Image Credit: CDC on Unsplash
The Colon Cancer Foundation (CCF) spoke with Alessandro Mannucci, MD, who received the 2022 Colon Cancer Foundation and CGA Colorectal Cancer Research Scholar Award to present his work at the 2022 CGA-IGC Annual Meeting in Nashville, TN, November 11-13. Dr. Mannucci, a medical resident in gastroenterology and gastrointestinal endoscopy at the San Raffael Hospital, Milan, Italy, will be presenting his work titled ‘Lynch Syndrome is Associated with Fecal and Salivary Dysbiosis’.
CCF: What is the importance of the gut and the microbial flora in the human body, and how do they influence our well-being?
Dr. Mannucci: Broadly speaking, the microbiota is made up of many different cell types, including bacteria, viruses, fungi, and other kinds of microorganisms. However, our study specifically focused on bacteria because it is known that we have way more bacteria in our body than human cells. That alone indicates the significant impact of the microbiome on different phases of our life—from childhood to adulthood.
The disruption of a healthy microbiome equilibrium causes the components of the microbiome to converge toward a proinflammatory environment in several ways. Certain species increase the risk of colorectal cancer [CRC]. Organisms that increase in numbers in the presence of CRC are generally proinflammatory. This understanding has come simultaneously with the realization that inflammation is one of the new pillars of cancer. The inflammatory environment is a disruption that is particularly important when studying the colon because the colon is the first organ in direct contact with the microbiome.
CCF: Can you tell us the importance of this fact in your research?
Dr. Mannucci: In our study, we had a suspect: the microbiome. While the microbiome is known to play a role in turning a normal cell cancerous, this association had not been investigated in the context of the hereditary Lynch syndrome [LS]. Mutations in one of five genes can lead to LS.
There is a spectrum of manifestations of LS, the most important of which is CRC, although developing the cancer is determined by penetrance. We were interested in knowing if the microbiome has a role in this process.We wanted to know if the microbiome in individuals with LS who had not yet developed cancer, differed from those without LS. While it may be difficult to explain a cause-and-effect relationship, it is important to understand why a difference exists. Germline pathogenic variants may influence the formation, conformation, and diversity of the microbiome, or vice versa. Interestingly, we found that the fecal microbiota was significantly different among those with LS, but we need more data.
CCF: What is the relevance of microorganisms in the oral cavity?
Dr. Mannucci: In individuals with LS, the cells within their mouth are also mutated. So we decided to test the differ
Alessandro Mannucci, MD
ence between the fecal and oral microbiota among those with and without LS and found that not only is the fecal microbiota different, which you would expect because LS is associated with an increased risk of CRC, but we also observed a proinflammatory change in the oral microbiota. We now know that the oral microbiota of patients with LS differs from that of healthy individuals, which raises the question that pathogenic variants inside the mouth may interact with microbiota species that cause a proinflammatory shift.
Another hypothesis is that individuals with this particular hereditary predisposition to CRC may also have a predisposition to orthodontic diseases. While we currently have limited understanding of this association and are testing the hypothesis, our discovery of the unexpected difference of a proinflammatory environment led us to suppose that maybe something else was at play.
What is interesting when we talk about scientific studies is not only what you are interested in, but also what you compare it to. In our case, we compared LS patients without cancer diagnosis to unrelated, healthy patients. So we did not have within-family control, which other investigators might want to look at–within the family or individuals with LS in different age groups.
CCF: How long will the subjects in your study be followed?
Dr. Mannucci: While we usually follow patients throughout their lives, five to ten years of follow-up will give us more insight. The idea is that if there is a proinflammatory environment within that patient, it could trigger cancer at an earlier age. To test that hypothesis, we are collecting samples of relatively young individuals, and we want to follow them and see if they develop cancer. The mean age of patients with LS was 48 years plus or minus 16 years.
CCF: Does diet influence microbial flora and the balance of pro- versus anti-inflammatory microbial flora in the oral cavity and the gut?
Dr. Mannucci: You raise a very, very interesting point! The microbiota is adaptable, and it can change very rapidly. There is some robustness to it, meaning you shape the health of your microbiome during your youth and by the time you reach adolescence or young adulthood, your microbiota is pretty much set. However, it can change based on your diet.
