Colorectal Cancer

Last Updated: December 2, 2022

Colorectal cancer (CRC) occurs when tumors form in the lining of the colon or rectum (which together make up the large intestine). Symptoms include a change in bowel habits, fatigue, and unexplained weight loss. CRC is diagnosed after a physical exam of the colon and rectum. It can be treated in a variety of ways, including surgery, immunotherapy, and chemotherapy.

Colorectal Cancer falls under theCancercategory.

What is CRC?

CRC — which occurs when tumors form in the lining of the large intestine — is the third most common type of cancer in the world, and the second leading cause of cancer-related death.[1] Like other digestive cancers, the risk of developing CRC is higher in people who smoke, drink alcohol, are sedentary, or have obesity. Other risk factors include old age, a family history of CRC, a personal history of CRC or high-risk adenomas (polyps made of abnormal cells), or having inflammatory bowel disease. The prognosis for CRC depends on the patient’s general health, whether the cancer has spread to other parts of the body or blocked the colon, and whether cancerous cells remain after treatment.[2]

What are the main signs and symptoms of CRC?

Common signs and symptoms of CRC include a change in bowel habits (such as bloody stool, unusually narrow stool, diarrhea, or constipation), bloating, gas pains, fatigue, vomiting, and unexplained weight loss. However, CRC may not cause symptoms, which is why colorectal cancer screening is recommended for everyone over the age of 45.[2]

How is CRC diagnosed?

A variety of tests are used to examine the intestinal lining and stool samples. During a colonoscopy or sigmoidoscopy, a thin tube with a camera is inserted into the rectum to allow the doctor to see the intestinal lining and collect biopsies for testing. Fecal occult blood tests are used to detect blood in the stool (which may not be visible to the naked eye). DNA stool tests detect changes in the genetic material of intestinal cells, which can also be a sign of CRC. If a patient is diagnosed with CRC, other tests like x-rays and CAT scans are performed to determine whether the cancer may have spread to other areas.[2]

What are some of the main medical treatments for CRC?

Surgery is the most common form of treatment, and can often cure CRC if the cancer is caught early enough. Cancerous cells and tissue can also be destroyed with heat via radiofrequency ablation, extreme cold via cryosurgery, or x-rays via radiation therapy. Chemotherapy drugs can be taken orally or intravenously, and can be more systemic (affecting the entire body) or regional (affecting one area) depending on the location of the cancer. Finally, immunotherapy can change the activity of the patient’s immune system, causing it to attack and destroy cancer cells.[2]

Have any supplements been studied for CRC?

A small body of evidence suggests that berberine supplementation may reduce the recurrence rate of colorectal adenomas, which commonly evolve into CRC over time.[1] When added to chemotherapy treatment, some studies showed that some herbs used in Traditional Chinese medicine could improve quality of life, reduce some chemotherapy side effects, and enhance the tumor response to certain treatments (but the quality of evidence was low and results were inconsistent.)[3][4][5] Probiotics and synbiotics could reduce infections and complications after CRC surgery.[6] Vitamin D supplementation has also been studied, but conflicting study results prevent any conclusions about its ability to protect against CRC.[7][8]

How could diet affect CRC?

A person’s diet has a significant impact on their risk of CRC. Prudent dietary patterns — such as the Dietary Approaches To Stop Hypertension Diet (DASH) diet — have been associated with a roughly 20% reduction in the risk of CRC.[9][10] These diets are high in fiber-rich whole grains, fruits, vegetables, and legumes, but low in red or processed meat and refined sugar.[11][12]

Vegetarian and pescatarian diets are also associated with a lower risk of CRC compared to diets that include red meat.[13] Garlic, cheese, and yogurt may also reduce the risk of developing CRC.[14][15]

With the exception of wine, drinking more than one alcoholic beverage per day is associated with increased CRC risk.[16][17]

Mediterranean-style diets and diets high in dairy or nuts are associated with lower mortality and a better prognosis in people with CRC.[18][19][20] Diets high in processed meat, sugar, and soft drinks are associated with a worse prognosis.[18]

Are there any other treatments for CRC?

Though exercise isn’t considered a treatment for CRC, engaging in at least three hours of moderate physical activity per week can increase survival rates in patients with non-metastatic CRC (cancer that hasn’t spread to other areas).[21] Cognitive interventions — such as cognitive behavioral therapy or relaxation techniques — can improve cancer-related fatigue and both short- and long-term quality of life, while social support groups can improve short-term quality of life.[22] Immunonutrition combines enteral or parenteral nutrition formulas with additional arginine, glutamine, and omega-3 fatty acids, and could improve post-operative recovery compared to the plain formulas.[23]

What causes CRC?

