This presentation on colorectal cancer – the third most common cancer in the U.S. – unpacks the risk factors (including how to assess family history); reviews symptoms, treatments and survival data; and offers guidance on meeting patients’ post-treatment needs. Increasingly, doctors must manage long-term side effects, which range widely from sexual dysfunction and elimination issues to neuropathy, chronic fatigue, depression and “chemo brain.”
So my talk today is really, uh, covering the topic of colorectal cancer for the primary care. And what I really want to do is focus on what is it that the primary care physician is most likely to see when it comes to colorectal cancer. So you'll notice in the majority this talk. It's focused really on sort of the before and after the diagnosis phase. Or I think the role for the primary care physician is actually quite important. This is I'm one of five physicians at the CSF Cancer seen in San Mateo. Um uh, and these are the physicians that are listed there. So, um, if you have certainly any questions or patients you like us to see, we are all available here. Um, and we'll have the contact information. I'll have it at the end of the slide set. So to begin with as far as just a general introduction and we're talking about colorectal cancer, the incidents and this was sort of a rough estimation that by the end of 2020 an estimated 100,000, uh, new cases of colon colon cancer and 43,000 new cases right of cancer would have been diagnosed the United States. The majority of those patients will be diagnosed with the age of set 50 but about 12% will actually be found in individuals below the age of 50. Which I think, especially in the last year or so there's been growing. Um uh, discussions about younger patients who are diagnosed and certainly has become more of a consciousness in society with some of recent individuals that have passed away at a relatively young age. Unfortunately from this disease, over 53,000 patients will die from colorectal cancer, including again about near 4000 patients below the age of 50. Um, as of January 1st of 2019, over 700,000 women, uh, both men and women individually were alive with alive in the United States with the history of colorectal cancer, some with active disease and others cancer free, Um, and a third of them having been diagnosed in the preceding five years. And that's great because we're still seeing a quite a number of patients who will survive this disease, and then we'll go on to have other long term sequelae, which is where it becomes important. Um, for primary care physicians to be aware of in their long term relationships with them. Of the course of a lifetime, we approximate that are one in 23 men and one in 25 women will be diagnosed with colorectal cancer in their lifetime. So knowing that we start thinking about what are risk factors and we know they're everywhere and we'll see if we can kind of go through all of them. Some of the general risk factors in terms of category the first one we look at his gender. Colorectal cancer incidence rates are generally higher in men than women, uh, with even greater disparity and rectal cancer. However, women, when they are diagnosed are more likely than them, especially when they're over the age of 50 developed proximal adenomas, which is important when we think about screening and what screening modality we use and patients lasting age of 45. So these are younger patients. The incidents between gender is comparable age in general. We find that for every five year age group instance, rate approximately doubles until the age of 15, when it increases by about 30%. But the median age of onset has shifted from 72 year old in the early 2000 and 66 part of which I think is really based on us now. Screening more, um, and having that be available. So we are diagnosing potentially at a higher age. Race and ethnicity is found to be a potential risk factor because the incidence and mortality is highest in African Americans, followed by American Indians and Native Alaskans. Um, slowest Asians, Pacific Islanders. It's really felt to be related to a complex issues. Not only just really ethnicity or race, but other risk factor prevalence is that we're all I think, slowly becoming aware of which, you know always has to do with health disparities, healthcare access and socioeconomic status. There are other risk factors with respect. Comorbidities. We know that certain diseases are more likely to increase the risk of colorectal cancer, including obesity, vitamin D deficiency, diabetes, inflammatory bowel disease. There are certain lifestyles that we know also increase the patient's risk factors, including cigarette smoking, a diet high animal fat, especially processed meats. Uh, you're processed meats. We know that for every 50 g of process means per day, it increases it by 18% and for red meat. If you go up for every 100 g per day, it's going up by 12%. Um, also dies are low in fruits and vegetables or don't have access to screening colonoscopies, uh, evaluation and heavy alcohol use, which is sort of defined by an average of greater than three drinks a day. Also are risk factors for