One of our study limitations is that we could not control for diet. We could control other factors that can influence the changes within the microbiota itself, such as age, sex, smoking, the presence of cancer, or chemotherapy treatment—factors that can modify the shape, overall biodiversity, and the general composition of the microbiota.
However, we could not control the overall dietary composition. In the future, we may control our patients’ diet and place them either on a Western diet as opposed to a Mediterranean diet or a modern diet.
Assuming that individuals with a higher risk of CRC follow an anti-inflammatory diet, you would expect to see an anti-inflammatory microbiota. We found the opposite; we found a proinflammatory change within the microbiota. While we are planning to control for participant diets in future studies, an alternative approach would be to include individuals with different genetic backgrounds and eating similar diets to investigate the differences in their microbiota.
But remember, this is currently a hypothesis. What we know now is that these genetic predispositions are associated with a difference in the microbiota composition, and that difference itself is a proinflammatory environment. We don’t know the cause-effect relationship or how that can be altered, yet.
CCF: What would be a key takeaway from your study findings?
Dr. Mannucci: A key takeaway is that we’re developing a tool to better understand who does or does not get cancer. Hopefully, it will become a tool or a target to reduce the risk of cancer. I completely agree that diet can be a big influence. So maybe in the near future, we will be able to tell our patients that if they stop smoking, regularly exercise, reduce the intake of fatty foods, and if they have a specific kind of diet, they can reduce their risk of CRC. The microbiota has the potential to become an instrument for reducing the risk of cancer, but we are not there yet.
Thank you to Sahar Alam, CCF’s Colorectal Cancer Prevention Intern, for her assistance with this post.
In Conversation With Dr. Alessandro Mannucci: Understanding the Relation Between Lynch Syndrome and the Oral and Fecal Microbiota
Image Credit: CDC on Unsplash
The Colon Cancer Foundation (CCF) spoke with Alessandro Mannucci, MD, who received the 2022 Colon Cancer Foundation and CGA Colorectal Cancer Research Scholar Award to present his work at the 2022 CGA-IGC Annual Meeting in Nashville, TN, November 11-13. Dr. Mannucci, a medical resident in gastroenterology and gastrointestinal endoscopy at the San Raffael Hospital, Milan, Italy, will be presenting his work titled ‘Lynch Syndrome is Associated with Fecal and Salivary Dysbiosis’.
CCF: What is the importance of the gut and the microbial flora in the human body, and how do they influence our well-being?
Dr. Mannucci: Broadly speaking, the microbiota is made up of many different cell types, including bacteria, viruses, fungi, and other kinds of microorganisms. However, our study specifically focused on bacteria because it is known that we have way more bacteria in our body than human cells. That alone indicates the significant impact of the microbiome on different phases of our life—from childhood to adulthood.
The disruption of a healthy microbiome equilibrium causes the components of the microbiome to converge toward a proinflammatory environment in several ways. Certain species increase the risk of colorectal cancer [CRC]. Organisms that increase in numbers in the presence of CRC are generally proinflammatory. This understanding has come simultaneously with the realization that inflammation is one of the new pillars of cancer. The inflammatory environment is a disruption that is particularly important when studying the colon because the colon is the first organ in direct contact with the microbiome.
CCF: Can you tell us the importance of this fact in your research?
Dr. Mannucci: In our study, we had a suspect: the microbiome. While the microbiome is known to play a role in turning a normal cell cancerous, this association had not been investigated in the context of the hereditary Lynch syndrome [LS]. Mutations in one of five genes can lead to LS.
There is a spectrum of manifestations of LS, the most important of which is CRC, although developing the cancer is determined by penetrance. We were interested in knowing if the microbiome has a role in this process.We wanted to know if the microbiome in individuals with LS who had not yet developed cancer, differed from those without LS. While it may be difficult to explain a cause-and-effect relationship, it is important to understand why a difference exists. Germline pathogenic variants may influence the formation, conformation, and diversity of the microbiome, or vice versa. Interestingly, we found that the fecal microbiota was significantly different among those with LS, but we need more data.
CCF: What is the relevance of microorganisms in the oral cavity?
