What is Colorectal Cancer?
Colorectal cancer is any type of cancer that begins in the large intestine (colon) or the rectum. The rectum is the passageway attached to the end of the colon and both are located at the lower part of the gastrointestinal tract in the abdomen.
Since they are malignant, colorectal cancer can start in one part (colon or rectum) and spread to the other part (rectum or colon), then it can further spread to other areas of the GI tract and organs surrounding them.
This cancer is also referred to as “colon cancer” or “rectum cancer”, depending on where it starts and spreads out from. Colorectal cancer can be seen as common as it is estimated that 1 in 23 females and 1 in 21 males are affected by this cancer in their lifetime.
Also, research states that it is the third highest cause of cancer deaths in males and second in females. However, if dictated and treated early, the severity of the cancer is reduced and there is a lower risk of death.
Types of Colorectal Cancer
Colorectal cancer has various types and they include:
- Adenocarcinomas, which is the most common type of colorectal cancer. These are cancerous cells that make mucous in the colon or rectum.
- Sarcomas; cancerous cells that form in the soft tissue of the large intestine or muscles
- Carcinoids; cancer cells that form in the hormone making cells of the colon
- Lymphomas; malignant cells that form in the lymph nodes from the colon
- Gastrointestinal stromal tumors; these cancer cells are first benign before they turn cancerous and begin to spread out.
Other very rare types include Turcot Syndrome, Juvenile Polyposis Coli, Peutz-Jeghers Syndrome (PJS).
There are also hereditary colorectal cancers which can be Hereditary Nonpolyposis Colorectal Cancer (HNPCC) or Familial Adenomatous Polyposis (FAP).
Colorectal cancer begins when the cells in the rectum or colon mutate and grow abnormally and uncontrollably. It is not clear what causes the abnormal mutation of the cells, but some factors may contribute to the growth of these cells.
These risk factors may include:
- Family history of colorectal cancer or other cancers.
- Presence of other cancers such as ovary, uterine, cancer, small intestine, etc.
- Polyps in the colon or rectum that may later become cancerous.
- Diseases such as inflammatory bowel disease(IBD), ulcerative colitis, Crohn’s disease, etc.
- High cholesterol and calories levels.
- Smoking and high alcohol consumption.
- Age; people above the age of 50 are more likely to have this cancer.
The stages of colorectal cancer show how far gone the cancer is. By knowing the stage, your doctor can determine which treatment is best for you.
The stages include:
- Stage 0 (also referred to as “carcinoma in situ”)
In this stage, the cancerous cells are still in the inner layer or layer of the large intestine or rectum.
- Stage 1
The cancer cells grow through the lining of mucosa and probably into the muscular layer of the colon or rectum, but may have not shown on the walls of the organs.
- Stage 2
At this stage, cancer penetrated through the muscular layers into the walls of the colon or rectum but has not affected other areas yet.
- Stage 3
Cancer spreads into the nearby lymph nodes but has not affected other body parts.
- Stage 4
Cancer has invaded other parts and organs of the body.
There is a point after effective treatment that colorectal cancer can go into remission. When cancer returns, this is called the “Recurrent Stage”
Signs of colorectal cancer are not evident in the early stages (stage 0 and 1). In stage 2, signs such as abdominal pains may begin to surface but are easily overlooked with symptom relief medications. By stage 3 and 4, which are the late stages, symptoms become very noticeable or severe.
In general, symptoms may include:
- Abdominal cramps and pains
- Bloated abdomen
- Excessive gas in the abdomen
- Chronic fatigue and weakness
- Diarrhea or constipation
- Narrow stools
- Blood in stools or dark stools.
- Rectal bleeding
- Feeling full when you have not eaten.
- Bowels that feel unemptied even after passing out stools.
- Weight loss
- Nausea and vomiting
- Severe headache/migraine
When cancer spreads to other parts of the body, you may experience:
- Osteoporosis; fracture of bones
- Jaundice; yellowish eyes and skin
- Swollen joints, feet, and hands
- Blurred vision
- Difficulty in breathing.
Diagnosis is performed after a physical examination with your doctor. Your doctor may recommend imagery scans, fecal blood or DNA tests, endoscopic tests, biopsy, etc, according to which he thinks is appropriate for the diagnosis.
Colorectal cancer treatments often depend on the stage at which they are and the severity of the condition. They include:
Surgical procedures are used to remove polyps attached to the lining of the colon or rectal wall or used to remove parts of the colon or rectum that have been maximally invaded by cancer.
If cancer has spread to other parts of the body, surgery can remove the polyps that can be reached and the ones left can be handled by other treatments.
This is the use of chemicals or drugs to destroy cancerous cells and shrink the polyps or tumours in the body. It is often used after surgery to destroy the remaining cancerous cells that may not have been reached. Medications include bevacizumab, fluorouracil, irinotecan, ramucirumab, oxaliplatin, capecitabine, etc.
- Radiation Therapy
This involves the use of powerful and high-energy radioactive beams to target and destroy cancer cells and to stop them from growing and multiplying. It can be used before and after surgery.
This is a minimally invasive surgery that destroys cancerous cells by using ethanol, high-frequency radiation, or cryosurgery. These are taken directly to the tumors or polyps through the guide of an ultrasound or CT scan. The tumors are not necessarily removed after the procedure.
To prevent the development of colorectal cancers, you can take into consideration the following:
- Colorectal Cancer Screening
If you have any of the risk factors listed above like family history of correct cancer and other cancers, bowel inflammatory diseases, age of 50 and above, etc, you will need to undergo screening tests for colorectal cancer very often to detect cancer on time.
There are various screening tests. Talk to your doctor about it so he can give you an option suitable for you.
- Maintain A Healthy Diet
Eat more vegetables and fruits and avoid foods with a lot of insoluble fat, cholesterol, and calories.
- Keep A Healthy Lifestyle
Avoid smoking, reduce your intake of alcohol, exercise regularly, and maintain a healthy weight.