developing this disease. Family history is also a risk factor depends on how close that relationship is and how many. When you have two or more first degree family positivity, the relative risk is for which is, uh, does drop. If you have are talking more about just one, um, or if their below the risk, if the if the family member who get diagnosed is below the age of 50. So I've listed here some of the relative risk factors based on those issues when we specifically talk about the age factor and you look at sort of the incidents and the data that's available. Colorectal rates have been increasing since the mid 19 eighties, especially in the adult group between 20 and 39 year old and since the mid 19 nineties, and the 40 to 54 year old, with the youngest groups having the steepest incline. Um, and part of it is also likely to some of the other risk factors we've talked about in terms of other comorbidities dietary lifestyle issues and a recent 2020 2012 to 2016 data. That incidence rates increased by 2.2% annually for individuals less than at the age of 50 years old, and by 1% annually in patients. 50 to 64 year old year olds in the 65 or older group are. Are you seeing a decline? And instead of that initial increase, we're actually seeing a slight decline Part of this. I think we are much more on top of making sure these patients do get screened. Generally, death rates has decreasing older patients but has increased in patients less than 50 year olds by about 1.3% a year since 2000 and four, um, colorectal cancer patients, less than age of 50 have a five year relative survival rates higher than their older counterparts for every stage of diagnosis. But the overall survival among patients less than age of 50 yards as the same medications than 50 64 year old because they oftentimes are diagnosed with later stage. We don't know whether or not it's more aggressive disease, or we don't always necessarily think about them having that diagnosis because they seem to be quote young. They could potentially all the factors risk factors that decreased risk. Um, we know that physical activity does correlate with a relatively decreased risk of it. The American Cancer Society does suggest about 100 and 5300 minutes of moderate to intense activity, or 75 250 minutes of vigorous intensity activity each week. The N C. C N recommends about 2.5 to 5 hours of moderate intensity activity, or 80 minutes of rigorous intensive exercise for me. Personally, I sort of rounded off to with patients who come to see me, especially the diagnosis. I tell them. Go take a good solid walk for 30 minutes five times a week, five times a week. Yeah, and, um, just to get them started and get that activity going, Dairy, uh, about 700,000 millions per day suggested that might be a relative risk reduction as your 0.9 more we more seeing a decrease in adenomas would have been appearing to be confined to the distal and coral rectal cancer area. The data is inconclusive as far as other dietary things, like whole grain fiber foley or hormonal levels, the use of incense and aspirin we have seen with long term use, um, that especially in patients less age of 70 and without excess body weight that they do appear to have less aggressive disease if they develop colorectal cancer with a better survival than non aspirin users. But it's not something that we generally recommend to everyone, um, as a preventative measure, although we obviously do. Consider in patients who are less the age of 50 who already have other reasons to be on aspirin, especially if they have increases for cardiovascular disease. And then I also wrote down that respected that might decrease risk is antibiotics and probiotics. And this has to do with the gut bio and what's there and actually an area of active research. So I don't I think there's been data that kind of supports one versus the other. It's not something that we actually recommend that patients beyond probiotics because we don't know for sure. What is the optimal? Uh, uh huh. Probiotic to use and what it is that really affects in the gut bio that might increase or decrease someone's relatively risk. Um, I do think that one is definitely diet driven. There was a recent presentation I saw which I thought was interesting, which was that they took. It was a study out of Hawaii. They took patients and follow them generationally, like two families. Um, and they looked at the risk of, uh, those patients in the risk of colorectal cancer. As a first generation immigrants. Having moved, I believe this was focused on an Asian population. So most, most of them had come from an Asian country and emigrated to Hawaii. And then they look at their risk. And then, within a year of adopting sort of the American diet, the risk for the cancer had increased similar to what was of the people that were from that native to that area. So it there is some idea that the diet and the bio may actually very much play, uh, risk factors in terms of developing, uh, colorectal cancer signs and symptoms. Um, uh, iron deficiency anemia, especially males, are usually, uh, indication to do a definitely more evaluation. AB Donald planets Crappy changes in stool caliber frequency, rectal bleeding, darker stools, lost appetite, weight loss there any actually other additional risk, simple signs and symptoms, But I sort of just chose sort of a ones that are a bit more frequent. I do also like to look at a family history because there are some patients that might flag and make us think whether or not they marry, more likely at higher risk for it. Most colorectal cancer are sporadic. Um, but you know, I do consider looking at younger patients, especially less than age 50 or have strong family histories. They may want to consider whether or not they need genetic counseling or referral. 