Dr. Mannucci: In individuals with LS, the cells within their mouth are also mutated. So we decided to test the differ
Alessandro Mannucci, MD
ence between the fecal and oral microbiota among those with and without LS and found that not only is the fecal microbiota different, which you would expect because LS is associated with an increased risk of CRC, but we also observed a proinflammatory change in the oral microbiota. We now know that the oral microbiota of patients with LS differs from that of healthy individuals, which raises the question that pathogenic variants inside the mouth may interact with microbiota species that cause a proinflammatory shift.
Another hypothesis is that individuals with this particular hereditary predisposition to CRC may also have a predisposition to orthodontic diseases. While we currently have limited understanding of this association and are testing the hypothesis, our discovery of the unexpected difference of a proinflammatory environment led us to suppose that maybe something else was at play.
What is interesting when we talk about scientific studies is not only what you are interested in, but also what you compare it to. In our case, we compared LS patients without cancer diagnosis to unrelated, healthy patients. So we did not have within-family control, which other investigators might want to look at–within the family or individuals with LS in different age groups.
CCF: How long will the subjects in your study be followed?
Dr. Mannucci: While we usually follow patients throughout their lives, five to ten years of follow-up will give us more insight. The idea is that if there is a proinflammatory environment within that patient, it could trigger cancer at an earlier age. To test that hypothesis, we are collecting samples of relatively young individuals, and we want to follow them and see if they develop cancer. The mean age of patients with LS was 48 years plus or minus 16 years.
CCF: Does diet influence microbial flora and the balance of pro- versus anti-inflammatory microbial flora in the oral cavity and the gut?
Dr. Mannucci: You raise a very, very interesting point! The microbiota is adaptable, and it can change very rapidly. There is some robustness to it, meaning you shape the health of your microbiome during your youth and by the time you reach adolescence or young adulthood, your microbiota is pretty much set. However, it can change based on your diet.
One of our study limitations is that we could not control for diet. We could control other factors that can influence the changes within the microbiota itself, such as age, sex, smoking, the presence of cancer, or chemotherapy treatment—factors that can modify the shape, overall biodiversity, and the general composition of the microbiota.
However, we could not control the overall dietary composition. In the future, we may control our patients’ diet and place them either on a Western diet as opposed to a Mediterranean diet or a modern diet.
Assuming that individuals with a higher risk of CRC follow an anti-inflammatory diet, you would expect to see an anti-inflammatory microbiota. We found the opposite; we found a proinflammatory change within the microbiota. While we are planning to control for participant diets in future studies, an alternative approach would be to include individuals with different genetic backgrounds and eating similar diets to investigate the differences in their microbiota.
But remember, this is currently a hypothesis. What we know now is that these genetic predispositions are associated with a difference in the microbiota composition, and that difference itself is a proinflammatory environment. We don’t know the cause-effect relationship or how that can be altered, yet.
CCF: What would be a key takeaway from your study findings?
Dr. Mannucci: A key takeaway is that we’re developing a tool to better understand who does or does not get cancer. Hopefully, it will become a tool or a target to reduce the risk of cancer. I completely agree that diet can be a big influence. So maybe in the near future, we will be able to tell our patients that if they stop smoking, regularly exercise, reduce the intake of fatty foods, and if they have a specific kind of diet, they can reduce their risk of CRC. The microbiota has the potential to become an instrument for reducing the risk of cancer, but we are not there yet.
Thank you to Sahar Alam, CCF’s Colorectal Cancer Prevention Intern, for her assistance with this post.
Fecal Immunochemical Tests Affordable and Effective for Colorectal Cancer Screening
As we emerge from the initial waves of COVID-19, patients may have been reluctant to take more time out of their life for a colonoscopy prep, procedure, and recovery. Fortunately, non-invasive stool-based screening tools, such as fecal immunochemical tests (FIT) and multi-target stool DNA (mt-sDNA or Cologuard), are practical options that allow patients to provide a sample in the comfort of their home and could address access and care gap issues as they are less expensive.
