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Signs You Have Colorectal Cancer, According to Oncologist

Everything to know about colorectal cancer.
FACT CHECKED BY Emilia Paluszek

Cases of colorectal cancer are increasing and the American Cancer Society estimates there will be 106,180 new cases of colon cancer.44,850 new cases of rectal cancer this year, making colorectal cancer the third most common cancer for both men and women in the United States and the third leading cause of death that's cancer related. The Centers for Disease Control and Prevention defines colorectal cancer as "a disease in which cells in the colon or rectum grow out of control. Sometimes it is called colon cancer, for short. The colon is the large intestine or large bowel. The rectum is the passageway that connects the colon to the anus. Sometimes abnormal growths, called polyps, form in the colon or rectum. Over time, some polyps may turn into cancer." Eat This, Not That! Health spoke with Dr. Fernando De Zarraga, a medical oncologist/hematologist at Miami Cancer Institute, part of Baptist Health South Florida, who explained what the signs of colorectal cancer are to watch out for and who is at risk. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Rectal Bleeding or Blood in Your Stool

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According to Dr. Zarraga, "Anytime one sees blood in their stools or blood emerging from the rectum, this is abnormal. Oftentimes we assume that this is something as simple as a hemorrhoid and, while it might be one, we should never assume that it is as it could be a sign of something far more serious. If you see or note rectal bleeding or blood in your stool, you should seek medical attention immediately."


A Feeling That Your Bowel Doesn't Empty Completely

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Shutterstock / Taras Mikhailyuk

Dr. Zarraga states, "One of the things that we ask patients when we're getting a medical history is whether there's been any change in their bowel habits. This is because oftentimes when someone develops a tumor in their gastrointestinal tract, it in fact changes how their bowels function. Patients can become constipated or feel that their bowel doesn't empty completely. This is because there is a tumor that is interfering with the normal function of one's bowels. Therefore, a change in bowel habits warrants medical attention."


Who is at Risk for Colorectal Cancer


Dr. Zarraga says, "There are several risk factors for developing colorectal cancer. Among them are age, diet and lifestyle changes, race, and hereditary syndromes. As a result of all of these conditions, the American Cancer Society has recommended beginning to screen for colorectal cancer at the age of 45 for patients with what is considered average risk, that is those who do not have a personal history of colorectal cancer or certain types of polyps, a family history of colorectal cancer, a personal history of inflammatory bowel disease (ulcerative colitis or Crohn's disease), a confirmed or suspected hereditary colorectal cancer syndrome, such as familial adenomatous polyposis (FAP) or Lynch syndrome (hereditary non-polyposis colon cancer or HNPCC). African Americans are about 20% more likely to get colorectal cancer and about 40% more likely to die from it than most other groups. This is thought to reflect differences in risk factors (diet, genetics, lifestyle) and in health care access, both of which are related to socioeconomic status."


Why are More Cases of Colorectal Cancer Happening?

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Dr. Zarraga explains, "While the incidence of colorectal cancer is certainly increasing, it remains unclear exactly why. Some of it may be because more and more people are getting the appropriate screening tests. With more people getting appropriate screening, the number of cases of colorectal cancer certainly increases. The increasing incidence of colorectal cancer happening in younger patients, however, is something that is unexplained and likely attributable to diet, lifestyle changes, or other environmental changes."


What Causes Colorectal Cancer?

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"It's unclear exactly what causes colorectal cancer, however, cancer in general usually develops as a result of uncorrected errors in one's DNA," says Dr. Zarraga. "There are certainly genetic abnormalities that predispose one to these errors and therefore increase the risk of developing cancer in general. Colorectal cancer specifically has historically been felt to arise from polyps, underscoring the importance of appropriate screening at the appropriate intervals."

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What's the Survival Rate for Colorectal Cancer

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Dr. Zarraga states, "Through information obtained from the SEER database, we know that the 5-year survival rate of colorectal cancer can range from 91% in patients with localized disease to 14% in those with distant metastasis."

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How Can You Lower Your Risk of Colorectal Cancer?

stop smoking

"Probably the most important and significant way of lowering your risk of developing colorectal cancer is to be screened for it," Dr. Zarraga reminds us. "The American Cancer Society recommends beginning screening at the age of 45 for patients with average risk of developing colorectal cancer. Therefore, undergoing the appropriate testing presents one with the best opportunities to lower the risk of developing eventual cancer. Other ways of lowering your risk of colorectal cancer include eating a diet rich in fruits and vegetables, exercising, managing one's weight, and avoiding the use of alcohol and tobacco products."

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Colorectal Cancer Can Be Treated and Cured if Caught Early

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"Colorectal cancer is one of the more common cancers and fortunately it is also one of the cancers where we have a very effective way of screening for it. We talked about colonoscopies beginning at the age of 45 for average risk patients and this is certainly a good start. There are also a number of stool based tests as well that could be of help in someone who is unable to have a colonoscopy, but the important thing is to be proactive and seek medical attention for any complaints. This is a very treatable disease and curable. Because African Americans are 20% more likely to get colorectal cancer than other groups, and because the incidence in this group is skewing increasingly younger, it is extremely important that African Americans get screened for colorectal cancer as soon as it is appropriate."

Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather
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