Nutrition & Colorectal Cancer Prevention Series: Blog 2

The first installment of this blog series provided an overview of the molecular pathways that enable dietary interventions to prevent and reduce the spread of colorectal cancer (CRC) cells in the body. These pathways have laid the foundation for this week’s installment: addressing the systemic barriers that prevent individuals from accessing the nutrition they need to reduce CRC risk. 

Connecting the Dots: Access, Healthy Food, and CRC

The link between food deserts (areas with limited access to low-cost yet nutritious food) and health outcomes is well established. Like most health disparities in the U.S., black, brown, and low-income communities are more likely to live in locations with sparse options for fresh, healthy dietary choices. Individuals living in these food deserts often need to drive an extended distance to access fresh fruits and vegetables, as the options near their residences are canned, frozen, or unavailable. Additionally, food swamps are similarly deficient in healthy nutritional options but are marked by a high ratio of fast food to fresh food options. Lack of proximity to fresh and less processed foods contribute to the social determinants of health and make it far more difficult for individuals in these communities to engage in proactive prevention. 

In an article published in May of this year, researchers explored the epidemiologic links between counties with high food desert and food swamp scores and obesity-related cancer mortality rates. Individuals residing in counties with high food swamp scores were found to have significantly (77%) higher odds of obesity-related cancer mortality. The authors similarly identified a positive dose-response relationship between obesity-related cancer mortality and food desert and swamp scores. 

Improving Access to Fresh Foods in These Communities

While individuals living in these geographic locations have substantial barriers, local organizations can help provide services that bridge the gap. Many local food pantries have developed programs to bring fresh foods to communities in need. Volunteers will pack pre-selected boxes of fresh ingredients and set up a free farmer’s market in a community that lacks access to those ingredients, eliminating the transportation barrier and making dietary prevention, or the process of maintaining a balanced and nutritious diet to prevent disease, a more accessible goal. 

Feeding America has an online tool that locates mobile food pantries with a click and a zip code. Local food pantries may also provide delivery services to elderly or disabled individuals, so check in with your local organization to learn more!

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Picture credit OpenClipart-Vectors from Pixabay.

Nutrition & Colorectal Cancer Prevention Series: Blog 1

The link between nutrition and colorectal cancer (CRC)  prevention is well established. Researchers have found that low-inflammation diets, such as Mediterranean diets, are associated with lower risk of CRC. This study also affirmed the link between sugar intake and CRC risk, with individuals who consume beverages high in sugar being more likely to develop rectal adenomas. 

Other studies have explored the links between highly processed foods and development of colorectal adenomas. In addition to highly processed foods, canned foods have also been shown to increase risk of colorectal polyps when measured against fresh fruits and vegetables.

These associations provide evidence that a low-inflammation diet that is low in sugar and processed foods can lower the risk of developing CRC; however, there is limited research on the impact of nutritional interventions on those who are already diagnosed. 

Can Dietary Interventions Improve CRC Outcomes?

A study published earlier this year explored the answers to that very question. 

In accordance with previous research, the authors found that the Mediterranean diet was effective in reducing CRC tumor growth. The mechanisms that are responsible for this inhibited tumor cell growth include the presence of beta-carotene, which is found in a number of fruits, vegetables, and fish. When beta-carotene interacts with fibroblast activation markers, the fibroblasts repress tumor cell growth in the colon. 

Additionally, anti-inflammatory diets can suppress the growth of CRC tumors via immune system pathways. Tea polyphenols, most commonly found in green tea, add diversity to the gut microbiota by often raising short-chain amino acid levels, which in turn promotes the growth of anti-inflammatory gut bacteria. Elevated levels of these “good bacteria” help to modulate the environment within which CRC develops, and aid the immune system in preventing tumor cell growth and spread.

While it is important to understand these pathways, successful, consistent implementation of preventative diets is the key to unlocking the benefits that come from the pathways. The chart below, adapted from this study, provides a framework for workable diet and lifestyle interventions during the various stages of colorectal cancer treatment, from diagnosis to surgery. Key elements of these interventions involve exercise, protein intake, and supplementation of key nutrients such as omega-3 fatty acids. 

 

Blog 2 in this series can be found here: Tackling Fresh Food Inequality.