According to a new study presented during the Scientific Forum at the American College of Surgeons Clinical Congress 2022, these non-invasive stool-based screening methods are equally effective for screening for early-stage colorectal cancer (CRC). Pavan K. Rao, MD, a general surgery resident at Allegheny Health Network in Pittsburgh, Pennsylvania, presented study results that evaluated 117,519 enrollees within the Highmark claims database who underwent CRC screening in 2019. The researchers found:
Similarly, these results support previous studies out of Japan and the Netherlands that found FIT was more cost-effective than other types of non-invasive CRC screening tests. This provides our healthcare system with an efficient alternative at a reduced cost that maintains patient outcomes without compromising the quality of care.
Patient Preference Key to Success of Colorectal Cancer Screening Programs
Colorectal cancer (CRC) screening is a vital preventative method to detect and remove a polyp and to diagnose cancer before it advances to an incurable stage. CRC screening options include endoscopy and stool-based testing. Now a new study that surveyed unscreened individuals at average risk for CRC has found that people have a preference for the stool-based screening option.
The third most diagnosed cancer in the U.S., over 5 million people worldwide currently live with CRC. One method of CRC screening is a colonoscopy, which detects swollen, abnormal tissues, polyps, or cancer in the large intestine (colon) and rectum. Another form of CRC screening is the fecal immunochemical test (FIT). FIT is one of the most widely used CRC screening methods globally and is an affordable screening tool for studying large populations. FIT detects hidden blood in stool, a potential early sign of cancer, and it has an overall 95% diagnostic accuracy for CRC.
It is estimated that 106,180 new colon cancer cases and 44,850 new rectal cancer cases will be diagnosed in the U.S. in 2022. With the screening age for CRC for average-risk adults lowered to 45 years, we need a better understanding of what the various age groups may prefer as a screening option to improve compliance and screening rates.
The new study that was published has found that individuals in the 40-49 age group and those ≥50 years prioritized test modality above effectiveness when choosing their screening test. The findings of this study demonstrate that:
These results conflict with current CRC screening approaches in the U.S., where colonoscopy is the screening test customarily used. Furthermore, these findings prompt the modification of current CRC screening guidelines and suggest that healthcare providers consider sequential-based screening procedures where FIT is offered before colonoscopy. The results, however, are consistent with a 2007 study, which supports the effectiveness of providing FIT before colonoscopy—the percentage of patients that were up-to-date with screening increased by almost 50% between 2000 and 2015 when they were offered direct-to-patient annual FIT outreach with colonoscopy.
Scheduling delays and longer waiting times for colonoscopies have increased as millions of newly eligible individuals need a colonoscopy, all of which can strain resources and delay access and early screening for patients, especially for those at greater risk for CRC. Sequential approaches for CRC screening, such as those that offer FIT before colonoscopy, can help acknowledge and adjust to the increased need for screening and the lack of resources and help prioritize access to colonoscopy for those at greater risk for CRC.
Sahar Alam is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Setting it Straight: The Colonoscopy Controversy
A new study published in the New England Journal of Medicine has sparked controversy—this 10-year study involving nearly 85,000 participants in Europe highlighted that colonoscopies cut the risk of colorectal cancer (CRC) only by about a fifth, far below estimates from earlier scientific studies, and didn’t substantially reduce deaths, raising the possibility that the invasive procedure is not worth it. Doctors in the U.S. are now concerned that the study’s results could cause doubt about the effectiveness of a colonoscopy, which is a recommended CRC screening approach for those 45 and older, to be conducted once in ten years. Despite the confusion about the effectiveness of colonoscopies, national news articles and gastroenterologists in the U.S. have rebuked these conclusions.
A major limitation that experts found with the study was that only 42% of the people who were invited to get a colonoscopy actually had one. However, researchers still reported the outcomes for the entire cohort, regardless of whether or not they underwent a colonoscopy. The study found that of those who were invited to have a colonoscopy—whether they got it or not—there was an 18% reduction in developing the disease and no statistically significant reduction in the likelihood of CRC death. Many don’t believe that this is representative of what happens in the U.S., where colonoscopy is more widely accepted as a standard screening protocol compared to European countries, and was a serious shortcoming of the study. In fact, when the individuals who did not get a colonoscopy were removed from the study, the risk of developing CRC among those who did get a colonoscopy reduced by an estimated 31% and the risk of death reduced by about 50%.
