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).
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.
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.
If the colonoscopy finds one or two small polyps (5 mm in diameter or smaller), you are considered at relatively low risk. Most people will not have to return for a follow-up colonoscopy for at least five years, and possibly longer.
Smoking, obesity, diabetes, and inadequate exercise are risk factors for polyps, but many people with none of these risk factors have precancerous polyps in the colon. There are genetic risk factors for developing polyps as well.
Colon polyp development involves genetic and epigenetic changes and environmental effectors such as stress in this process can drive the normal colonic epithelial cells to hyperplastic and adenomas [25-27].
The size of a polyp typically does make a difference. The larger the polyp becomes, the bigger the risk of it developing into colon cancer. That risk increases significantly if the polyp is greater than 10 mm (1 cm); research has shown the larger a colon polyp becomes, the more rapidly it grows.
Most colon polyps are harmless. But over time, some colon polyps can develop into colon cancer. Colon cancer can be fatal when found in its later stages. Anyone can develop colon polyps.
A gastroenterologist, the specialist who usually performs a colonoscopy, can't tell for certain if a colon polyp is precancerous or cancerous until it's removed and examined under a microscope.
But some colon cancers may start as polyps. So, the more polyps you have, the higher your cancer risk. Someone with just one or two small polyps is generally at lower risk of having or developing colon cancer than someone with three to nine, or more.
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'.
If a polyp is removed or a sample of the colon lining is removed (a colonic biopsy), it may take a few days (or more) to find out that cancer, an adenoma or another finding was discovered.
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).
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.
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.
Cancerous polyps may cause no symptoms at all. But if you do have symptoms, they depend on where the polyp is located: Colorectal polyps may cause belly pain, constipation, diarrhea or blood in your poop. Stomach polyps may cause nausea, belly pain, vomiting and bleeding.
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.
Most colorectal cancers start as colon polyps, abnormal growths in the wall of the colon. Some polyps can develop into cancer if left untreated for a long time (usually at least 10 years). Screening is crucial for cancer detection because most colorectal cancers don't cause symptoms in the early stages.
Colonoscopic polypectomy is the best diagnostic and therapeutic tool to detect and prevent colorectal neoplasms. However, previous studies have reported that 17% to 28% of colorectal polyps are missed during colonoscopy.
Colorectal cancer can occur without polyps, but it is thought to be an uncommon event. Individuals with long-standing inflammatory bowel diseases, such as chronic ulcerative colitis and Crohn's colitis, are at increased risk for developing colorectal cancer that occurs in the absence of obvious polyps.
Approximately 1% of polyps with a diameter less than 1 centimeter (cm) are cancerous. More than one polyp or a polyp that is 1 cm or bigger places you at higher risk for colon cancer. Up to 50% of polyps greater than 2 cm (about the diameter of a nickel) are cancerous.
It's estimated that it takes about 10 years for cancer to form into a colorectal polyp.