Colon Cancer
History of Colon Cancer
Colorectal cancer is the third leading cause of cancer deaths in the world. It is an adenocarcinoma of glandular epithelial cell origin that affects the cells of the large intestines. It arises due to genetic or epigenetic mutations of specific epithelial cells of the colon. The hyperproliferative nature of the mutated cells gives rise to a benign adenoma can metastasize to various parts of the body over time. Due to an increase in emphasis on screening for cancers, colon cancer is detected in early stages before causing severe symptoms or before malignant cells metastasize to different organs. Positive family history of colorectal carcinoma increases the likelihood of having colon cancer (Byers et al., 2018). Hereditary conditions such as familial adenomatous polyposis and Lynch syndrome brings about an extremely high risk of colon cancer.
Causes of Colon Cancer
The majority of the colon cancers are related to the positive history of adenomatous polyps. Rawla Sunkara & Barsouk, (2019) observes that the polyps are characterized by both normal and abnormal appearing cells of epithelial origin. These abnormal cells hyperproliferate and later degenerates to form adenocarcinomas. Genetic predisposition of an individual to colon cancer and polyposis increases the risk of colorectal carcinoma. Numerous adenomatous polyps often develop to adenocarcinoma. There is a genetic relationship, thus known as familial adenocarcinoma. To lower the risk of adenomatous polyps developing into colon adenocarcinoma, the Food and Drugs Act approves use celecoxib for six months to mitigate their course. Colon cancer can also originate from the non-polyposis origin, which is another group of colon cancer syndrome. They are referred to as hereditary non-polyposis colorectal cancer (HNPCC). They are associated with a genetic abnormality, which can be tested during genetic screening. Carriers of abnormal genes require genetic counseling and consistent screening to detect premalignant and cancerous tumors to prevent metastasis. Other conditions have been attributed to the development of colon cancers. These include toxic megacolon or Crohn’s disease and ulcerative colitis. Breasts, ovarian, and uterine cancer are among the factors that are associated with colon cancers (Rawla Sunkara & Barsouk, 2019). The first degree relative with a positive history of colorectal cancer is related to the risk of colon cancer.
Risk Factors Associated with Colorectal Carcinoma
The factors associated with colon cancer are classified as either modifiable or non-modifiable factors. Several environmental and lifestyle non-modifiable related factors include the following.
- Age – The likelihood of colon cancer diagnosis increases as an individual advance in age. Progressive inflation from the 40s to 50s raises the risk of colon cancers sharply. However, in the United States, the populations at high risks are between 20 to 49 years.
- Personal history of adenomatous polyps – tubular and villous adenomas of neoplastic origin is a precursor for colorectal carcinoma. The lifetime risk of developing colorectal adenocarcinomas in the U.S. is about 19%. Generally, about 95% of sporadic colorectal cases (Byers et al., 2018). Early detection and excision of adenomatous cells before malignant transformation reduces the risk of developing colon cancer.
- Personal history of Inflammatory Bowel Syndrome – inflammatory bowel disease represents Crohn’s disease and ulcerative colitis. Ulcerative colitis causes inflammation of the colon and rectum. These lead to a change in characteristics of epithelial cells, thus increasing the risk of colorectal cells (Rawla Sunkara & Barsouk, 2019). The overall uncertainty in persons with inflammatory bowel disease increases the risk of colorectal carcinoma.
- Inherited genetic risks – approximately 5-10% of colorectal cancer cases are related to genetic inherited malignant cells, mostly familial adenomatous polyposis and hereditary non-polyposis colorectal cancer.
Other factors that increase the risk of colon cancer include nutritional practices. Changes in food habits might reduce up to 70% of the colon cancer burden. Diets high in fat, primarily animal fats, are major risk factors for colorectal cancers. The high meat content is attributed to colon cancer prevalence. Lifestyle habits like cigarette smoking, apart from small cell lung carcinoma, are attributed to the early onset of colon cancer. Smokers have shown an increased formation and growth of malignant cells. Heavy consumption of alcohol is also associated with an increase in the prevalence of colon cancers (Kuldipsinh & Yadav, 2017). Reduced physical activity and obesity account for about a third of all colorectal carcinomas.
Trends Regarding Colon Cancer
Colon cancer is one of the most precise markers of both epidemiological and nutritional transition in studies of incidence rates of colon cancers. A continuous update project by world health organization is the basis of evidence-based prevalence and causes related to colon cancer cases. Epidemiological studies of colon cancers have been done to determine the incidence, mortality rates, survival, and related risk factors to enable health care institutions to plan care and treatment modalities to reduce the burden of cancer death, especially colon cancers. According to Rawla Sunkara & Barsouk (2019), colon carcinoma is now the fourth most incident cancer in the world. Together with rectal cancer, they contribute 11% of all cancer cases diagnoses. About 1.09 million new cases are estimated to be diagnosed in 2018. Together with colorectal cancer, they make up about 1.8 million cases. Age-standardized incidence rates show a general increase in the number of female numbers than males. Developed countries have shown the highest risks of colon and rectal cancers.
