Colon and rectal cancer
Colorectal Cancer Increasingly Seen in Younger Adults
Millennials – those in generations born since 1980 – are being diagnosed more and more with a disease typically associated with aging.
Colorectal cancer (cancer of the colon and rectum) incidence rates are on the rise in young and middle-aged adults. And these diagnoses rates are on the increase in younger adults at the same time that they have been decreasing in people over the age of 55.
Scientists and the medical community have been trying to identify why this is happening. And a new study led by the American Cancer Society (Journal of the National Cancer Institute, February 2017) has provided some disturbing statistics.
Read about their findings here; and learn more about the symptoms of colorectal cancer as well as recommendations to reduce your risk.
What the research found
The study, led by Rebecca Siegel, MPH of the American Cancer Society, examined different age categories of some 500,000 people who had been diagnosed with colon or rectal cancer.
Researchers found that colon cancer incidence rates had increased at a higher percentage rate for those ages 20 to 39. For that age category the incidence rate had increased 1% to 2% each year over the period studied, compared to ages 40 to 54, where the incidence rate had only increased 0.5% to 1%.
And rectal cancer incident rates also increased at a higher percentage in ages 20 to 39 compared to older populations. For ages 20 to 39, the incidence rate had increased 3% per year over the period studied; while for ages 40 to 54, the incidence rate had increased only 2% per year.
The risk of colorectal cancer was reported to be:
- If born in 1990 the risk of colon cancer was five per million people, versus three per million for those born in 1950.
- If born in 1990 the risk of rectal cancer was four per million, versus 0.9 per million for those born in 1950.
- Three in ten rectal cancer diagnoses were found to now occur in patients younger than age 55.
Note that while the risk for colorectal cancer in younger adults was found to be increasing, it is still very uncommon for someone under 50 to be diagnosed with the disease. 90 % of new cases are still found in those over age 50. However, the upward trend in younger adults is alarming.
Also of concern is that this type of “aging” disease is likely not on the radar of young adults or their doctors. For this and the other reasons noted below, colorectal cancer is often diagnosed late in this age population, when the disease may have spread and worsened.
Colorectal cancer often diagnosed late in younger adults
The main reason attributed to the decline in colorectal cancers for older adults is simple: screening. The American Cancer Society and medical community advocate regular colorectal cancer screening starting at age 50.
Younger adults, however, have no recommended screening unless they fit specific criteria of either having had a history of bowel disease themselves or having family members with colorectal cancer or specific genetic markers.
Because the disease is still uncommon in young adults, it is not part of the usual checkup conversation of many doctors; nor is it typically considered as a diagnosis. And because a person having the disease may not show any symptoms, it is difficult for a doctor to diagnose colorectal cancer without screening. Cost may also be an issue. Younger adults may not have insurance, or their insurance may not cover the procedure given their age or lack of ongoing symptoms.
All of these factors result in younger adults being diagnosed later, perhaps when symptoms have gotten excessive. When the younger adults are finally diagnosed, the disease may be more advanced, requiring more extensive treatments. According to the American Cancer Society’s study, people under the age of 55 are 58% more likely to be diagnosed with late-stage colorectal cancer than older adults.
The Colon Cancer Alliance responded to the new research by echoing the concern over late and inadequate diagnoses, saying, “We hear over and over again that members of our community are being misdiagnosed by those same medical professionals – being told they are too young for a colonoscopy because they aren’t 50 years old. And by the time the cancer is found, months later, it is too late.”
What are the symptoms of colorectal cancer?
There are often no symptoms or they are vague digestive issues such as constipation or diarrhea, but there are some signs young people should be aware of.
- Blood in your stools or dark stools
- Rectal bleeding
- Narrower than normal stools (thin like a pencil)
- A change in bowel habit that lasts for more than a few days (diarrhea, constipation)
- Unexplained abdominal pain, cramping
- Unintended weight loss
- A feeling that you need to have a bowel movement even after you’ve already had one
- Weakness and fatigue
Note that these same symptoms can be caused by many other things including hemorrhoids, irritable bowel, inflammation, and other gastrointestinal issues.
