Okay, so large intestine and GI bleeding. So colorectal cancer, very timely, it is colorectal cancer awareness month, basically describes a cancer that is located anywhere in the colon or the rectum, and colon cancer is one of the most common cancers in America, with a lifetime risk of about 5%. So the natural history of colon cancer starts from our polyps, which we talked about before. So these are small polyps here, these are adenomas, so adenomas are the types of polyps that have the potential to develop precancerous features if left in the colon. So a small polyp can develop into a larger one, and then we have this larger polyp that's then developing these dysplastic changes, which is that precancerous transformation, which can then develop into a full-blown adenocarcinoma. This is here an adenocarcinoma that looks like it's mostly confined to the actual polyp, and then this can become invasive. So this kind of process from polyp to cancer usually takes about 10 years, I guess sometimes 15, but that's where our colonoscopy screening intervals usually come from. So clinical presentation of colon cancer, many people are asymptomatic. That's why we have screening protocols where we are screening all comers once they reach a certain age. Other individuals may have some signs or symptoms that are concerning, things like changes in bowel habits, rectal bleeding, unintentional weight loss, new iron deficiency anemia. And some people present fairly advanced with signs or symptoms concerning for obstruction or maybe peritonitis. So as far as screening goes, the most current guidelines are advocating for screening of all average risk individuals starting at age 45. For everybody else on this list, so individuals with a family history of colon cancer or an inherited colorectal cancer syndrome like Lynch syndrome or known inflammatory bowel disease, it becomes a little bit more individualized, and we usually start well before age 45. But if someone's just average risk, no personal or family history to put them at increased risk for colon cancer, we start at 45. Many options for screening. So there are some stool-based tests, which are the first three things here. There is the fecal occult blood test, which basically looks for microscopic amounts of blood in the stool. That needs to be repeated usually every year. The fecal immunohistochemical test is a FIT test, which is also a stool-based test, also looking for microscopic amounts of blood, and also there's a specific test that they do to see if there's blood that we can't see in someone's stool. That also needs to be repeated every one to two years. The ColoGuard, which I'm sure many have heard about either personally or seen advertisements for, is this multi-targeted stool DNA test. If somebody has a negative ColoGuard test, that needs to be repeated every three years. Flexible sigmoidoscopy is an endoscopic procedure where we look at basically the left side of the colon only. So that looks at the rectum and the sigmoid colon and probably a little bit of the descending colon. So you usually get a good view of maybe 30% of the colon with the FlexSig. That needs to be repeated every five years. Then we have colonoscopy, which is probably the most common way that most people get their colonoscopy screening, and then CT colonography for individuals who maybe aren't a great candidate for colonoscopy or don't want to get a colonoscopy, which is basically a fancy CT scan. You still have to do a prep for the CT colonography, though. These are all very scary pictures that we never like to see. So these are all just different pictures of colon cancer. That's kind of all this is. So in terms of treatment, the first thing that you want to do when you have a new cancer diagnosis is disease staging. So as long as the disease is confined to the colon, then individuals are candidates for resection, which is usually a segmental resection of the colon. So for example, this schematic is looking at someone who has a tumor in the sigmoid portion of the colon. And so that individual would actually get most of their sigmoid colon removed here and then reconnected. So they would just get a sigmoid colectomy, and they actually do very well. If unfortunately the tumor has involved either local organs or the lymph nodes or things like this. So if it's metastasized to places other than the colon, then there's a role for chemotherapy and depending on how advanced things are, palliative care. So lower GI bleeding usually originates beyond the ligament of trites. We talked about that as the anatomic border when we were talking about upper GI bleeding. So the majority of GI bleeds that we do see are coming from the colon. So symptoms of lower GI bleeding, hematochezia, which is just frank, bright red blood that's coming out of the rectum, melana or those black, tarry stools, which usually suggest something that is a little bit more proximal. So maybe a right-sided bleed in the ascending colon or maybe something in the small bowel. Some patients will present with symptomatic anemia. So they will go to their primary care doctor or show up at the ER and they'll have a hemoglobin of five when it should be 14 or something like this, and they are definitely feeling it. They are short of breath. They are not really able to do much in terms of activity that they used to be able to do. Maybe they've passed out. Maybe they have some lightheadedness. Some individuals, depending