The number of deaths associated with colorectal cancer makes it the second of the most deadly cancers in the world. Colon cancer alone is the fifth in rank on most deadly diseases globally. Global prevalence rates show high male mortality rates in Asian countries like Saudi Arabia, Oman, and UAE. The majority of Female deaths have been recorded in Japan, Portugal, Spain, and Russia (Rawla Sunkara & Barsouk, 2019). The high numbers call for global intervention measures to mitigate the dangers posed by the disease.
The relationship between trends in mortality rates global incidence rates is comprised of medium nations, high and highest human developmental index depending on improvement rates of disease control. (Byers et al., 2018) acknowledges that mortality rates have significantly decreased over time. Improvement in treatment modalities has led to an increase in survival. The global health organizations have studied etiology and invested thwarting modifiable factors thus reducing the total numbers of colon cancers
Prevention of Colon Cancer
There is no specific way of preventing colon cancer as per se. However, there is a thing that could be done to lower the risk of colorectal cancer by changing modified factors. Various measures include the following. According to Smith et al. (2018), colorectal carcinoma screening looks for malignant and premalignant cells in patients who have no signs and symptoms of a disease. This leads to early detection, thus treatment of colon cancer. Increasing physical activities modifies body weight and prevents the development of an obese body. Having a healthy weight and reducing the amount of meat and animal fats consumed can lead to better results in the prevention of colon cancer.
Lifestyle modification measures can help reduce cancer incidences. Avoiding excess alcohol consumption lowers the risk of colon cancer. Smith et al. (2018) say that cigarette smoking is the primary risk factor known for colorectal cancer. Quitting smoking may reduce the gross risk factors for colon cancer as well as other types of cancers like small cell lung carcinoma. Increasing dietary intake of minerals like calcium has proven decisive in the prevention of colon cancer. Despite the few studies to support that, an increase in dietary magnesium has reduced colorectal cancer risks, especially in women. Early treatment of inflammatory bowel disease using non-steroidal anti-inflammatory drugs (NSAIDs) reduces the risks posed by inflammatory bowel disease precipitation to colon cancer. Low doses of aspirin have been beneficial over time to prevent ulcerative colitis and Crohn’s disease. In postmenopausal women, hormone replacement therapy reduces the risk for the development of colorectal cancer, which is more prevalent in this group of women.
Treatment of Colon Cancer
Treatment approaches to colon cancer are mainly made according to stages of colon cancer. However, Yde et al. (2018) argue that the primary treatment is usually surgical removal of the part affected early enough before metastasis has taken place. Chemotherapy is done after surgery, known as adjuvant treatment, for at least six months. In stage 0 of colon cancer, partial colectomy is prescribed. Cancer has not gone beyond the inner lining of the colon. Therefore local surgery if the only surest treatment modality. In the first stage, colon cancer has grown deeper into layers but has not metastasized to regional lymph nodes. Treatment depends on the cause, for example, if cancer is secondary to polyps, surgical excision of the polyp is done. More surgeries may be done if polyps were in high grade. In case it was a non-polyps partial colectomy. It is efficient without more treatment. Since stage 2, colon cancer has metastasized to neighboring lymph nodes. Treatment involves partial colectomy and removal of at least 12 lymph nodes along with it. Chemotherapy follows the procedures with the main drugs being 5-FU, oxaliplatin, capecitabine, and leucovorin (Yde et al., 2018). Stage 3 colon cancer has spread to all surrounding lymph nodes but has not metastasized to other organs. Partial colectomy to the part of the colon affected, and all lymph nodes are done, followed by chemotherapy. The final fourth stage of colon cancer is diagnosed by malignant cells having metastasized to distant organs and tissues like peritoneum, liver, brain, spinal cord, among many other parts. Surgery is unlikely to cure this cancer; therefore, chemotherapy and palliative care are offered. However, if metastases have not affected many organs, total colon removed the patient proceeds with radiation therapy.
References
Byers, T., Wender, R. C., Jemal, A., Baskies, A. M., Ward, E. E., & Brawley, O. W. (2016). The American Cancer Society challenge goal to reduce U.S. cancer mortality by 50% between 1990 and 2015: results and reflections. CA: a cancer journal for clinicians, 66(5), 359
Kuldipsinh, T., & Yadav, J. S. (2017). A REVIEW-ORAL COLON SPECIFIC NANOPARTICLES FOR TREATING CANCER. Pharma Science Monitor, 8(2).
Rawla, P., Sunkara, T., & Barsouk, A. (2019). Epidemiology of colorectal cancer: Incidence, mortality, survival, and risk factors. Przegla̜d Gastroenterologiczny, 14(2), 89.
Siegel, R. L., Miller, K. D., Fedewa, S. A., Ahnen, D. J., Meester, R. G., Barzi, A., & Jemal, A. (2017). Colorectal cancer statistics, 2017. CA: a cancer journal for clinicians, 67(3), 177.
Smith, R. A., Andrews, K. S., Brooks, D., Fedewa, S. A., Manassaram‐Baptiste, D., Saslow, D & Wender, R. C. (2018). Cancer screening in the United States, 2018: a review of current American Cancer Society guidelines and current issues in cancer screening. CA: a cancer journal for clinicians, 68(4), 297-316.
Yde, J., Larsen, H. M., Laurberg, S., Krogh, K., & Moeller, H. B. (2018). Chronic diarrhea following surgery for colon cancer—frequency, causes, and treatment options. International journal of colorectal disease, 33(6), 683-694.