Colorectal cancer is the third most frequent cancer among non-skin cancer affecting all ethnic groups. Every year, approximately 1,5 million people are diagnosed with colorectal cancer and more than 500.000 of these people die. Risk of getting this disease for lifetime is %5 globally. Every year, approximately 140.000 people are diagnosed with colorectal cancer and more than 50.000 of these people die. In our country, every year 15.000 people are diagnosed with colorectal cancer and 7.400 people die.

There is an increased risk for people with colorectal cancer history or in their family. Similarly, there is an increased risk of developing colorectal cancer in people with breast, uterine or ovarian cancer, in the presence of colon polyps and people with Crohn’s Disease or Ulcerative Colitis.



Colorectal cancer rarely presents symptoms in early stages. Bowel cancer begins as a benign polyp. Colon polyps may or may not cause cancer. Colon polyps can be detected by screening tests and removed to prevent the development of colorectal cancer. In more than 90% of the cases, early stage cancers can be completely cured. Colorectal cancer is one of three cancers that can be screened worldwide, and colorectal cancers are a group of diseases that can be completely prevented by screening. If colorectal cancer has symptoms such as bleeding, changes in bowel habits, or abdominal pain, it usually means that cancer has progressed and is at an advanced stage. Unfortunately, less than half of the patients in this condition can fully recover.



Fecal occult blood test detects the blood that cannot be seen due to a colorectal polyp or cancer. If positive, colonoscopy is a must.

Colonoscopy is a technique used to evaluate large bowel and rectum, detect abnormalities, retrieve sample tissues or remote detected abnormal structure with the use of a long, flexible instrument. It is the most frequently recommended screening test since it is safe and effective. Because entire colon can be evaluated and colon cancer can be prevented by removing the polyps that may become cancerous. Colonoscopy is a golden standard diagnosis method for colorectal cancer screening.

Flexible sigmoidoscopy enables the physician to evaluate lower third of the large bowel, which is the part that has almost half of the polyp and cancer. If an anomaly is detected, colonoscopy will be required again.

Virtual colonoscopy is performed on the principle of reconstructing colonoscopy-like images by processing the images of air and coloring agent filled colon obtained by computed tomography. If anomalies are detected, colonoscopy will be required again. This examination should be applied if a complete colonoscopy cannot be performed.



Screening for patients without colorectal cancer risk factors should start at the age of 50. Having colonoscopy in every 10 years is the golden standard. Combination of flexible sigmoidoscopy in every 5 years and annual fecal occult blood test is an acceptable alternative in cases where colonoscopy is not suitable. Screening of patients who have colorectal cancer or polyps in their close relatives (mother, father or sibling) must start at the age of 40 or 10 years before the age of the youngest diagnosed relative. If the first colonoscopy is normal, these patients must undergo screening in every 5 years. Screenings of family members must be more frequent in familial colon cancer syndromes and screenings must start at an earlier age.



Individuals who have polyps detected that may turn into cancer must have colonoscopy every 3-5 years after polyps are completely removed depending on the type, number and size of the polyps. If a polyp is not completely removed by colonoscopy or surgery, another colonoscopy must be performed within 3-6 months.

Most colorectal cancer patients must have colonoscopy within a year of the first intervention. If the whole colon is not evaluated before the surgery, colonoscopy must be performed within 3-6 months. If this first follow-up colonoscopy findings are normal, colonoscopy should be repeated every 3-5 years.

In the presence of inflammatory intestinal diseases that increase colorectal cancer risk, colonoscopy and multiple biopsies must be repeated every 1-2 years in patients having persistent ulcerative colitis for more than 8 years or Crohn’s Disease patients.