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

By Parker Lynch

In a recent study conducted in Korea, it was found that higher levels of alcohol consumption increase an individual’s risk of early-onset colorectal cancer (early-onset CRC), specifically distal colon and rectal cancers. Using data from the Korean National Health Insurance Service, investigators retrospectively compared the drinking habits of 5.7 million Korean adults (all younger than fifty years old) and their corresponding CRC risk. 

The study’s population was split into four groups (after being adjusted for age, sex, smoking status, exercise, income, and comorbidities): 

  1. Nondrinkers (no alcohol consumption)
  2. Light drinkers 
  3. Moderate drinkers 
  4. Heavy drinkers.

During the mean follow-up period of 7.4 years, there were 8,314 cases of early-onset CRC overall. When being compared with the light drinking group, those in both the moderate and heavy drinking categories had a significantly higher CRC risk, though the most intense discrepancy was demonstrated among men. Among men, there was a:

  • 26% increase in risk of distal colon cancer 
  • 17% higher risk of rectal cancer 
  • 29% higher risk of unspecified colon cancer when comparing the heavy versus light drinking group. 

Among women, there was a: 

  • 47% increased risk of distal colon cancer among moderate drinkers 
  • 14% reduced risk of rectal cancer among the light drinkers. 

Overall, this study provides strong evidence that higher levels of alcohol consumption can increase one’s risk of early-onset CRC. 

What Are the Implications of These Findings?

Although the aforementioned study is limited to generalizability among Korean citizens, its findings are still very important to consider when looking at the diverse American population.

In fact, the dangers of excessive alcohol use and its connection to increased CRC risk are not something that American researchers or doctors are unfamiliar with. In an article published by the Ocean Endosurgery Center, less than half of Americans are even aware that alcohol consumption has an impact on cancer risk at all. Additionally, the official Dietary Guidelines for Americans strongly suggests that men should not consume more than two alcoholic drinks per day, while women should drink no more than one. In terms of what is best for an individual’s health, researchers have determined that people really should only be drinking on special occasions.

Many Americans don’t know this information, and there must be a push for increased education and awareness so that people are able to make informed decisions about their own health. Regardless of whether or not people choose to drink after discovering the risks involved, everyone deserves to know the implications of potential lifestyle choices. 

 

Parker Lynch is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

 Photo credit: CHUTTERSNAP on Unsplash

By Deepthi Nishi Velamuri


Colorectal cancer (CRC) is a significant health concern, particularly for those with a family history of the disease. Unfortunately, many existing screening programs overlook this high-risk group. However, a recent study conducted at the University of California Los Angeles (UCLA) has introduced an innovative intervention aimed at improving CRC screening rates in individuals with a family history of CRC. 

The study was presented at Digestive Disease Week 2023.

A Game-Changing Intervention

The researchers at UCLA conducted a study within their large academic health center that already had a screening program for average-risk individuals. They aimed to engage individuals with a family history of CRC who were resistant to screening and determine the effectiveness of the intervention in increasing colonoscopies ordered, scheduled, and completed.

Study participants were divided into two groups:

  1. Group 1 received reminders to schedule a colonoscopy. The attending doctors also received a reminder.
  2. Group 2 received reminders along with educational materials on CRC risk and the colonoscopy procedure, as did their doctors.

Promising Results and Implications

The study included 150 patients, evenly divided between the two groups. The primary outcome showed that both groups had similar rates of completed colonoscopies. However, both groups experienced a significant increase in the number of colonoscopies ordered, scheduled, and completed.

The multicomponent intervention successfully engaged high-risk individuals who had been hesitant about CRC screening. The combination of reminders for doctors and patients proved effective in increasing screening rates. Surprisingly, the additional educational materials did not significantly impact outcomes, suggesting that they may not be necessary in future interventions.

The study’s findings offer hope for improving CRC prevention and control in high-risk individuals with a family history of the disease. By refining and expanding this intervention, we can raise screening rates, detect CRC at an early stage, and potentially save lives.

Take Action

Regular screening is crucial for early detection of CRC. If you have a family history of CRC or are overdue for screening, consult your healthcare provider to discuss the best screening options for you. Together, we can fight CRC and make a meaningful impact on public health.

The Colon Cancer Foundation remains committed to supporting advancements in CRC prevention, early detection, and treatment. Join us in our mission to raise awareness and promote lifesaving screenings. 

