It takes approximately 10 years for a small polyp to develop into cancer. Family history and genetics — Polyps and colon cancer tend to run in families, suggesting that genetic factors are important in their development.
Adenomas: Many colon polyps are the precancerous type, called adenomas. It can take seven to 10 or more years for an adenoma to evolve into cancer—if it ever does. Overall, only 5% of adenomas progress to cancer, but your individual risk is hard to predict.
A polyp can take as many as 10 to 15 years to develop into cancer. With screening, doctors can find and remove polyps before they have the chance to turn into cancer.
How long does it take for a polyp to turn into cancer? The growth and mutation of colon polyps into cancer is a slow process, taking an estimated 10 years on average. So as long as patients are screened, it is unlikely they will develop cancerous polyps.
Approximately 6% of colorectal cancers are diagnosed within 3 to 5 years after the patient received a colonoscopy, according to findings from a recent population-based study.
Colon cancer, or cancer that begins in the lower part of the digestive tract, usually forms from a collection of benign (noncancerous) cells called an adenomatous polyp. Most of these polyps will not become malignant (cancerous), but some can slowly turn into cancer over the course of about 10-15 years.
This means cancer and polyps can sometimes go undetected. So, despite having had a 'clear' colonoscopy, some patients go onto develop bowel cancer – referred to as post-colonoscopy colorectal cancer (PCCRC) or 'undetected cancer'.
In 1 to 7 years, depending on a variety of factors: The number, size and type of polyps removed; if you have a history of polyps in previous colonoscopy procedures; if you have certain genetic syndromes; or if you have a family history of colon cancer.
Polyps are common in American adults, and while many colon polyps are harmless, over time, some polyps could develop into colon cancer. While the majority of colon cancers start as polyps, only 5-10% of all polyps will become cancerous.
Most polyps are benign (not cancerous). Your doctor can tell if a colon polyp is cancerous during a colonoscopy by collecting tissue to biopsy. The results of the biopsy are typically sent to your doctor within a week. Only 5% to 10% of all polyps become cancerous.
The risk of polyps smaller than 5 millimeters (mm) being cancerous is very low. In larger polyps, the risk of cancer increases. Colon polyps grow very slowly and often do not cause symptoms. Regular colon cancer screenings can help detect them before they become cancerous.
In most cases, colon and rectal cancers grow slowly over many years. Most of those cancers start as a growth called a polyp.
Polyp Growth Rates
Cancerous polyps tend to grow slowly. It is estimated that the polyp dwell time, the time needed for a small adenoma to transform into a cancer, may be on average 10 years (17). Evidence from the heyday of barium enema examinations indicates that most polyps do not grow or grow very slowly (18).
Most colorectal cancers start as a growth on the inner lining of the colon or rectum. These growths are called polyps. Some types of polyps can change into cancer over time (usually many years), but not all polyps become cancer. The chance of a polyp turning into cancer depends on the type of polyp it is.
The cumulative recurrence rate of colon polyp was 13.8% within 1 year, and 60% within 3 years, while that of advanced polyps was 2.5% and 31% within 1 and 3 years, respectively.
In multivariable analysis, the presence of 5 or more polyps at index colonoscopy was found to be associated with the risk of metachronous HR-CRN (OR, 2.575, p = 0.049) after adjusting for risk factors, such as obesity, diabetes, and smoking.
Most people with colon polyps have no symptoms and don't know they have them. But if you have symptoms — like rectal bleeding, blood in your stools, or other bowel changes — you should see your provider.
Most polyps grow slowly and take from between 10 and 15 years to become cancerous.
Depending on their size and location in the colon, serrated polyps may become cancerous. Small, serrated polyps in the lower colon, also known as hyperplastic polyps, are rarely malignant. Larger serrated polyps, which are typically flat (sessile), difficult to detect and located in the upper colon, are precancerous.
A colonoscopy is the best way to diagnose and prevent bowel cancer. For most people it is a straightforward test. However, as with most medical tests, complications may occur. If you are at average or slightly above average risk of bowel cancer, screening every two years is recommended.
The doctor will then send any removed polyps to a pathologist for a biopsy to see if cancer is present. If the biopsy reveals that cancer is present, then cancer specialists will outline a treatment plan for the person. Common treatments for colon cancer include surgery, chemotherapy, and radiotherapy.
The effects of the sedation could last up to a day, so you should not drive or operate any machinery until the following day. You may feel gassy or bloated for a while after the procedure because of the air that was injected into your intestine during the colonoscopy.
A new study says colonoscopy offers at least ten years of protection against colon cancer mortality. Colon cancer is one of the most common causes of cancer death in the United States, but it is preventable with routine colon cancer screenings.
Screening for colorectal cancer
Colorectal cancer doesn't just appear suddenly. It starts as a small growth on your colon, called a polyp, which rarely causes symptoms. If left alone over many years, polyps can grow into cancer. The only way to know it's there is to look.
When colorectal cancer is found at an early stage before it has spread, the 5-year relative survival rate is about 90%. But only about 4 out of 10 colorectal cancers are found at this early stage. When cancer has spread outside the colon or rectum, survival rates are lower.