The exact cause of CRC is unknown, but it likely results from an interaction between lifestyle and genetic factors that causes unregulated intestinal cell division. When the process of cell division isn’t controlled properly, the cells can form a tumor. Some evidence suggests that oxidative stress damages cellular DNA, proteins, and lipids, causing mutations that lead to unregulated growth.[24] Finally, Lynch syndrome is an inheritable genetic mutation that significantly increases the risk of developing CRC.

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  1. ^Fang S, Guo S, Du S, Cao Z, Yang Y, Su X, Wei WEfficacy and safety of berberine in preventing recurrence of colorectal adenomas: A systematic review and meta-analysis.J Ethnopharmacol.(2022-Jan-10)
  2. ^Colon Cancer Treatment (PDQ) - Health Professional Version, Bethseda, MD: National Cancer Institute at the National Institutes of Health, USA(October 14, 2022)
  3. ^
  4. ^Chen P, Ni W, Xie T, Sui XMeta-Analysis of 5-Fluorouracil-Based Chemotherapy Combined With Traditional Chinese Medicines for Colorectal Cancer Treatment.Integr Cancer Ther.(2019)
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  6. ^Veziant J, Bonnet M, Occean BV, Dziri C, Pereira B, Slim KProbiotics/Synbiotics to Reduce Infectious Complications after Colorectal Surgery: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.Nutrients.(2022-Jul-26)
  7. ^Emmanouilidou G, Kalopitas G, Bakaloudi DR, Karanika E, Theocharidou E, Germanidis G, Chourdakis MVitamin D as a chemopreventive agent in colorectal neoplasms. A systematic review and meta-analysis of randomized controlled trials.Pharmacol Ther.(2022-Sep)
  8. ^Huang D, Lei S, Wu Y, Weng M, Zhou Y, Xu J, Xia D, Xu E, Lai M, Zhang HAdditively protective effects of vitamin D and calcium against colorectal adenoma incidence, malignant transformation and progression: A systematic review and meta-analysis.Clin Nutr.(2020-Aug)
  9. ^Garcia-Larsen V, Morton V, Norat T, Moreira A, Potts JF, Reeves T, Bakolis IDietary patterns derived from principal component analysis (PCA) and risk of colorectal cancer: a systematic review and meta-analysis.Eur J Clin Nutr.(2019-Mar)
  10. ^Hadith Tangestani, Asma Salari-Moghaddam, Hamid Ghalandari, Hadi EmamatAdherence to the Dietary Approaches to Stop Hypertension (DASH) dietary pattern reduces the risk of colorectal cancer: A systematic review and meta-analysisClin Nutr.(2020 Feb 7)
  11. ^Chang H, Lei L, Zhou Y, Ye F, Zhao GDietary Flavonoids and the Risk of Colorectal Cancer: An Updated Meta-Analysis of Epidemiological Studies.Nutrients.(2018-Jul-23)
  12. ^Oh H, Kim H, Lee DH, Lee A, Giovannucci EL, Kang SS, Keum NDifferent dietary fibre sources and risks of colorectal cancer and adenoma: a dose-response meta-analysis of prospective studies.Br J Nutr.(2019-Sep-28)
  13. ^Solange Parra-Soto, Danay Ahumada, Fanny Petermann-Rocha, Jirapitcha Boonpoor, Jose Lara Gallegos, Jana Anderson, Linda Sharp, Fiona C Malcomson, Katherine M Livingstone, John C Mathers, Jill P Pell, Frederick K Ho, Carlos Celis-MoralesAssociation of meat, vegetarian, pescatarian and fish-poultry diets with risk of 19 cancer sites and all cancer: findings from the UK Biobank prospective cohort study and meta-analysisBMC Med.(2022 Feb 24)
  14. ^Zhang K, Dai H, Liang W, Zhang L, Deng ZFermented dairy foods intake and risk of cancer.Int J Cancer.(2019-May-01)
  15. ^Zhou X, Qian H, Zhang D, Zeng LGarlic intake and the risk of colorectal cancer: A meta-analysis.Medicine (Baltimore).(2020-Jan)
  16. ^Zhong L, Chen W, Wang T, Zeng Q, Lai L, Lai J, Lin J, Tang SAlcohol and Health Outcomes: An Umbrella Review of Meta-Analyses Base on Prospective Cohort Studies.Front Public Health.(2022)