As Robin Mendelsohn, MD, co-director of the Center for Young Onset Colorectal and Gastrointestinal Cancers at the Memorial Sloan Kettering Cancer Center, argues “in order for a colonoscopy to be effective, you have to have it done”.
Andrew Albert, MD, a member of the Colon Cancer Foundation (CCF)’s Interdisciplinary Medical Advisory Council (IMAC), said, “While the NordICC trial demonstrates the need for challenging the status quo related to colonoscopy, this remains an effective screening tool, particularly for individuals at average risk who may be on the fence about going in for screening. Misinformation is dangerous, especially in healthcare. If we miss catching colorectal cancer at an early stage—which is what a colonoscopy is very good at—it can have a big impact on survival. We need to remember that CRC is preventable, and treatable when caught early.”
IMAC member Matthew A. Weissman, MD, MBA, FAAP, told CCF, “I hope that the findings of this study, which have been taken out of context by many, will not discourage folks from getting screened for colon cancer by colonoscopy or other appropriate methods, which is extremely important in early detection (and prevention) of this deadly disease.”
In an accompanying editorial in the same issue, experts point to the need for a longer follow-up time for the impact of screening colonoscopy to be realized. They also point out that the skill of the endoscopist conducting the procedure has a significant impact on the detection rate—29% of endoscopists in the trial had an adenoma detection rate below the recommended 25%.
Consequent to this study, the American Society for Gastrointestinal Endoscopy (ASGE) issued a public statement that colonoscopy remains the best and most proven way to detect and prevent CRC incidence and death. The American Cancer Society also weighed in on the study, pointing to the high number of participants who didn’t undergo the procedure. Adam Lessne, MD, a gastroenterologist at Gastro Health in Florida told VeryWell Health that “when you take away the limitations, it’s proven again that colonoscopies do save lives and they do reduce the risk of death.”
The bottom line is that a screening test of any kind—stool-based or colonoscopy—is better than none, and CRC is preventable with regular screening. For detailed information on various CRC screening methods and current screening guidelines, visit this page on the Colon Cancer Foundation’s website.
Kitty Chiu is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Medicaid Expansion May Have Improved Diagnosis of Early-Stage CRC
Health insurance coverage is an important determinant of access to health care. Most people in the U.S. receive health insurance through their employers and many others qualify for government insurance programs like Medicare (generally for those >65 years) or Medicaid (for low-income families/individuals). The 2010 Affordable Care Act mandated preventive screening coverage for those who are enrolled in Medicaid and provided support to participating states. A cross-sectional cohort study has now revealed that after Medicaid expansion in 2014, the proportion of patients diagnosed and treated at Commission on Cancer–accredited facilities increased within expansion states and decreased in non-expansion states.
This study evaluated whether the proportion of patients diagnosed with early-stage colorectal cancer (CRC) changed over time within states that expanded Medicaid, compared with non-expansion states. The authors queried the multicenter registry data from the National Cancer Database (2006-2016) and identified a total of 10,289 patients in expansion states and 15,173 patients in non-expansion states. They found:
Similarly, a study published in the Journal of American Surgeons also found that Medicaid expansion has had a notable impact on the diagnoses of early-stage CRC compared to non-expansion states.
Improved insurance coverage following Medicaid expansion may have facilitated access to screenings and earlier diagnoses.
For more information on insurance coverage for CRC screening, please visit: Insurance Coverage for Colorectal Cancer Screening.
Kitty Chiu is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Distance, Region, and Insurance Coverage Associated With Increased Risk of Advanced Colon Cancer
Early-stage colon cancer is treatable and has a very promising survival rate. However, less than 40% of new colon cancer diagnoses are early-stage disease. Now, a new study has identified an association of distance, region, and insurance coverage with advanced colon cancer at initial diagnosis. Utilizing the Nation Cancer Database, patients 18 years or older diagnosed with colon cancer as a primary diagnosis between 2010 and 2017 were compared in terms of distance to their medical facility, region of residence, and insurance coverage.