Young people having a family history of colorectal cancer should talk with their doctors about their risk factor and potential screening. Note that while a family history may increase your risk, 85% of people diagnosed with colorectal cancer do not have a genetic link to it.
Can you reduce your risk?
Awareness, prevention, and early detection are the best defense.
Researchers do not know the precise cause of colorectal cancer. Most believe prevention is a combination of minimizing negative environmental exposures and optimizing healthy lifestyle factors such as diet and exercise. Obesity may play a role. While not proven to be a direct cause, researchers believe that the same poor lifestyle choices that increase one’s risk for obesity may also increase one’s risk for colorectal cancer.
Here are some general lifestyle guidelines recommended by the American Institute for Cancer Research: Talk with your doctor about what lifestyle changes may be helpful for you.
- Stay at a healthy weight and lose the belly fat – Excess body fat results in an increased risk of colorectal cancer. Note that a 2014 study (The Lancet) found a 10% increase in risk for colon cancer for every five-point increase in body mass index.
- Eat foods that fight cancer – Along with eating a healthy diet consisting of a lot of vegetables, cut back on your red meat and processed meat consumption. The AICR maintains information on various fruits, vegetables, spices, and other foods that have been identified as helping reduce one’s risk for diseases such as cancer. Blueberries, dark green leafy vegetables, garlic, and other food items are reviewed at http://www.aicr.org/foods-that-fight-cancer/. A Mediterranean diet may be preferred over a typical Western diet, and there is research currently underway to evaluate this. Calcium and Vitamin D are thought to be protective against colorectal cancer.
- Eat plenty of fiber – Eating high fiber foods promotes good bowel function and is associated with reduced risk for a variety of diseases such as diabetes, hypertension, and heart disease. It may reduce the risk for colorectal cancer although studies have conflicted findings as to that point.
- Be active – A sedentary lifestyle has been associated with greater risk for chronic disease.
- Stop smoking – Longtime smokers have greater risks.
- Show moderation with alcohol – Heavy drinking of alcohol appears to increase risk in men and may increase risk in women.
Experts also suggest young people know their family history
It is important for people to know their family medical history in regards to many different diseases, but particularly helpful to know if anyone in your immediate family has been diagnosed with colon or rectal cancer. If family members have had other colon issues, or precancerous polyps have been found during a colonoscopy, that is also good information to have. There are a few hereditary conditions, one called familial adenomatous polyposis (FAP) and another called hereditary non-polyposis colon cancer (HNPCC), that can increase your risk. 5-10% of people diagnosed with colorectal cancer have this type of inherited gene mutation
The best mode of prevention beyond awareness of possible symptoms is screening, and the best screening test is a colonoscopy.
This procedure can find and remove polyps found during the test. Polyps are growths that are found in the tissue lining of the colon or rectum. Colorectal cancer typically develops from a non-cancerous polyp. During a colonoscopy polyps can be removed, reducing the risk of the polyps turning cancerous. Your doctor will likely refer you to a gastroenterologist for the procedure.
The American Cancer Society’s recommendation is for screening starting at age 50. And while the society constantly reviews the incidence data and revises their policies, young adults today are not offered the screening on a routine basis. A colonoscopy is somewhat invasive and comes with minor risks. It is a substantial enough procedure that experts do not believe it could easily be made generally available.
There are other more limited tests, such as a fecal occult blood test (FOBT). This is a self-administered test that your doctor can give you to take home and later return a specimen for laboratory analysis. It can identify blood in the stool.
Researchers continue to work on other less invasive screening tests such as the relatively new Cologuard stool test. This is also a self-administered test that your doctor can give you to take home. The stool specimen is examined in a lab where blood can be identified but also, specific DNA markers for cancer can be found. With both the FOBT and the Cologuard test, any positive findings for cancer must be followed up with a colonoscopy for validation of diagnosis and to find and remove polyps.
For more information
The American Cancer Society – https://www.cancer.org/cancer/colon-rectal-cancer.html
American Gastroenterological Association – http://www.gastro.org/patient-care/conditions-diseases/colorectal-cancer
Colorectal Cancer Incidence Patterns in the United States, 1974–2013. Published February 28, 2017 in Journal of the National Cancer Institute. First author Rebecca L. Siegel, MPH, American Cancer Society, Atlanta.