Colorectal cancer is one of the most preventable cancers, yet it is also one of the most common and deadly cancers worldwide. With few early-stage symptoms, many are stunned to hear their five-foot-long large intestine has a small chance of repair. Although polite society tends to avoid the topic of processing and expelling waste material, Symbios Health believes the power of knowledge can be life-changing.

The Colon’s Large Role in Digestion and Health

As part of the digestive system, this essential organ in the gastrointestinal (GI) tract processes indigestible food material (chyme) from the small intestine and transports the waste material toward the rectum for elimination. While the large intestine absorbs liquid to compact the chyme into easily expellable feces, it also maintains gut health with bacterial cultivation and absorption of nutrients and electrolytes into the bloodstream. Our body’s health significantly benefits from the colon’s role in:

Nutrient Absorption

• The colon aids in absorbing vital nutrients, including vitamins K and B (such as biotin).
• These vitamins are produced through the fermentation of trillions of bacteria residing in the colon.

Water Absorption

• The colon absorbs water through osmosis, driven by an osmotic gradient established by electrolyte absorption.

Electrolyte Balance

• The colon helps maintain potassium levels by absorbing or secreting potassium based on the body’s needs and the lumen’s concentration.
• Sodium is absorbed via sodium channels and creates an electrochemical gradient that also facilitates chloride ion exchange for bicarbonate ions, helping regulate acid-base balance.

The colon gets most of its blood from the mesenteric artery, with veins running alongside it. It drains lymph fluid through nearby lymph nodes. Nerves that control digestion, like the vagus and pelvic nerves, help manage the colon’s functions. The colon also produces digestive hormones and alkaline mucus.

The large intestine constitutes about one-fifth of our GI tract and is divided into four primary sections.

Right Colon: Its primary function is to absorb water and nutrients.

1. Cecum and ascending colon: This initial segment absorbs fluids and salts.
2. Transverse colon: The central region where bacteria further break down food materials.

Left Colon: Its central role is to store and excrete feces.

3. Descending colon: This downward section stores materials ready for excretion.
4. Sigmoid colon:The S-shaped segment is crucial for waste storage and connects to the rectum.

Each section plays a specific role in absorbing water, vitamins, and electrolytes from waste material, contributing to overall health.

Understanding Colorectal Cancer

Disruption in the colon’s function can lead to severe health issues, such as colorectal cancer (CRC), a multifactorial disease that begins in the colon or rectum. CRC may be present without symptoms and is often overlooked as it develops into advanced stages.

Each case of CRC is unique, yet common symptoms may include:

• Persistent changes in bowel habits (diarrhea, constipation),
• Blood in the stool or rectal bleeding,
• Abdominal discomfort, such as cramps, gas, or pain,
• Weakness or fatigue, and/or
• Unexplained weight loss.

CRC’s etiology is complex, but a healthy lifestyle can significantly reduce your risk factors, and understanding potential causes can help with early detection.

Formation of Colorectal Cancer

Most cases of CRC typically start with small benign polyps (noncancerous clumps of cells) on the lining of the colon or rectum that develop into cancer over time. The polyp formation originates in the innermost layer (the mucosa) and can grow outward. As the cancer cells penetrate the wall, they can invade blood vessels or lymph vessels, enabling them to travel to nearby lymph nodes or distant parts of the body. The stage of colorectal cancer is determined by how deeply it infiltrates the wall and whether it has spread malignant (cancerous) cells outside the colon or rectum.

Causes of CRC Formation

Genetic Mutations (Inherited or Acquired)

Genomic instability, such as increased DNA mutations, is strongly linked to colorectal cancer (CRC) development. In about 85% of CRC cases, chromosomal instability is the most common cause, while the remaining 15% are linked to microsatellite instability (MSI). Microsatellites are short, repeated DNA segments, and they can signal problems with mismatch repair (MMR) genes, which are responsible for fixing DNA errors. When these genes malfunction, it can lead to many cancer-causing mutations, especially in genes like MLH1, MSH2, MSH6, PMS2, and EpCAM. These gene mutations are associated with Lynch syndrome, an inherited condition that dramatically increases cancer risk, often before age 50. Lynch syndrome is autosomal dominant, meaning it is easily passed down and speeds the development of cancer (2 years instead of 10). It also raises the chance of cancer returning to 40% within 20 years after the initial tumor is removed.

Inflammatory Bowel Diseases 

Conditions such as Crohn’s disease or ulcerative colitis can contribute to CRC. Research indicates that 3-5% of ulcerative colitis patients will develop CRC, with the incidence exceeding 10% in those with the condition for over 20 years.

Family History of Colon Cancer or Polyps

Approximately 15-40% of colon cancers originate from colonic polyps, which have a precancerous progression of 2-5 years. Adenomas (polyps) smaller than 1 cm in diameter have less than a 2% chance of becoming cancerous, while those larger than 3 cm have more than a 40% chance.