on how anemic they are and how quickly they got there, may also present with chest pain. So lots of different things that can cause GI bleeding. Probably the most common one that we see are diverticular bleeds. So diverticulosis, I think we're going to actually talk about this a little bit more. So diverticulosis is a very common cause. Again, we have angio-dysplasia, which are these abnormal-looking blood vessels, which can bleed quite a bit. You can see them both in the upper and lower GI tract and in the small bowel. Ischemic colitis, which is fortunately not quite as serious as mesenteric ischemia, but is still a pretty significant disease process nonetheless, which is basically there's compromised blood flow to certain areas of the colon. Hemorrhoids, which are these engorged blood vessels that you can see in the rectum, colon cancer, or other malignancies. This is inflammatory bowel disease that looks very angry. This here is actually infectious colitis. So these little bumps here are called pseudomembranes. So this is probably, or this is a patient with C. difficulitis. And sometimes people might bleed because we did something to them that made them bleed. So individuals who've had a recent colonoscopy, if there was a large polyp that was removed, sometimes those individuals may come back either several hours to several days later with a post-polypectomy bleed from that polyp resection site. So management of lower GI bleeds, similar to upper GI bleeds. We need IV access. We need the IVs to be fairly large. We're going to start with volume resuscitation with fluids. And if somebody is sufficiently anemic, then they are candidates for blood transfusions as well. Management, especially depending if somebody is showing up and they look very sick. So if they have the symptomatic anemia, if their hemoglobin is much lower than you would expect based on how their symptoms are, you want to rule out a very, very brisk upper GI bleed. And so we do that with an upper endoscopy. If that is negative, then we can go on to our colonoscopy. NG lavage is basically a procedure where one gets an NG tube. So that tube that goes in through the nose, it's in the back of the throat, and the tip ends in the stomach. You can then use like a syringe to put a whole lot of water or saline into the stomach. And then you kind of draw things back. And if there's bloody aspirate on your NG lavage, that is a nice tool to kind of let you know that maybe you need to check the upper scope before you do a colonoscopy. So these are a couple of different ways that we will try to achieve hemostasis or stop bleeding in a lower GI bleed. So these first two here, these first two photos, sorry, are a patient who had a colonoscopy. There used to be a polyp here. That polyp was removed. And now you see there's some blood that is accumulating there. So this is a post polypectomy bleed, which is managed nicely with the placement of some hemostatic clips. The bleeding diverticulum, this is like the white whale of gastroenterology. A lot of our GI bleeds, our lower GI bleeds, are related to diverticula. But the chances that you'll actually see one that's actively bleeding by the time the patient comes in, by the time the GI consult's called, by the time the patient is able to complete a bowel prep, most of these usually will resolve on their own. So to find one that is still actively bleeding and to be able to do something about it does not happen often. I think I've seen one. But it's very satisfying to see this and then be able to kind of put clips on it and stop it. So also another post polypectomy bleed up here, this one is managed with injection with the scleral needle of epinephrine. Hemorrhoids of those are causing symptomatic bleeding. Similar to the esophageal varices, you actually use the same bander, you can place some rubber bands over a hemorrhoid, which will kind of decompress that entire column of vessels. And that is a way to treat hemorrhoids that are either symptomatic or that are bleeding. Angiodysplasia, those are the bleeding lesions that you can kind of see anywhere in the GI tract, really. But they are very superficial lesions. Still, I will never learn, I'm sorry. Very superficial lesions, and so those actually respond very nicely to APC, which is the thermal therapy that we use that doesn't actually touch the lesion. Similar to radiation proctitis in individuals who have had maybe prostate cancer or some sort of gynecologic cancer and have received radiation to the pelvis in the past. Diverticulosis. So diverticula are basically these outpouchings of the colonic mucosa and submucosa. Most people aren't born with this. They are an acquired lesion. The incidence increases with age. I think maybe like 50% of people who are undergoing screening colonoscopy, so age 45, 50-ish, will probably have at least some degree of diverticular disease. Usually something that we will find either because we do a lot of colonoscopies or people get lots of CT scans, usually very asymptomatic. They can be anywhere throughout the colon. Most of the time we see them on the left side. Sometimes we'll see them on the right as well. So things that we just kind of find because, again, we're looking in these areas a lot. If diverticula are going to cause trouble, they'll do one of two things as a general rule. One is they will become inflamed or infected. So somebody will present with diverticulitis. The other is they'll