The study found that patients at an increased risk of advanced pathologic disease:
Sahar Alam is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Lessons Learnt: COVID-19 Pandemic Impacted FIT Testing in the Early Days
Globally, the COVID-19 pandemic has led to sharp declines in cancer screening rates. Screening tests were halted as national lockdowns began as healthcare centers needed to prioritize COVID-19 patients. A retrospective cohort study revealed that during the early days of the pandemic in 2020, fewer fecal immunochemical test (FIT) screenings and colonoscopies resulted in fewer patients being diagnosed with colorectal cancer (CRC) and advanced adenomas than in 2019. In April 2020, colonoscopy volumes were significantly lower than in April 2019, with a 26.9% decrease in colonoscopy volume. Overall, there was an 8.7% reduction in CRC cases diagnosed by colonoscopy in 2020. This has fueled concerns of a potential negative impact on cancer prevention and care.
The study mentioned above analyzed the effect of the COVID-19 pandemic on CRC screening and diagnostic testing among 18-89 year-olds enrolled in the Kaiser Permanente Northern California health plan in 2019 and 2020. Researchers measured changes in the number of mailed, completed, and positive FITs; colonoscopies; and cases of colorectal neoplasia detected by colonoscopy. Findings show that when the pandemic-related stay-at-home orders were issued in March 2020, there was a dramatic decline in FIT mailings. Similarly, in South Australia, retrospective analysis on surveillance colonoscopy in patients at high risk for CRC revealed that there was a 51.1% decrease in surveillance colonoscopy procedures from April–June 2019 compared to April–June 2020, the period where the region faced the most difficulty due to COVID-19.
The reduction in CRC screenings during the pandemic suggests that patients may have been reluctant or unable to undergo screening. Furthermore, challenges with pre-pandemic CRC screening were amplified during the pandemic. For instance, stress levels in the general population increased and those who may have skipped screening due to work obligations were more likely to miss setting up a colonoscopy during the pandemic. Fear of contracting COVID-19 may have been another barrier. Another issue that was evident during the pandemic was healthcare inequities that disproportionately impacted medically-underserved communities.
Given the massive delays in traditional methods of screening, healthcare centers had to develop alternative approaches to ensure continued screening after the initial wave of COVID-19, such as the increased adoption of telehealth services. For CRC screening, the use of FIT was arguably the best alternative to colonoscopy procedures during the COVID-19 pandemic. This remote option gives patients a lot of flexibility with their screening, as they are able to take the test safely in the comfort of their own homes.
These findings may help inform the development of strategies for CRC screening and diagnostic testing during future national emergencies.
Kitty Chiu is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Ryan Reynolds Documents a “Potentially Life-Saving” Colonoscopy After Losing a Bet
A friendly bet resulted in a potentially life-saving procedure for actors Ryan Reynolds and Rob McElhenney. Reynolds bet McElhenney that if he learned to speak Welsh, Reynolds would let a camera crew document him as he underwent a colonoscopy. In partnership with Lead from Behind, Reynolds documented and shared his experience on YouTube.
Both Reynolds and McElhenney turned 45-years-old this year. In May 2021, the US Preventive Services Task Force (USPSTF) revised the colorectal cancer (CRC) screening age for average-risk adults to 45 years instead of 50. Reynolds noted in his video description, “I made a bet. I lost. But it still paid off.” Reynolds’ colonoscopy, conducted by Jonathan LaPook, MD, a gastroenterologist with NYU Langone’s Colon Cancer Screening and Prevention Program, resulted in the detection and removal of an “extremely subtle polyp” on the right side of his colon. McElhenney also decided to undergo a colonoscopy, which resulted in the identification of three polyps. Dr. LaPook emphasized, “This [colonoscopy] saves lives. Pure and simple.”
Importance of Colorectal Cancer Screening
Colorectal cancer (CRC) is the third most diagnosed cancer and over 5 million people worldwide currently live with CRC. According to the American Cancer Society, the lifetime risk of developing CRC is 1 in 23 for men and 1 in 25 for women, and recent research indicates an increased incidence of CRC among individuals younger than 50 years of age. There will be an estimated 106,180 new colon cancer cases and 44,850 new rectal cancer cases in the United States in 2022. While CRC screening rates have significantly improved over the past 20 years, only 65%-70% of age-eligible individuals achieve screening nationally. Screening is a significantly effective and preventive method to detect CRC before it advances to an incurable stage.
