Colorectal cancer is considered as the 3rd most prevalent cancer across the globe. Two-thirds of colorectal cancer is found in areas of the colon. This type of cancer is curable when detected and treated early. Colorectal cancer is also medically known as colon cancer or rectal cancer.
Signs and symptoms
Symptoms of colorectal cancer are numerous and could be non-specific. These may include:
- Shortness of breath
- Change in bowel habits
- Narrow stools
- Diarrhea or constipation
- Presence of red or dark blood in stool
- Loss of weight
- Abdominal pain, cramps, or bloating
- Other conditions observed from diseases (such as irritable bowel syndrome (spastic colon), ulcerative colitis, Crohn's disease, diverticulosis, and peptic ulcer disease)
Causes and risk factors
Like in most cancers, the exact causes of colorectal cancer are unclear but there are risk factors that may increase an individual’s chance of developing such a condition. The risk of acquiring colorectal cancer is increased:
- When there is personal or family history of colorectal cancer or non-cancerous (benign) polyps in the colon
- Among individuals with personal or family history of inflammatory bowel disease
- In men and women at the age of 50 and above
- Among females with history of cancers such as breast cancer, ovarian cancer, or uterine cancer
- Among individuals with ulcerative colitis, where the lining of the colon becomes inflamed
- Among those who have a diet high in protein, saturated fats and calories, but low in fiber
- Among alcoholics and smokers
- Among the overweight or those who lead sedentary lifestyles
- When there is presence of polyps in the colon or rectum especially when left untreated
The risk factors mentioned above do not guarantee that a person experiencing one or more risk factors will develop the disease. It just increases a person’s chances of getting the disease.
Diagnosis and tests
Colon cancer is a curable disease when detected early. It is most curable when detected before the development of the symptoms. Screening tests include:
- Colonoscopy (procedure that views the entire colon)
- Fecal occult blood test with flexible sigmoidoscopy (views the lower half of the colon)
- Barium enema
- Virtual colonoscopy or CT colonography
Routine screening is highly recommended are recommended among high risk individuals. An individual can perform an annual fecal occult blood test with flexible sigmoidoscopy every 3 years; or colonoscopy every 5 - 10 years; or virtual CT colonography every 3 to 5 years.
Treatment of colorectal cancer depends on the extent of colorectal cancer. In its early stages, surgery is the main treatment in order to remove the tumour and surrounding tissue. No further treatment will be necessary if the cancer has been successfully removed. In some instances, there is no need for colostomy if the surgeon is able to reconnect the intestines after removing the tumour. However, this may not always be possible. A temporary or permanent colostomy might be required in some cases. Other forms of treatment can be combined with surgery to reduce the chances of the cancer recurring. Chemotherapy may be applied if cancer cells have spread to other parts of the body. In rectal cancer, radiation therapy, can help stop tumour cells from dividing and growing further. This procedure may be beneficial to some patients.
Possible complications arising from Colorectal cancer include:
- Blockage of the colon
- Metastasis (condition when the colon cancer spreads to other parts of the body and organs, such as the liver, the lungs, bones, and the brain)
- Anemia (bleeding of polyps may result to lack of red blood cells and/or hemoglobin
- Recurrence (when colon cancer comes back after it has gone into remission)
- Development of another primary colon cancer
Prevention and control
The mortality rate for colorectal cancer has lowered in the last 15 years. The decrease in number may be attributed to increased awareness and screening by colonoscopy.
Early screening tests (particularly before observing symptoms) can help prevent colorectal cancer. Regular screening tests are recommended for high-risk individuals. Colorectal cancer screening can find precancerous polyps. They can be removed before they become cancerous.
A healthy diet and regular exercise can help prevent different types of cancer in general. There are some evidences suggesting that low-fat and high-fiber diets can help lower risk of colon cancer. A healthy lifestyle can be a key in preventing colorectal cancer. Avoiding high-protein and highly processed diet, carcinogens, smoking, alcohol, stress, and a sedentary lifestyle can help reduce the risk of acquiring such a disease.
Some studies have reported that non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen, naproxen, and celecoxib can decrease risk of colorectal cancer. However, the U.S. Preventive Services Task Force and the American Cancer Society discourage taking aspirin or other anti-inflammatory medicines to prevent colorectal cancer. Taking more than 300 milligrams of aspirin and similar drugs a day may cause gastrointestinal bleeding and heart problems.
Cases in the Philippines
Colorectal cancer is one of the most prevalent cancers in the Philippines. It ranks 6th overall (5th leading cancer among men and 7th among women) following lung cancer, breast cancer, liver cancer, cervical cancer and leukemia in the country. National Colorectal Cancer Awareness Month is celebrated in March. Furthermore, worldwide efforts help people become aware about the risk of colorectal cancer.
According to Ramy Roxas, director of the Cancer Center at The Medical City and chief of the Colorectal Surgery Division of the Philippine General Hospital, the Philippines has a lower rate of colorectal cancer than in the United States (excluding Filipinos in the U.S. who are placed as the same rates in U.S.). Despite the lower rate, the country still has higher incidents of colorectal cancer deaths compared to other countries.
Roxas stresses that colorectal cancer is a very preventable condition. Screening and a multi-modality treatment such as chemotherapy, pre-operative radiotherapy, and high quality surgery, can help improve colorectal cancer outcomes.
There is rapid development in colorectal treatment. Younger patients may tolerate aggressive treatment better. The life span of a Stage 4 patient using the older medication is around six months but, through newer chemotherapy methods, life expectancy may go beyond two years.
- MedicineNet.com – Colon Cancer/Colorectal Cancer (Accessed 31 October 2010.)
- Department of Health – Colon Cancer (Accessed 31 October 2010.)
- philSTAR.com – The lowdown on colorectal cancer (Accessed 31 October 2010.)
- abs-cbnnews.com – Colorectal cancer unveiled (Accessed 31 October 2010.)
- – MedlinePlus – Colon Cancer (Accessed 31 October 2010.)
- Philippine Online Chronicles – Knowing Colorectal Cancer (Accessed 31 October 2010.)