present with GI bleeding. So diverticulitis means that there's been inflammation of one of these diverticula. This is something that we'll see in maybe up to 15% of people who have known or even unknown diverticular disease. It's not super subtle. Usually these people present in the emergency room with abdominal pain typically on the left side because that's just where we see most of the burden of diverticular disease. They have fevers. They have an elevated white blood cell count. And then they'll get a CT scan that will show that there's definitely some inflammation around some area of diverticula. So that's what we see here. This is the area. So this person has sigmoid diverticulosis and you can kind of see all of this inflammation surrounding the diverticula in the sigmoid colon. Treatment. If there's no complication, these patients do very well with antibiotics. Depending on how sick they are, you may actually be able to start oral antibiotics and they can go home. Sometimes people will need a couple of days of IV antibiotics before they can transition to oral antibiotics. Now if the diverticulitis is complicated, sometimes individuals can develop an abscess or a fistula. A fistula is basically an abnormal connection between two organs that aren't supposed to be connecting. They can actually have a perforation or if the inflammation is severe enough, they can actually fully have an obstruction. So if any of these things happen, then usually there is a role for either interventional radiology for abscess drainage or surgery for resection of that area, depending on how sick somebody is. So diverticular bleeding, which is the other issue that sometimes will happen with diverticulosis, is basically there are all of these arteries that supply the colon and sometimes you can get a blood vessel that kind of erodes into this little pocket here. And so usually when this presents, it's very dramatic. Usually there is a lot of bleeding. It's painless, which contrasts it from some other causes of lower GI bleeding. So painless rectal bleeding usually makes us think that this could be something diverticular. And then usually the bleeding will stop on its own. So oftentimes a very self-limited course. So treatment, again, there is a role for colonoscopy, especially if we're able to get to somebody quickly enough. We're always looking for this, the elusive actively bleeding tick that we rarely see, but we still look. And if we do a colonoscopy and we don't find the actively bleeding diverticulum, or if we do find it and for some reason we're unable to provide endoscopic hemostasis, then we will usually move on to angiography with our interventional radiology colleagues where they can do a CT angiography or a CT angiogram, sorry, or an angiography and actually see if they can find the lesion that is bleeding or the territory where there is bleeding and they can put in coils. Or failing both endoscopic therapy and IR therapy, or if IR is not available, surgery is also an option. So hemorrhoids, just by way of definition, are these engorged blood vessels that we can develop in the anal canal. And so this is the anal canal. This is the dentate line, which is basically the rectum's answer or the anus's answer to the SCJ up in the esophagus and stomach. So if you have hemorrhoids on this side of the dentate line, we call those internal hemorrhoids. And if they're on the other side, those are external. Many causes to hemorrhoidal disease. As with many things, the older we get, the more our risk increases. Individuals who have known pelvic tumors, individuals who are pregnant, those who sit for a long time. I see this a lot in some individuals who do long-range truck driving. And a long history of constipation, particularly with a fair amount of straining, puts somebody at risk for symptomatic hemorrhoidal disease as well. Sometimes we're able to see these pretty easily with rectal exam. This device here is called an anal scope, which is probably the best way to see hemorrhoids. That can be done at just an in-office exam where you insert this into the anus. And then you're able to see. It just gives you a very good look at the very distal anal rectum, so you're able to see hemorrhoidal disease pretty easily. Colonoscopy is also an option, although truthfully, the role of colonoscopy in evaluation for rectal bleeding that we think is hemorrhoidal is to rule out other lesions, like IBD or a mass or something like this. Rectal exam and anoscopy are probably the best ways to look at hemorrhoids. So conservative management, I think, is where most people will end up falling in terms of treating hemorrhoids. So we're going to avoid constipation. If they're very symptomatic, topical steroids and suppositories are helpful for short periods of time to kind of get some of that inflammation down. Sitz baths are basically like using warm water to kind of reduce some of the swelling around the hemorrhoids. If one fails conservative therapy, then procedures like band ligation or sclerotherapy are options. And then if someone has hemorrhoids that are very large, for example, or just not great – if someone's otherwise not a great candidate for these options, then a hemorrhoidectomy with a colorectal surgeon is probably the next step. And that's all I've got for you, if you have any questions.

Colorectal Cancer Awareness Month

Colon Cancer Screening

Polyps in Colon

Colonoscopy Screening

Gastrointestinal Bleeding