25% of colorectal cancer patients will have a positive family history or a positive personal history, suggesting a hereditary component. Some of the family syndromes that we see include Lynch F A P or an attenuate, F A P, as well as the M u T Y H associate Paul opposes. The lynch syndrome is probably the one that most of us might see a little bit more frequently It accounts for 2 to 4% of colorectal cancer, and it's also associated with increased risk of endometrial and ovarian gastric, small bowel, urinary track, you know, and brain tumors. We do like to diagnose and identify these syndromes because it helps us with other screening modalities, in addition to defining, perhaps when or if they get their colonoscopies and screening. What about screening and diagnosis Briefly. This is sort of just a quick blur book. Some of the more common ones that we use right now, the colonoscopy to city pornography, the Flex sig and the occult tests. Um, there are certainly other modalities that are being researched out there, but these are sort of the more common ones. Um, and, uh and then I'm going to segue kind of quickly into treatment. The three main modalities that we've used our surgery, radiation and systemic therapy, uh, speaking as a medical oncologist, obviously more involved more in systemic therapy, of which there are sort of three broad general categories with chemotherapy, immunotherapy and targeted therapy. And how we use this depends a little bit on the stage. Although that's probably a discussion, a different discussion, a different talk Now I'm going to sort of now focus on sort of the survival and where we go from here if we look at the survival data, the relative overall survival Colorectal cancer is 64% of five years and 58% of 10 years, and it does vary by stage. So for the earlier stage, colorectal cancer, um, were there the survival rates, like 90% of five years, which, unfortunately, does drop off. The more aggressive and more advanced tumour is by the time you get distant. Metastatic disease to drive away at five years is at 14%. However, optimism obviously looks. The status says there's quite a number of people who do survive and go on and live their lives. Pastor diagnosis and the treatments that modalities that I just, uh listed. So the focus then becomes Where do you go after you've actually had the diagnosis and treatment? How do you then move on from it? And what are the long term surveillance and, uh, medallions we have to think about and this equality they have to live with? So when we think about following up after a diagnosis and treatment, there are certain kind of general categories that, um, uh, I tend to look at, which are the main concern for a lot of patients who live with with some of the issues after their diagnosis. Um, and that includes the risk and fear about cancer recurrence, um, which can include not only the recurrence of the original tumor, but also the development of another colorectal cancer or other malignancies, which is slightly increased, um, having had one colorectal cancer. There's also the long term reactions from the treatments, which can be multi organ and nature. Um, and there's also the quality of life issues. Um, and the average age for most survivors greater than, uh for most farmers are greater than 60 year old, 60 years old, and the quality of life does depend on the stage of diagnosed and subsequent therapy. Um, if we start to break down some of the toxicities that we see in terms of organ systems, um, and think about like long term GI toxicity is we can see bowel changes. We can manifest by general changes anywhere from general changes in bowel pattern. Um, uh, and so it can string from potentially constipation, even chronic diarrhea I'm in the various about the type of treatment or surgery that the patient has had. Chronic diarrhea can affect up to 50% of patients, um, with patients who receive a low anterior resection, which we tend to do more in patient with the rectal cancer. They definitely do see an increased risk for stool frequency and equal urgency and leakage, incontinence, gas and incomplete evacuation. So the treatment really becomes what the main issue is. So for a lot of, um, of our chronic diarrhea patients will treat with anti diarrheal medications and discuss that diets that are low in fat and and decreasing raw veggies may actually help with controlling the symptoms. For example, um, the issue for some patients, they now have a colostomy bag, which can obviously cause also long term changes. With