Transcription
Today I'm going to go over the very subtle symptoms and signs of colon cancer that you should never ignore. Because colon cancer is one of those devastating cancers where on one hand, it's one of the most preventable cancers if you catch it early. But on the other hand, unfortunately, it's one of the more deadly cancers and it becomes incredibly hard to treat if you find it in later, more advanced stages.
And we have to talk about this and educate others because the rates of colon cancer are on the rise, especially among young people. And here's a worrisome trend: the number of cases of colorectal cancer in people under 55 have doubled over the past few decades. And colon cancer is becoming so prevalent in young people that, according to the National Cancer Institute, it's now the number one cause of cancer death in people between the ages of 20 to 49.
So to put that in perspective, the 5-year survival rate for localized colon cancer is 91%, but it drops all the way down to 13% once it spreads outside the colon and starts metastasizing to other organs. So recognizing the early symptoms could save lives, especially young people's lives, who historically did not have to worry about this awful cancer. So if you find this video helpful, share with your family and friends, as early detection is absolutely key in increasing your chances of surviving colon cancer.
Now, before we dive into the signs, let's quickly break down what colon cancer or colorectal cancer is. So colon cancer starts in the large intestine or the colon. And more often than not, this cancer begins as a benign, non-cancerous polyp. But some of those polyps can turn cancerous over time. And the good news is, if you catch these early, they can be easily removed, which is what happens during a routine screening colonoscopy. And I'm going to talk about the best screening methods later. But colon cancer is one of those few cancers where the screening and the treatment can be done at the same time.
Now, the first sign of colon cancer that we need to watch out for is any kind of change in your bowel habits. So if all of a sudden you start getting constipation, or you're having frequent loose stools or diarrhea, that could be one of the first signs of cancer. Now, having diarrhea or constipation for a week or two weeks can be fairly common and it's usually not a cause for major concern. But if that change in your bowel habits persists for longer than a few weeks, then it could indicate a more serious problem.
And the reason this happens is because the colon is responsible for absorbing water and forming stool. So any disruption in its function due to a tumor or a mass can manifest itself as chronic diarrhea or chronic constipation. So the reason colon cancer causes diarrhea is because the growth or the mass in the colon irritates the lining of the bowel, which will then increase the secretion of water and it will speed up the transit time of digestive materials, and that's what causes the diarrhea. And when it comes to constipation, that usually shows up if the tumor creates a physical blockage, which can slow down or prevent stool passage. And if you ever get alternating patterns of diarrhea and constipation, well, that could actually be a signal that cancer growth in the intestine is intermittently obstructing the colon.
Okay, the next sign we need to discuss is unexplained weight loss. And cancers in the colon lead to weight loss in two different ways. First, colon cancer can physically interfere with the proper nutrient absorption in the intestine. And second, many cancers, including colon cancer, cause weight loss because they divert the body's nutrients to support its own growth. And they do that by releasing all kinds of substances called cytokines that basically hijack the body's signaling and they redirect all of the nutrients to support their own proliferation and growth. So if you find that you're losing weight unintentionally and without a good reason, then I would definitely make sure to get evaluated for not just colon cancer, but other cancers as well.
So another subtle sign that could be an early warning symptom of colon cancer is blood in your stool. And the medical term for that is hematochezia. And blood in the stool is actually one of the hallmark signs of colon cancer. Now, having said that, the most common cause of blood in the stool are actually not related to colon cancer. And it's usually bleeding caused by hemorrhoids. And another fairly common reason for blood in the stool is a condition called diverticulosis, where you may develop small pouches or pockets inside the walls of your intestine. And those pouches can sometimes bleed or get infected. But anytime you do notice blood in your stool, or in the toilet, or on the toilet paper after wiping, you cannot assume that the bleeding is due to something like hemorrhoids. You need to get checked out to make sure you're not dealing with something more serious.
Next, another sign you have to watch out for is dark or black stools. Now, this dark color is also caused by bleeding. But the reason it appears black is because the source of bleeding typically originates somewhere in the upper digestive system, like the stomach or the small intestine. And as blood travels along the GI tract, it interacts with the digestive chemicals, which is what changes this color from red to black. But this dark blood can also come from the colon, and more specifically from the ascending colon, which is located on the right side of the abdomen. So yes, typically black stools usually point to an issue in our stomach, but in some cases, they can also come from a bleeding source in the colon, which needs to be evaluated for cancer.
Okay, and this brings me to another sign that should always be evaluated for colon cancer, and that is iron deficiency anemia. And the reason this happens is these cancers in the colon may not present with obvious or frank bleeding, like we just talked about. But it may cause a chronic or low-grade blood loss from a bleeding tumor. And eventually, the blood loss slowly depletes the body's iron reserves. And because it takes iron to build and replenish the hemoglobin in our blood cells, this constant turnover in the blood is what causes the iron deficiency, and that's what eventually leads to anemia.
