relative with colon cancer, whether there are alarming symptoms, how long they last and at what age they appear. Methods of prevention are non-invasive and invasive, the first of which include periodic blood tests and stool diagnostics for occult (hidden) bleeding.
This screening should be carried out in all people after 45 years. It has high sensitivity, is inexpensive, and can be a starting point for whether to subject the patient to invasive colonoscopy
Patients with a direct relative with colon cancer should have their first screening colonoscopy 10 years earlier than their relative's age of diagnosis and even earlier if they have symptoms.
What symptoms should patients see a gastroenterologist for?
- Unfortunately, colon cancer has no early symptoms. Often, complaints appear at a late stage, when the chance of definitive treatment is low. In the beginning, the complaints are non-specific - bloating, malaise, pain. A change in the usual bowel habits, especially after the age of 50, as well as blood or mucus in the stools, should sharpen attention and patients should seek a specialist. There is often a feeling of lack of bowel movement, thinning stools, weight loss, easy fatigue.
Decreased hemoglobin values always require consultation with a specialist and conducting additional tests to exclude a cause from the gastrointestinal tract. Tumor markers are not routinely used for disease screening and diagnosis because they may be normal despite the presence of an advanced oncological process.
What are the colon cancer diagnosis methods and are they covered by the He alth Insurance Fund?
- The main method and gold standard for diagnosing colon cancer is colonoscopy. It establishes changes in the mucous membrane, enables the detection of polyps and their removal. Modern endoscopic equipment allows the disease to be detected in its earliest stages, when the patient has a chance for a complete cure. Patients fear that the examination is painful and unpleasant. But the procedure is performed with short-term anesthesia, it lasts about 20 minutes. Its conduct plays an essential role in the prevention of colon cancer.
What is the modern treatment of this carcinoma?
- After the diagnosis, there follows an equally important process of staging the disease, which is carried out with imaging methods - scanner and/or magnetic resonance. They help us understand how far the disease has progressed, whether it has involved lymph nodes or other organs, or whether it is limited to the wall of the large intestine. This information determines our subsequent therapeutic behavior.
It is extremely important that the treatment decision is made by an expert board with the participation of a medical oncologist, a gastroenterologist, a pathologist, an imaging specialist, a surgeon and a radiation therapist. Each patient is discussed separately, according to the localization of his disease, the stage, the accompanying diseases and the expected therapeutic response. An individualized approach to the treatment of each patient is extremely important for achieving optimal results, maximum duration and good quality of life.
Are modern therapies available for Bulgarian patients?
- Modern diagnostics and treatment for colon cancer are fully accessible to the Bulgarian patient. However, global standards and consensuses for prevention and treatment are not respected everywhere in our country. More funds should be directed to pre-hospital care, and there should be more workshops between experts and general practitioners to learn about new options and screening rules. The patient is not obliged to know if he has come to the right place and to interpret his symptoms himself, and it is the doctor's job to guide him correctly.
If priority measures are not taken regarding screening programs, financing of preventive packages, increasing the competencies of general practitioners and specialists, the he alth crisis will deepen. You cannot rely only on the conscience of patients that they will go to the doctor on time. Here, the role of information campaigns is to make people aware of the risks of diseases and the benefits of modern diagnostics.