their bowel function, they lack the bowel control and leakage issues can occur, especially at the Austin. The site, Um, and again, it's a lot of making sure that they get the medication they need to control the output, as well as any topical site therapy for irritation around the Austin site and some of the other long term talks. As you've seen is the risk increased risk for small bowel obstructions and adhesions, especially having had prior radiation, chemotherapy and surgery. And then the treatment really becomes hydration, supportive care with pain medication, diet changes and, as the last results, surgery. Um, not our first go to choice, because having more surgery than obviously creates the risk for further potentially other obstructions and intentions switching to, like urinary function dysfunctions that can occur. Um, you do see this more in rectal cancer patients because they're more likely to undergo pelvic autonomic nerve dissection. Your community in concept is common with problems about 30 to 70% especially uh um, in older patients books who made which may have other already risk factors for getting urinary dysfunctions the treatment for depending on their issues. We do talk about avoidance of foods that can irritate the bladder. More, such as Citrus tomatoes, are caffeine. There's also bladder retraining programs. Um, having the patient urinate on a fixed cycle. Kegel exercises strengthen the pelvic floor muscles we have used and the anti coal, energy and anti Masonic agents for patients stress or urge mixed incontinence and, if need be also neurology referral. There's also in that same area. The issue of long term sexual dysfunction and the extent of dysfunction depends on the extent of dissection of those ST pelvic nerves that we talked about earlier during surgery. 30 40% of previously sexually active patients do report sexual dysfunction after treatment. It is more common. Erectile versus colon cancer, 25 verse 11%. But in general, um, even without that, um, uh, level of missions some of them also have decrease, um, urge and sexual libido. Women would colorectal cancer regardless of the site. So it didn't matter if it was a rectal or colon cancer will actually report more sexual dysfunction than their counterparts in the general population. The treatment depends on the issues and what's going on for men. Uh, Oral Foster. Decorate five inhibitors to stock replacement or pharmacologic inter cabinet. Pharmacologic therapies are options for women, sexual lubricants for vaginal dryness and disappear in Europe. We are things that we will prescribe. These tend to definitely be more an issue for women, especially They had pelvic radiation therapy and treatment in that area, and then for both. It does come down to also potentially counseling and maybe some sexual health programs help deal with not only if the sexual dysfunction is more than anatomical and, sir, let me also be related to maybe to another changes. There are special considerations for toxicities when you think about radiation, which is more associated with patients and rectal cancer. As that's part of our treatment armamentarium, we do see increased risk of chronic creation, prostatitis and colitis, altered bowel function, your general and sexual dysfunction, bone loss or fractures, and second cancers they can present with chronic diarrhea. Rectal bleeding are just paying with defecation, especially with the ongoing prostatitis, which can actually go on for years. There's a higher risk for official as an intestinal obstruction, which requires surgical consult and then issue for fecal leakage and contents. And, you know erectile dysfunction which reduce reservoir capacity. Um, other things, especially with radiation, which I already kind of mentioned a little bit about, was that your general sexual dysfunction. It does cause infertility issues men. It can also lead to erectile dysfunction and decreased serum, testosterone level and women. It can cause atrophy. Fibrosis, adhesions as well as the radiation can induce for wearing failure. Period of treatment treatments are going to be like more hormone replacement therapy and vaginal dilator. I mentioned earlier the bone changes related to radiation. Um retrospective study in women who have had radiation for cervical, rectal and anal cancers in general, which are tumors that do utilize this modality of therapy, are more likely to suffer the pelvic fracture, and those who had not received preparation therapy to the area at 1.65 fold increase. So for a lot of those patients, I definitely look at doing regular bone density tests in this patient population and treat accordingly the other sort of general categories, and we look at the nerve function, um, as a result of treatment. This really oftentimes occurs as a result of usually more with the chemotherapy, which can cause long term neuropathy most to reverse. Um, once the treatment ends, however, we do see a cumulative sensory loss, uh, neuropathy with loss of sensation and tingling and pain and distal extremities. And this can also go and involve the appropriate exception, as well as the fine motor skills for some of our