When to Schedule a Colonoscopy
The American Cancer Society and USPSTF recommend screening should begin at 45 years for average-risk adults. Individuals who are at a higher risk of developing CRC may need to be screened earlier.
What to Expect During a Colonoscopy
A colonoscopy detects swollen, abnormal tissues, polyps, or cancer in the large intestine (colon) and rectum. Before a colonoscopy, patients are required to empty their colon by following a specific diet recommended by their doctor, taking a prescribed laxative, and adjusting any daily medications as instructed by their doctor. On the day of the procedure, a long, flexible tube (colonoscope) is inserted into the patient’s rectum under anesthesia. A tiny camera at the tip of the tube allows the doctor to view the colon. If polyps and abnormal tissues are detected, they can be removed during the colonoscopy itself, just like in Reynolds’ and McElhenney’s procedures. According to the American Society for Gastrointestinal Endoscopy, more than 40% of adults over the age of 50 years have precancerous polyps in the colon.
What Are Colorectal Cancer Symptoms?
CRC may not cause symptoms immediately. Screening is the most effective method to detect and remove polyps before they advance into malignant disease. Speak to your doctor if you are 45 or older, have a family history of CRC, or notice any abnormal symptoms.
Remember: CRC survival is 90% if detected at an early stage when the cancer is localized and has not spread to other sites or organs.
Sahar Alam is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Ultra-Processed Foods a Risk Factor for Colorectal Cancer
Diet has been recognized as an important modifiable risk factor for colorectal cancer (CRC). In particular, diets consisting of high fats and carbohydrates, such as red and processed meats, are considered high-risk. Now, a large-scale cohort study among U.S. residents has revealed that high consumption of ultra-processed foods might increase CRC risk in men—the third most diagnosed cancer in the U.S..
For the past two decades, researchers have witnessed a significant increase in the consumption of ultra-processed foods, industrial ready-to-eat or ready-to-heat products high in refined sugars, refined starch, and trans fats. Ultra-processed foods currently contribute to 57% of the total daily calories consumed by American adults. A growing pool of evidence suggests that ultra-processed foods increase CRC risk by altering the composition and diversity of gut microbiota and increasing the risk of obesity. Some examples of these foods include bread and rolls, breakfast bars and cereals, hotdogs and other processed meats, packaged sweet snacks and desserts, jams and jellies, and condiments, among other things.
The above-mentioned study analyzed responses from over 200,000 participants—159,907 women from the Nurses’ Health Study (1986-2015) and 46,341 men from the Health Professionals Follow-up Study (1986-2014)—across three large prospective studies in the U.S. that assessed dietary intake. The follow-up period was between 24-28 years. At the time of study enrollment, none of the participants had any cancer diagnoses. Information on dietary intake, demographic characteristics, lifestyle factors, and medical conditions of the participants was obtained through food frequency questionnaires every four years.
Of the 206,000 participants who were followed for more than 25 years, the research team documented 1,294 cases of CRC among men and 1,922 cases among women. The study findings indicated that those who consumed the highest amount of ultra-processed foods had a 29% higher risk of CRC compared to those with the lowest consumption. However, this was not observed among women. Among women, the risk of CRC was positively associated with higher consumption of ready-to-eat or ready-to-heat mixed dishes. In contrast, higher consumption of yogurt and dairy-based desserts was linked to a reduced risk of CRC among women.
These findings support the importance of limiting certain types of ultra-processed foods for better health outcomes. Here are some additional resources on diet and lifestyle and how they can influence your colon health and overall wellness:
Kitty Chiu is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.
Image credit: Tim Toomey on Unsplash
ASCO 2022: Access, Education, and Adherence Important for Colorectal Cancer Screening
A series of abstracts presented at the 2022 Annual Meeting of the American Society of Clinical Oncology identified ways to improve access to colorectal cancer (CRC) screening, including for minority and underserved populations; compared different screening modalities for efficiency; and highlighted ways to improve the impact of screening programs at health centers. The infographic below provides a snapshot of these research findings.
Abstracts presented at the 2022 Annual Meeting of the American Society of Clinical Oncology.
Details on the studies and their findings can be found below:
Juhi Patel was a Colon Cancer Prevention Intern with the Colon Cancer Foundation.