Knowledge is power.
Patients with IBD have higher cancer risk than the general population -- sometimes massively higher risk.
Cancer risk in IBD increases
significantly with disease
duration, extent, and severity.
Many IBD patients are not aware of their
personal cancer risk, how it changes over time,
and how to manage it as proactively as they
manage their IBD.
EDUCATION
Five Fast Facts: IBD & Cancer
Colon cancer is the second-leading cause of cancer-related death in the United States. It is the leading cause of cancer-related death for IBD patients, who are at increased risk.
Colon cancer is usually fatal if detected late, but it is highly treatable if detected early. Symptoms do not tend to develop early, which makes surveillance so important.
The highest risk patients have extensive disease and active inflammation. But they are not the only patients with risk. Even patients with limited disease that is well-controlled by medication have cancer risk.
Cancer risk steadily increases over time. It increases by large jumps if dysplasia is detected or if a new abnormality develops, such as a stricture.
The safest patients manage their cancer risk with the same determination that they manage their IBD. The key elements are getting the inflammation under control and regular colonoscopy surveillance.
Know Your Risk
Not all IBD is created equal -- and neither is IBD cancer risk.
Cancer risk changes dynamically over time, suggesting a need for more or less monitoring or intervention.
The first step is to understand your own risk and how it is evolving
Risk vs. Luck
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Two things determine the likelihood of an IBD patient developing colon cancer:
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Patient-specific risk factors
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Luck
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Patient-specific risk factors are things about you and your disease that increase or decrease the risk of cancer. Most famously, smokers develop a lot more lung cancer than non-smokers because smoking introduces cancer-causing agents (carcinogens) directly into lung tissue. The same is true for exposure to radiation or toxic chemicals.
Luck refers to the part of cancer that is based on random processes. For cancer to develop many different events have to occur. While patient-specific risk factors increase the likelihood of those events happening, they won't happen to everyone. Luck is the reason some smokers never develop lung cancer while some non-smokers do.
Your Individual Cancer Risk​
And How It Changes
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The most frequently cited statistic is 2% risk of cancer after 10 years of symptoms, 8% after 20 years, and 18% after 30 years.
But these are just averages. They don't reflect any one individual because they blend together many people with very different risk profiles.
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To get closer to an idea of personal risk, we look at patient-specific factors:
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IBD Severity
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IBD Duration
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IBD Extent
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Chronic Tissue Damage
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Dysplasia​
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Stricture
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Shortened/Tubular Colon
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Post-Inflammatory Polyps
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Non-IBD Risk Enhancers
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PSC​
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Genetic Cancer Syndromes
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Family History
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Age
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IBD Severity
Active inflammation causes cancer-initiating damage to the colon. Just as the occasional social smoker has less damage to their lungs than the pack a day smoker, a patient with mild, generally inactive colitis has less cancer-causing colon damage than someone with colitis that is frequently active and non-responsive to medication.
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IBD Duration
The damage caused by inflammation is cumulative: as long as inflammation is present, the damage continues to pile up. The longer a patient has had IBD, the greater the amount of time the colon has been exposed to cancer-causing inflammation. A pack a day for ten years carries less cancer risk than a pack a day for twenty years.
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IBD Extent
People with pancolitis are at significantly higher cancer risk than people with colitis limited to the left side. Similarly, people with left-sided colitis are at significantly higher risk than people with colitis limited to the rectum.
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Chronic Tissue Damage
Nothing changes likely cancer risk more dramatically than new findings of tissue damage caused by IBD. This includes:
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Dysplasia (any form, including indefinite)
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Stricture (particularly in ulcerative colitis)
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Shortened / tubular colon
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Post-inflammatory polyps
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Non-IBD Risk Enhancers
There are a variety of patient-specific factors that increase cancer risk independent of IBD. Most notably:
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Primary Sclerosing Cholangitis -- PSC causes inflammation of the bile ducts. Only a small fraction of people with IBD have PSC, but the majority of people with PSC have IBD.
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Genetic Syndromes Associated with Colon Cancer -- Genetic syndromes include familiar adenomatous polyposis (FAP), hereditary nonpolyposis colon cancer (HNPCC or Lynch syndrome), and Li-Fraumeni syndrome.
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Family History of Colon Cancer -- An individual's risk of colon cancer is greater if they have a first-degree relative (parent, sibling, or child) who has had colon cancer. The risk is even greater if the first-degree relative had early onset colon cancer.