patients. Um, oxtail plan is a drug that we do use an average event setting so that's post surgery after a completion of their, uh, main therapy for their colorectal cancer and chronic oxide pot induced perform properties felt to be secondary to the dose dependent accumulation of platinum compounds in the dorsal root ganglia, which then causes a neuro atrophying apoptosis. So in one study, up to 10 to 12% of patients had a persistent neuropathy greater than two years after treatment. And the symptoms can range in terms of how it presents with the neuropathy from pain, um, or only symptoms that are episodic, which they find well, They'll say they noticed more in certain situations, like if they're exposed to cold environments or situations where they're on their feet for extended pressure. Extended periods of time treatment depends on the severity of the neuropathy. For pain, we have used agents such as the fluoxetine, gabapentin, tricyclic antidepressants, topical gels and creams, uh, neurology referral of disabling, um, and actually do have a study here that it's looking at potentially using duloxetine early and see if they even might prevent this neuropathy symptoms from occurring while on treatment. That trial is actually looking at using this drug while the patients start a German therapy, Um, and seeing if it will decrease the development of it after they finish their treatment. There are long term general medical complications as a result of our treatments. Fatigue and weakness is very common for a lot of our patients. Um, studies report that fatigue and weakness have occurred up to 90% of patients and cancer, uh, and more depending on the type of the treatment and intensity. And now, luckily most to improve by an average of four words, have the treatment stops. But, you know, some can actually last up to two or three months or longer. It's felt to be really due to a combination of factors, which includes chemotherapy, radiation, surgery, anemia, the status of the patient and how we there prior to their diagnosis and any comorbidities or mood. Um, and while I might say that last for two or three months, I've certainly had patients that can go up to like six months and still have these issues. Um, if not longer. The treatments are generally supportive for in one aspect that just, uh, say transfusing a patient if they need it for significant anemia or adjustments of their medications. If need be like their pain medications or things like that, Uh, and then we also want to treat compound issues is to sleep a pain, vitamin deficiency. But the one thing that I found especially for a lot of our patients who have actually been on chemotherapy and have fatigue, especially after treatment is they oftentimes are not as active during therapy because the chemo sort of takes about them and they are not as active as the one before. So there's a lot of de conditioning and decreased stamina, so I will refer to like PT and Exercise Program Live. Strong, for example, is a free program that is offered to patients. Usually, I believe, to the Y M. C A. It's a 12 week, uh, exercise program, of course, for patients have completed treatment for their cancer. Um, and it's regardless of the cancer subtype or the treatments that they've had but just conclusion of therapy and they go under, they sort of set up for these 12 week programs that help them, um, do focus exercise for their, um, weaknesses and deficiencies and see if they can increase their level of function. Um, UCSF also has a Cancer Exercise Counseling program, which is one and one which patients can call other, um, issues that people patients have talked about commonly. What sort of as a result of chemotherapy has been the issue of chemo, brain or the other term is that cancer treatment related cognitive dysfunction and the symptoms for chemo brain really varies from patient to patient. It can be anywhere between decreased mental sharpness. They just don't feel like they can focus as well. Or things just take longer to memory lapses to trouble concentrating a learning skill We're just taking longer to finish task of trouble finding words. It's actually quite prevalent and has been found up to 30% of patients before came out there. We have 2 75 during and then we'll drop off a little bit, Still can persist up to 35% in patients, uh, years after their completion of treatment. Um, the underlying mechanism is not well understood, but it felt to be a combination of the patient themselves, perhaps some component of immune dysfunction, mural toxicity or possibly genetics. It can actually occur While it's concerned, chemo brain can actually occur not only to chemotherapy, but also radiation surgery. There are risk factors that we find might increase the prevalence and severity of the chemo brain, which includes other drugs that are used in part of the therapy, like pain medications or steroids and general anesthesia. Other health issues like diabetes and hypertension. Um, if they have emotional distress or anxiety, if they're older, they're undergoing hormonal changes. Or they have any nutritional deficiencies and generally other substance, like alcohol that