Now, colon cancer is not the most common reason why people get iron deficiency anemia. And it's usually caused by inadequate iron intake or heavy menstrual periods or kidney disease. But if you were diagnosed with low iron and anemia, especially if you're a man, colon cancer definitely needs to be ruled out as a cause.
Now, another symptom that could point to colon cancer is a feeling of fullness after a bowel movement, or this feeling of incomplete evacuation. And the medical term for this is tenesmus, or this constant feeling like you have to go to the bathroom. And it's happening because as the cancer grows, especially if it's located in the lower colon or in the rectum, it can press on the bowel wall or it can mimic the sensation of stool remaining in the rectum. And this feeling or symptom is often mistaken for a common gastrointestinal issue like irritable bowel syndrome. But this could also be an early sign of cancer, especially if it persists for several weeks.
Okay, another symptom that needs to be evaluated if it persists for longer than a few weeks is excessive gas or bloating. And this gas and bloating happens due to several mechanisms. So if a cancer growth gets large enough, it can cause physical blockage in the colon, which can trap gas behind it, which in turn can lead to bloating and abdominal discomfort. And another mechanism for why this happens is these tumors can actually obstruct the normal digestion and fermentation of food in the colon, which eventually leads to the disruption of the balance of the bacteria in our gut. And anytime our gut bacteria or microbiome gets disrupted, it can lead to more gas and more bloating. And sometimes you get a situation where the partial blockages by the tumor will slow down the passage of waste in the colon, which will then give bacteria more time to ferment undigested food and lead to more gas production. So if you have persistent bloating and you haven't made any recent dietary changes, or if the bloating and the gas persists for longer than a few weeks, then that's a red flag and it definitely needs to be evaluated.
Now, let's talk about the most common early sign of colon cancer, and that is actually no sign at all, or an absence of clinical symptoms. And that is because colon cancer has to be pretty advanced before you start developing many of the signs to let us know there's a problem. And that is why it's so important to be very aggressive with your screening for colon cancer, because the best time to find it is when you don't have any symptoms at all. And the earlier you find it, the higher the chances of your survival.
So here in the US, the recommendation is to start your screening at the age of 45. And this is for people at an average risk of colon cancer. And the screening can be done either with a colonoscopy, or it can be done with a more non-invasive test like a stool test that you can do at home.
Now, with colonoscopies, it's a simple procedure in which a long flexible tube with a camera is inserted into the rectum. And your GI doctor will be able to examine your entire colon for any kind of polyps or any abnormal tissue. And if they do find any concerning polyps, they'll be able to remove those polyps right away and send them for biopsy. Now, colonoscopies are considered to be the gold standard for screening and diagnosing colon cancer. But there are a few disadvantages. So one, colonoscopies do require bowel preparation, which happens the day before the procedure, and that's not the most pleasant thing for most people. And there's also a very tiny risk of complications like bleeding or perforation during the procedure. And since colonoscopies in the US are usually done under sedation, there's also the tiny risk of complication from the sedation or the anesthetic itself.
So if you're not too excited about a colonoscopy, there are other alternatives you can discuss with your doctor. And those are your stool-based tests, like where you get a kit that will test your bowel movement for any blood, which could indicate possible colon cancer. And those tests are your fecal occult blood test or the fecal immunochemical test. And there are some stool tests that can check your bowel movement for any DNA changes that are concerning for colon cancer or large polyps.
Now, with these stool-based tests, the advantages are they're not invasive, so they don't require a procedure or sedation. But on the flip side, they're also not as good at detecting polyps or cancer precursors when compared to colonoscopy. And these tests have to be done anywhere from yearly to every three years, depending on the test you choose. So there are pros and cons to every test, but the most important thing is to get screened, no matter which test you choose.
And by the way, 45 years old is the absolute latest when we should start screening for colon cancer. And this is for people with an average risk of colon cancer. And in some cases, you need to start much earlier, at a much younger age. So if you have inflammatory bowel disease, like Crohn's or ulcerative colitis, then you'll need to start your screening earlier. Also, if you have a family member with a history of colon cancer, or if they have a history of high-risk polyps, then the recommendation is to start your screening at the age of 40, instead of 45, or 10 years before the age of relative was diagnosed, whichever comes first. So for example, if you have a relative that was diagnosed at age 35, then your screening will need to start 10 years before that, so as early as 25 years old.
Now, there's a little bit more nuance to that depending on what other risk factors you may have or what degree relative it is that was diagnosed with colon cancer. But your doctor will be able to guide you on the best test in your situation, or the best time to start your screening.
And by the way, as important as it is to talk about early signs of colon cancer so we can detect it early, probably the more important thing is to know how to prevent it. So stay tuned, as I'll be making another video in the future on the different causes of colon cancer in young people, and I'll talk about what steps you need to start taking to lower your risk of cancer. So subscribe and stay tuned for that. I hope this was helpful, and I'll see you in the next one.