  17. ^Xu W, Fan H, Han Z, Liu Y, Wang Y, Ge ZWine consumption and colorectal cancer risk: a meta-analysis of observational studies.Eur J Cancer Prev.(2019-May)
  18. ^Castro-Espin C, Agudo AThe Role of Diet in Prognosis among Cancer Survivors: A Systematic Review and Meta-Analysis of Dietary Patterns and Diet Interventions.Nutrients.(2022-Jan-14)
  19. ^Jin S, Kim Y, Je YDairy Consumption and Risks of Colorectal Cancer Incidence and Mortality: A Meta-analysis of Prospective Cohort Studies.Cancer Epidemiol Biomarkers Prev.(2020-Nov)
  20. ^Fadelu T, Zhang S, Niedzwiecki D, Ye X, Saltz LB, Mayer RJ, Mowat RB, Whittom R, Hantel A, Benson AB, Atienza DM, Messino M, Kindler HL, Venook A, Ogino S, Ng K, Wu K, Willett W, Giovannucci E, Meyerhardt J, Bao Y, Fuchs CSNut Consumption and Survival in Patients With Stage III Colon Cancer: Results From CALGB 89803 (Alliance).J Clin Oncol.(2018-Apr-10)
  21. ^Choy KT, Lam K, Kong JCExercise and colorectal cancer survival: an updated systematic review and meta-analysis.Int J Colorectal Dis.(2022-Aug)
  22. ^Dun L, Xian-Yi W, Si-Ting HEffects of Cognitive Training and Social Support on Cancer-Related Fatigue and Quality of Life in Colorectal Cancer Survivors: A Systematic Review and Meta-Analysis.Integr Cancer Ther.(2022)
  23. ^Xu J, Sun X, Xin Q, Cheng Y, Zhan Z, Zhang J, Wu JEffect of immunonutrition on colorectal cancer patients undergoing surgery: a meta-analysis.Int J Colorectal Dis.(2018-Mar)
  24. ^Zhang X, Zhao H, Man J, Yin X, Zhang T, Yang X, Lu MInvestigating Causal Associations of Diet-Derived Circulating Antioxidants with the Risk of Digestive System Cancers: A Mendelian Randomization Study.Nutrients.(2022-Aug-08)
Examine Database References
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  3. Subjective Well-Being - Norman K, Stübler D, Baier P, Schütz T, Ocran K, Holm E, Lochs H, Pirlich MEffects of creatine supplementation on nutritional status, muscle function and quality of life in patients with colorectal cancer--a double blind randomised controlled trialClin Nutr.(2006 Aug)
  4. Colorectal Cancer Risk - Zick SM, Turgeon DK, Vareed SK, Ruffin MT, Litzinger AJ, Wright BD, Alrawi S, Normolle DP, Djuric Z, Brenner DEPhase II study of the effects of ginger root extract on eicosanoids in colon mucosa in people at normal risk for colorectal cancerCancer Prev Res (Phila).(2011 Nov)
  5. Colorectal Cancer Risk - Oka S, Tanaka S, Yoshida S, Hiyama T, Ueno Y, Ito M, Kitadai Y, Yoshihara M, Chayama KA water-soluble extract from culture medium of Ganoderma lucidum mycelia suppresses the development of colorectal adenomasHiroshima J Med Sci.(2010 Mar)
  6. Colorectal Cancer Risk - Gorham ED, Garland CF, Garland FC, Grant WB, Mohr SB, Lipkin M, Newmark HL, Giovannucci E, Wei M, Holick MFOptimal vitamin D status for colorectal cancer prevention: a quantitative meta analysisAm J Prev Med.(2007 Mar)
  7. Colorectal Cancer Risk - Robert E Carroll, Richard V Benya, Danielle Kim Turgeon, Shaiju Vareed, Malloree Neuman, Luz Rodriguez, Madhuri Kakarala, Philip M Carpenter, Christine McLaren, Frank L Meyskens Jr, Dean E BrennerPhase IIa clinical trial of curcumin for the prevention of colorectal neoplasiaCancer Prev Res (Phila).(2011 Mar)
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  9. Colorectal Cancer Risk - Moazzen S, Dolatkhah R, Tabrizi JS, Shaarbafi J, Alizadeh BZ, de Bock GH, Dastgiri SFolic acid intake and folate status and colorectal cancer risk: A systematic review and meta-analysis.Clin Nutr.(2018-Dec)
  10. Inflammation - Rotovnik Kozjek N, Kompan L, Soeters P, Oblak I, Mlakar Mastnak D, Možina B, Zadnik V, Anderluh F, Velenik VOral glutamine supplementation during preoperative radiochemotherapy in patients with rectal cancer: a randomised double blinded, placebo controlled pilot studyClin Nutr.(2011 Oct)
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