The Silent Threat: Common Types of Intestinal Cancers

Colorectal cancer is highly influenced by lifestyle, body fatness, and dietary patterns. Individuals who eat a typical Western diet that is high in fat and ultra-processed foods, lack physical activity, and consume alcohol and smoke are at a higher risk of developing this type of cancer. However, it can also be influenced by comorbidity and genetics as well. It is the third most occurring cancer in men and second most occurring cancer in women; it encompasses approximately 11% of cancer diagnoses worldwide, with developed countries leading the way in new diagnoses. Modern technology, like endoscopic procedures, has assisted in earlier detection, which has helped reduce the mortality rate despite it being the second leading cause of cancer-related deaths worldwide.

Other Intestinal Cancers: Less Common but Serious

Other cancers that can affect the GI tract, like intestinal cancer, gastric cancer, liver cancer, pancreatic cancer, and gallbladder cancer, are on the rise, too. Like colorectal cancer, these cancers are also highly influenced by lifestyle and poor dietary choices, leading to obesity and the development of chronic diseases.

Gastric cancer is now ranked fifth among all malignant tumors and is a big concern among people living in developed countries. Outside of diet and lifestyle choices, other factors like smoking, alcohol intake, and infections like H.pylori are also risk factors for developing gastric cancer. Intestinal cancers like duodenal adenocarcinoma, carcinoid tumors, lymphomas, and sarcomas can also occur but are less likely compared to the above-mentioned cancers. These types of cancers are also more difficult to detect.

Recognizing the Red Flags: Warning Signs of Intestinal Cancers

Changes in Bowel Habits: A Common Warning Sign

Maybe the first sign you recognize is a change in bowel habits. Many people tend to ignore this warning sign because it can be associated with varying causes like IBS, stress/anxiety, food intolerances, etc. However, this could be the first sign that appears to alert you of a potential cancer diagnosis. If you have a significant change in stool consistency, color, frequency, amount, or shape (thin stool) and it lasts longer than a couple of weeks, you should follow up with your doctor. Additional testing is needed to rule out potential causes, including cancer. One study identified that out of 579 subjects, only 5% noted a change in bowel habits that alerted them there may be something wrong. A majority of subjects remained asymptomatic. However, this could be due to normalcy of not having regular bowel movements.

Bleeding in the Digestive Tract: When to Seek Medical Attention

A big red flag is blood in the stool- if you notice bright red blood or black tarry stool, that could indicate active or old bleeding in the GI tract, which would warrant further investigation by a medical provider. The same study previously reported a 23% incidence rate of bloody stool as a symptom of colorectal cancer in 579 subjects. Also, if you start experiencing vomiting and it contains blood, this is a sign you should seek medical assistance. Do not ignore blood coming out of your GI tract!

Other Potential Symptoms: Persistent Abdominal Discomfort, Weight Loss, and Fatigue

Other common symptoms include abdominal pain/discomfort and cramping. This could be ongoing/consistent pain, or it may be mainly after eating/postprandial pain. Sometimes, people may experience a lack of appetite, early satiety (feeling full quickly after a few bites), and taste aversions. Unintended weight loss and fatigue are also signs that something is off. Typically, most people with cancer will begin to experience more of these symptoms as time goes on. This is why it is crucial to pay attention to changes in your feelings and health so you can seek help promptly.

Prevention and Early Detection: Your Best Defense Against Intestinal Cancers

Lifestyle Factors: Diet, Exercise, and Reducing Risks

Our BEST defense against cancer is our lifestyle choices. Make sure to eat a plant-based, whole-food diet. Avoid known carcinogens like alcohol and smoking. Also, limit/avoid ultra-processed foods and beverages high in sugars, chemicals, and other additives that are not beneficial/necessary for our health. Aim to get at least 30 grams of fiber daily in your diet from non-starchy vegetables and fruits. Consume adequate lean protein from reputable food sources (grass-fed beef, pasture-raised chicken, wild-caught fish, beans, whole grains like quinoa); limit red meat intake to 2 times weekly or 18 oz weekly and avoid processed and cured meats like lunch meats, breakfast meats and hotdogs that contain nitrates. If you’re looking for a great diet, check out the Mediterranean diet- many studies have shown the benefits of this low anti-inflammatory diet for health risk reduction.

Get outside and get active- avoid sedentary behaviors and activities. A great starting place is using your hour lunch break and taking a 30-minute walk outside. Participate in strength training exercises to build muscle mass, burn fat, and prevent bone demineralization.  Current guidelines from the American Institute For Cancer Research suggest 45-60 minutes of moderate or 30 minutes of vigorous activity daily for cancer protection. If you’re overweight or obese, reduce your weight to improve your health. Exercise at any body size provides protective measures against cancer development. Talk with a dietitian to learn more about appropriate goals and attainable ways to achieve your goals.

Screening and Early Detection: The Role of Colonoscopies

The American Cancer Society recommends that individuals 45 years old and older get routine screening for colon cancers via stool testing (FIT, gFOBT, or MT-sDNA) or visual examination (colonoscopy, sigmoidoscopy, or CT colonography). Screening is also appropriate for anyone noticing changes in bowel habits, familial history of colon cancer/GI malignancy, and/or other varying factors like history of IBD, radiation therapy to the abdomen, and history of polyps. Furthermore, current recommendations do not recommend routine screening for individuals over 85 years of age; it is more based on one's preferences and desires.

Knowing Your Family History: Genetic Predisposition and Intestinal Cancers

It is very common for medical practitioners to ask about family medical history. This is very important when it comes to cancer incidence, as individuals with a family history of cancer might have a higher chance of cancer development. Make sure to talk with family members and ask them questions regarding their health regarding colon cancer or other GI malignancies. This could be key to reducing your chances of developing cancer and/or identifying a malignancy in early stages.

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