can affect cognition and frailty. The treatment involves cognitive rehab. In some cases, I'll actually just have them do exercises, Um, that it can improve their ability to think and focus. Meditation definitely helps, especially for patients of anxiety issues or depression. We do like to address any sort of sleeping issues, and I do talk to them for some people, especially if it's to also aggravated by other comorbidities. Let's say if someone had a history of already some mild dementia activity modifications that we have them do demanding activities when the energy and focus maybe highest I'm having the news reminders are planning and setting up routines. I sort of also do talking about diets that can sometimes help, like diets that help hired, and vegetables and Western agents like alcohol that can affect cognition. And then we evaluate also for any other disorders that can lead to cognitive function. Weight changes are also fairly common in patients. Um, cancer patients, Um, and they can have long. It could be a long term issue, um, patient and long term, which is weight loss or gain. It can either be in one direction, other after diagnosis and therapy. The metabolism, absorption of nutrients and food can be an issue for patients with colorectal council. Long after the treatment is complete, systemic therapy can lead to weight increases, which can be difficult to remove after completion of therapy. We give them steroids oftentimes with therapy as part of, um, to help them with sometimes the nausea and those things. But that can also lead to changes, metabolism and weight gain. Um, patients also have to increase mobility on treatment due to fatigue, or sometimes they won't get a triggering nausea on chemotherapy, which causes them to eat more. Uh, some people have intense food. Cravings are altered taste, which then means in an altered diet. Um, chemotherapy can decrease metabolism and cause menopause, and some women. And because of that, those weight changes do have implications in health for patients who have chronic weight loss, especially if they have issues with absorption. Uh, and they have a cost me to have a lot of diarrhea. A registry did show that long term weight loss and five years associate with decrease colorectal specific survival and overall survival on the opposite of over for overweight patients. Generally, they're also at higher risk for colorectal cancer and have implications for patients. General health, especially when we're thinking about other diagnoses that as primary care physicians, you might see, including hypertension, diabetes and arthritis. The treatment for that we talk about really has to do with oftentimes nutrition counseling and making dire team dietary and exercise adjustments accordingly. And then the other issues that we also deal with that's fairly common are long term psychosocial issues. I think cancer patients do have more psychosocial issues in the general population. Uh, we do need to screen for depression anxiety up to 24% survivors. And once they have depression scores high enough to warn the diagnosis clinical progression. Um uh, they're in colorectal cancer patients. There are some specific psychosocial issues. Not only the fear of cancer current about the new cancer as well as adverse reaction to treatment, but there's also the negative body image, especially if they've had a stoma. Um, there's also problems in general, with cancer patients, about social relationships and returning to work and the financial strain that the treatment has caused. We do see reduced social, emotional, sexual occupational function after diagnosis and treatments. And, um, a lot of this is identifying it. And then perhaps if they need to get in treatment with anti depressants and anti analytics, um, and then referring to support groups for psychologists and psychiatric referral. And then it's getting that patient back to their normal, uh, state of health. After the cancer diagnosis, Um, cancer patients will often put the other co morbid co morbid diseases on hold right. It becomes they don't want to really necessarily checking their cholesterol and hypertension or anything like that. And so they have less consistent contact with their PCP during this time. So sort of integrating their PC key back is important, especially once they're done with that chemotherapy, because I think the primary care is crucial in the care of the patient after the immediate therapy for optimizing treatment for the other comorbidities after therapy, Um, for example, 75 to 35% of patients with colorectal cancer received adjuvant therapy. RBS, which, as we talked about the beginning as a risk factor for getting full rectal cancer so addressing that going forward is an issue and then also it's encouraging preventative measures and promoting overall health, respect to exercise smoking cessation and then continue cancer screening. That's it. And I'm happy to take questions. This is the contact information that I have, uh, by all means. Obviously feel free to contact me. You can always certainly email me directly if you probably the quickest way. If you want me to just type in a quick response.