Reference-
Impact of a Multicomponent Health System Intervention to Increase Colorectal Cancer Screening Participation in Patients with a Family History of Colorectal Cancer. Jain S, Galoosian A, Badiee J, Meshkat S, Popoola F; Presented at Digestive Disease Week 2023.

 

 Deepthi Nishi Velamuri is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Welcome back to our ongoing series exploring the intricate relationship between colorectal cancer (CRC) and various health conditions. Our previous post uncovered the association between CRC and diabetes mellitus. Today, we embark on a new journey as we unravel the intriguing connection between cardiovascular disease and CRC. Through uncovering the latest research, we aim to shed light on shared risk factors and significant findings that emphasize the importance of addressing both these conditions. 

Shared Risk Factors Identified

A meta-analysis of 84 studies involving over 52 million participants has unveiled a clear association between cardiovascular disease and CRC. The analysis confirmed that individuals harboring risk factors for cardiovascular diseases, such as obesity, high body-mass index, diabetes, and smoking, face an increased likelihood of developing CRC. These shared risk factors act as crucial indicators of potential health complications. 

Intriguingly, the same study revealed a compelling insight: individuals who are obese and exhibit at least one metabolic abnormality, such as hyperglycemia, dyslipidemia, or hypertension, face a 31% higher risk of being diagnosed with CRC. This underscores the significance of managing weight and addressing metabolic health concerns as part of a comprehensive approach to reducing the risk of developing both cardiovascular disease and CRC. 

A study conducted in Taiwan involving a substantial cohort of over 94,000 patients delved into the relationship between cardiovascular disease and CRC prognosis. The findings demonstrated that individuals diagnosed with CRC are more prone to developing cardiovascular disease, particularly coronary heart disease, within the first three years following their CRC diagnosis. This highlights the need for comprehensive health management strategies encompassing cancer treatment and cardiovascular health for CRC patients. 

Uninsured and the Risk of CRC, Cardiovascular Disease 

In a noteworthy cohort study published in June 2022, researchers examined over 197,000 cases of CRC from the SEER database to study the prognosis of CRC patients. They assessed mortality trends due to cardiovascular disease and identified risk factors to develop a predictive model for cardiovascular disease outcomes in this population. The study unveiled a significant risk factor: lack of insurance coverage. It was found that CRC patients without insurance faced a higher likelihood of cardiovascular death than those with health coverage. These findings emphasize the need for further exploration of the link between social determinants of health and health outcomes. 

As we conclude our exploration of the connection between cardiovascular disease and CRC, it becomes increasingly evident that these two conditions share risk factors and impact each other’s prognosis. This knowledge encourages a holistic approach to

healthcare that prioritizes overall well-being and seeks to achieve optimal health outcomes for individuals facing these conditions. By addressing common risk factors, focusing on metabolic health, and implementing comprehensive healthcare strategies, we can strive to minimize the impact of both cardiovascular disease and CRC.

 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

As colorectal cancer (CRC) rates rise globally, especially in the early-onset population, identifying high-level risk factors for developing this disease becomes ever more critical. The link between diabetes and the incidence of colon and rectal cancers was discovered in 1998 and has been well-established since then, as many trials have uncovered the strength of the association between these two diagnoses. 

In 2013, a meta-analysis of 26 observational studies among more than 200,000 patients assessed the relationship between CRC and all-cause mortality (death due to any cause), cancer-specific mortality, and disease-free survival. Interestingly, diabetes was found associated with poorer outcomes for all three categories. A key finding from this study: individuals who have diabetes and CRC have a 17% increased risk of death due to any cause.

A 2017 article on the epidemiology of the association between diabetes and CRC delved into the potential molecular mechanisms of this association and the therapeutic implications of treating both diseases, and found that: 

  • Diabetes mellitus and CRC have many overlapping risk factors
  • Hyperinsulinemia, hyperglycemia, and hyperlipidemia may all play a role in the development of these dual diagnoses
  • Environmental and genetic risk factors may also play a role
  • Promising therapies for treating a dual diagnosis are statins, ACE inhibitors, anti-fibrotic agents, among others

A study among 2023 individuals evaluated the association between type 2 diabetes risk, cholesterol levels, triglyceride levels, and CRC. Additionally, the study assessed the association between Lynch syndrome—which results from a genetic mutation that can lead to CRC—and these other variables, and found that:

  • Individuals with Lynch syndrome, type 2 diabetes, and elevated cholesterol levels had an increased risk of CRC
  • High triglyceride levels in those with Lynch syndrome did not increase CRC risk 
  • Hyperinsulinemia and hyperglycemia in diabetic patients may increase the risk of CRC

A more recent study looked at the clinical and therapeutic implications of diabetes treatment and CRC risk. They found that while not always the case, these drugs often reduced the risk of dual diagnosis. Newer therapies, such as anticancer drugs that target IGF-1R and RAGE receptors (receptors for advanced glycation end products), may also help prevent and treat diabetes-induced CRC. 

It will be essential for future research to continue to explore the mechanisms behind these two diseases and to collaborate to create effective treatments for individuals experiencing dual diagnoses.

 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

The benefits of exercise for overall health and disease prevention are well known. While research overwhelmingly points to physical activity as a protective factor against colorectal cancer, more research is necessary to delineate how the timing of physical activity during one’s life impacts the risk of developing colon cancer. In a recently published study, researchers examined the differences in colon cancer incidence in relation to levels of physical activity at different stages of life. 

Researchers conducted a baseline survey in 1995 and 1996 of adult men and women to measure exposures to moderate-to-vigorous physical activity (MVPA) and several other lifestyle-related factors among nearly 300,000 adults (50-71 years). Study follow-ups ceased in 2011 or following any diagnosis of colon cancer or death. 

In the primary exposure assessment, participants were asked to report and quantify MVPA they had participated in at various stages of their life: at ages 15-18, 19-29, 30-35, and in the previous decade. MVPA levels were measured by time:

  • Rarely or none
  • Less than 1 hour a week
  • 1-3 hours a week
  • 4-7 hours a week
  • Greater than 7 hours per week 

Pattern Recognition and Impact on Colon Cancer Risk

Researchers identified specific patterns of MVPA:

  • Maintaining the same general level of physical activity throughout the life course (whether low, moderate, or high levels of MVPA) 
  • Raising levels of physical activity during the life course, either earlier or later in life (increasers) 
  • Reducing the amount of MVPA over time, either earlier or later in life (decreasers) 

Several key findings emerged from these patterns: 

  • Participants who maintained high MVPA levels throughout their life had a 15% lower risk of colon cancer than those who maintained low MVPA levels throughout their life
  • Participants who increased MVPA levels at a younger age had a 10% reduced risk of colon cancer, and participants who increased MVPA levels at an older age had an 8% reduced risk of colon cancer
  • Decreasing MVPA levels during the life course resulted in a 12% higher risk of colon cancer incidence when compared with individuals who maintained low MVPA levels throughout their life

These findings suggest that individuals who consistently engage in MVPA throughout their life and those who increase MVPA levels during their life have a lower risk of being diagnosed with colon cancer. They provide hope to individuals who may begin their fitness journey later in life. 

Emma Edwards is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Colorectal cancer (CRC), the third most common cancer and the third leading cause of cancer-related deaths in the U.S., is preventable with regular screening. In addition to routine screening, other modifiable risk factors, such as diet, play an important role in lowering the risk of CRC. For example, red and processed meats are associated with an increased risk for CRC, while diets rich in dietary fiber reduce the risk of CRC. 

A recent prospective cohort study discovered that plant-based diets rich in healthy plant foods were associated with a lower risk of CRC in men, and varied based on race, ethnicity, and tumor location. These findings signify the importance of incorporating healthy plant foods into diets and reducing meat consumption to lower the risk of CRC. 

The multiethnic cohort study included 79,952 men and 93,475 women. Three plant-based diet scores were investigated to determine the incidence of invasive CRC:

  • Overall plant-based diet index (PDI)
  • Healthful plant-based diet index (hPDI)
  • Unhealthful plant-based diet index (uPDI)

The participants completed a food frequency questionnaire with over 180 food items. PDI, hPDI, and uPDI were calculated based on scoring methods and defined food groups that included:

  • Healthy plant foods, such as whole grains, fruits, vegetables, vegetable oils, nuts, legumes, tea, and coffee.
  • Less healthy plant foods, such as refined grains, fruit juices, potatoes, and added sugars.
  • Animal foods, such as animal fat, dairy, eggs, fish and seafood, and meat. 