The epithelial cells lining the colon and rectum can experience hyperplasia (an increase in the number of cells), which can progress to mild or severe abnormal hyperplasia. Polyps, also called adenomas (benign tumors), may sometimes form. These adenomas have the potential to develop into cancer. The process usually starts when carcinogenic (cancer-causing) factors damage DNA, leading to the growth of malignant cells. The stages include normal epithelial hyperplasia, atypical hyperplasia, formation of adenomas (polyps), carcinoma in situ (early-stage cancer), and invasive carcinoma (advanced cancer).

Gastrointestinal Stromal Tumors (GISTs)

GISTs, benign or malignant, originate from nerve cells in the gastrointestinal tract wall and are commonly found in the stomach and small intestine. Carcinoid tumors can develop from hormone-producing cells in the intestine.

Testing and Diagnosis for Colon Cancer

Early detection of colon cancer significantly improves treatment outcomes. Several screening options are available to detect colorectal cancer and precancerous polyps. Regular screenings are recommended to start at age 45 for average-risk individuals and at age 35 for those with a higher risk, which includes African Americans, those with genetic conditions like Lynch syndrome, or a family history of colon cancer (screening starts at age 35 or 10 years younger than the earliest diagnosis in the family).

Screening Options

Colonoscopy

While a colonoscopy provides an accurate overview of the colon for CRC diagnosis, it is also commonly avoided due to its invasiveness. A colonoscopy uses a camera inserted into the rectum with a flexible tube, allowing doctors to examine the colon. If polyps or abnormal tissue are found, they can be removed during the procedure. The procedure can be repeated every ten years if no abnormalities are found. If polyps or other issues are present, a colonoscopy may be recommended again in five years. A flexible sigmoidoscopy is like a colonoscopy but only examines the colon’s lower part.

Blood Tests 

The FDA has deemed CRC blood tests viable for preliminary CRC screening. Blood work at annual well exams incorporates a less invasive method to check for potential CRC. CRC blood tests have shown an 83% detection rate and a 90% detection rate for neoplasms (abnormal growths) and circular tumor DNA (ctDNA). Symbios Health’s advanced lab equipment can detect health abnormalities and check specific digestive enzymes to identify the colon’s initial buildup of mutagenic cellular activity with the following blood tests:

• A complete blood count (CBC) can detect anemia (low red blood cell count), suggesting chronic colon bleeding due to a tumor. While anemia itself doesn’t confirm cancer, it can be a sign that further investigation is needed.
• Liver function tests may indicate that cancer has advanced since colon cancer can spread to the liver. While abnormal liver functions do not diagnose colon cancer, they can initiate the need for further testing.
• Carcinoembryonic antigen (CEA) is a protein that may be elevated in people with colon cancer. A CEA test helps monitor cancer progression or recurrence after treatment.

Stool Tests 

• The fecal immunochemical test (FIT) analyses a stool sample for hidden blood, which can indicate the presence of cancer. For average-risk individuals, this test is repeated annually.
• Guaiac-based fecal occult blood test (gFOBT) uses a chemical reaction to check for hidden blood in the stool once a year.
• A stool DNA test (e.g., Cologuard) detects abnormal DNA and blood in the stool, which can indicate cancer or large polyps. For those at average risk, it is repeated every three years.

CT Colonography (Virtual Colonoscopy)

A CT scan creates detailed images of the colon and rectum. If polyps or suspicious areas are found, a standard colonoscopy is required for removal or biopsy. For average-risk individuals, this procedure should be repeated every five years.

Risk Factors of Colorectal Cancer

While some factors, such as age and genetic conditions, are beyond control, many lifestyle choices can significantly affect the likelihood of developing CRC. Improve your odds by understanding and addressing the following:

• Sedentary Lifestyle: A lack of regular physical activity contributes to poor digestion, hormonal imbalances, weight gain, inflammation, and sluggish blood circulation, raising the risk of CRC. Regular exercise can remarkably aid in preventing CRC.
• Obesity: Being overweight or obese not only increases the chance of developing colon cancer but also raises the risk of dying from it.
• Smoking and Excessive Alcohol Consumption: Both smoking and drinking alcohol excessively are linked to a higher chance of colon cancer, as they can damage the cells lining the colon.
• Unhealthy Diet: Diets high in processed foods, especially processed meats like bacon, hot dogs, deli proteins, and sausages, are known to elevate the risk of CRC.
• Medical Conditions: Diseases such as diabetes and metabolic syndrome (a cluster of conditions that occur together) can increase the risk of colorectal cancer by affecting insulin and inflammation levels in the body.

Symbios’ foundation is centered on helping you stay informed and proactive to build the best version of you! Start supporting your body’s defense system with our Seven Pillars of Health, which encourages enriching nutrition, functional fitness, restorative sleep, and more. Symbios Nutrition can help you adopt a fiber-rich, low-carb diet loaded with unprocessed proteins that help you maintain a healthy weight. Plus, you can stay active at SymbiosFIT with friendly classes for all fitness levels. You are a valued part of our Symbios family, and together, we can take steps to prevent colorectal cancer and ensure a healthier future.

References

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