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Age -- Age is a general risk factor for increased cancer risk.
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Manage Your Risk
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In IBD, the highest risk patients have extensive disease and active inflammation, but even patients with limited disease that is generally well-controlled also develop IBD-related cancer.
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The actions you take directly affect the likelihood you will develop cancer. Reducing IBD-specific cancer risk has two crucial components:
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Inflammation control
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Regular colonoscopies​
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In addition, people with IBD can manage their overall cancer risk by following the same healthy living recommendations that apply to everyone.
Real Talk About Colonoscopies
Regular colonoscopies are a minimal inconvenience... and they just might save you from a fatal disease.​
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Here are three important things to keep in mind about the benefits -- and the limits -- of colonoscopies:
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IBD patients who follow surveillance guidelines live longer
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Good bowel prep makes a great difference
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Expert endoscopists are more effective
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IBD Patients Who Follow Surveillance Live Longer
Most people with IBD will not develop colon cancer, but many will. Those who follow surveillance schedules faithfully are more likely to have a pre-cancer removed (often without surgery) than patients who do not undergo surveillance. Among patients who develop colon cancer, those who undergo regular surveillance have it detected at an earlier stage and have a higher survival rate.
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Good Bowel Prep Makes a Great Difference
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Pre-cancer in IBD comes in a wide variety of shapes, sizes, and appearances. It is often flat or understated. Moreover, it must be detected in a background of inflammation, scarring, or other IBD-related anomalies. High-quality prep increases the odds that difficult-to-detect pre-cancer or cancer will be found and removed. It is particularly important to take steps ahead of the exam to:
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Have a clean bowel
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Minimize visibility-reducing inflammation via medication if necessary
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Expert Endoscopists Are More Effective
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Because cancer surveillance in IBD is more difficult than in non-IBD patients it requires a high level of skill. An expert endoscopist will have extensive experience in doing cancer surveillance for IBD patients.
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They will also:
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Have a high adenoma detection rate, which is a measure of effectiveness at detecting abnormalities (the national benchmark is 25% for men and 15% for women)
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Will reach the cecum (the far end of the colon near the small intestine) in at least 95% of exams, which ensure full coverage of the colon
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Complete a thorough exam, both in and out, to ensure thoroughness in studying the surface of the colon (withdrawal time of at least 15 minutes)
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Provide a written report that clearly documents findings including:
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Photos of all parts of the colon​
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Comments on bowel preparation
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Times on how long it took to insert and withdraw the endoscope
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Description of examination behind colon folds
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Description of inflammation in locations along the colon as well as identification of chronic features (scarring, post-inflammatory polyps, stricture, etc)
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Use chromoendoscopy (the gold standard for dysplasia detection) or have another provider to refer you to for a follow up exam should there be any abnormal findings
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Take targeted biopsies looking for abnormal tissue, but also take random biopsies -- at an absolutely minimum every 10 centimeters and more around areas of concern -- in patients with higher risk presentation.
Dysplasia: What's Next?
A finding of dysplasia represents a major change in patient cancer risk rivaled only by the development of a new stricture, shortened/tubular colon, or a new diagnosis of PSC.
While most patients with indefinite or low grade dysplasia do not progress to high grade dysplasia or cancer, many do progress. Some patients who have their first ever finding of dysplasia will already be harboring a cancer that has not been detected.
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Many factors affect progression from dysplasia that must be discussed extensively with your healthcare provider.
Our scientific collaborators developed a cancer risk estimator after a finding of low grade dysplasia, available here. ​
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Colon Cancer Warning Signs
In IBD, cancer symptoms often overlap with IBD flare up symptoms, causing some patients to miss warning signs.
The appearance of any of the warning signs described below merits an immediate conversation with your healthcare provider. This is particularly the case if you are having flare-like symptoms that seem in different, worse, or more persistent than usual.
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Changes in the size, consistency of frequency of bowel movements
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Narrower stools, loose stools or diarrhea
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Constipation
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Significantly higher or lower frequency of bowel movements
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Rectal bleeding or blood in the stool (bright red or very dark)
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Abdominal cramps, bloating, gas pains, or inability to pass gas
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Unusual fullness or feeling that the bowel does not empty completely
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Rapid or unintended weight loss
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Feeling constantly weak or tired
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Anemia
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Vomiting