Each food group was associated with specific scores. 

  • High PDI scores demonstrated greater consumption of all types of plant foods. 
  • High hPDI foods showed greater consumption of healthy plant foods and lower consumption of less healthy plant foods. 
  • Higher uPDI scores demonstrated lower consumption of healthy plant foods and greater consumption of less healthy plant foods. 

The study found that a plant-based diet that includes natural, rather than processed, plant-based foods is associated with a reduced risk of CRC in men. For women, however, none of the plant-based diets were significantly associated with CRC risk. For both men and women, the average scores of PDI and hPDI were highest among Japanese Americans and lowest among Native Hawaiians. The mean uPDI was highest in Native Hawaiian men and lowest in African American men and white women. Men with higher scores for PDI and hPDI had a 24% and 21% lower risk of CRC than men with lower scores for those diets, respectively. Furthermore, no significant association was found between risk for CRC and uPDI for men.

These analyses highlight the potential significance of plant-based diets in preventing CRC and suggest that the benefits of plant-based diets can vary based on sex and race/ethnicity. The findings underscore the importance of increasing healthy and less-processed plant foods in our diet and reducing meat consumption to lower the risk of CRC.

 

Sahar Alam is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

Genetic factors play an important role in the development of colorectal cancer (CRC). Some people have inherited genetic syndromes that increase their risk for colon cancer. Genetic testing looks for these inherited syndromes along with changes in DNA that are associated with a greater likelihood of developing cancer. 

What is Genetic Testing for CRC?

Genetic testing looks for changes in your DNA that are known to be associated with an increased risk of cancer. Generally, there are two ways that genetic testing may be used: 

  • Before a person develops cancer to determine their level of risk
  • Following a cancer diagnosis to see if genetic changes may have contributed to the cancer

According to the American Cancer Society, genetic tests can help show if members of certain families have inherited a high risk of CRC due to inherited cancer syndromes such as Lynch syndrome (also known as hereditary non-polyposis colorectal cancer, or HNPCC) or familial adenomatous polyposis (FAP).

Who is Considered “High-Risk”?

Those with a family history of CRC may benefit from speaking to their primary care physician, oncologist, or surgeon about the importance of genetic testing to identify if there was a mutated gene that predisposes them to cancer. You may be a good candidate for genetic testing for CRC if you have:

  • Close family members, such as parents, children, or siblings, who have been diagnosed with CRC
  • Many people on one side of your family who’ve been diagnosed with CRC
  • A personal or family history of CRC diagnosis at a young age
  • A personal or family history of an inherited genetic syndrome that increases CRC risk
  • A personal or family history of multiple cancers
  • A strong family history of CRC or other cancers that are associated with an inherited genetic syndrome
  • More than 10 adenomatous polyps found during CRC screening

What Can I Expect With the Procedure?

If your doctor believes that you’re a good candidate for genetic testing, they’ll likely refer you to a genetic counselor. Genetic testing is typically done using a blood sample. However, it may also use a sample of saliva, cheek cells, or skin. This sample will be sent to a specialized lab that will run the test. After a few weeks, your results will be sent over to your doctor or genetic counselor and you’ll be contacted to discuss your test results and next steps.

How Much Does Genetic Testing for Colon Cancer Cost and is it Covered by Insurance?

Genetic testing can be expensive and can cost between $100 to over $2,000, depending on the nature and complexity of the test. Many insurance providers will cover the cost of genetic testing and genetic counseling if it’s considered medically necessary. 

  • Most private health insurers cover genetic counseling and testing with low- or no out-of-pocket costs for people who meet certain personal or family cancer history criteria.
  • Medicare covers genetic testing for people with a cancer diagnosis who meet certain criteria; you must have a cancer diagnosis to qualify for coverage of genetic testing for an inherited mutation.
  • Medicaid programs cover BRCA genetic counseling and testing for qualifying individuals, including those with a known mutation in the family, or specific personal and/or family history of cancer for all but two states: Alabama and Rhode Island.

Nevertheless, always check with your insurance provider to see what’s covered before getting tested. For additional information about insurance coverage, please visit: Paying for Genetic Services.

 

Kitty Chiu is a Colorectal Cancer Prevention Intern with the Colon Cancer Foundation.

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.