Colorectal cancer, also known as bowel cancer, colon cancer or rectal cancer, is any cancer (a growth, lump, tumor) of the colon and the rectum. The World Health Organization and CDC say it is the second most common cancer worldwide, after lung cancer.
A colorectal cancer may be benign or malignant. Benign means the tumor will not spread, while a malignant tumor consists of cells that can spread to other parts of the body and damage them.
Symptoms of colorectal cancer
- Going to the toilet more often.
- A feeling that the bowel does not empty properly after a bowel movement.
- Blood in feces (stools).
- Pains in the abdomen.
- Bloating in the abdomen.
- A feeling of fullness in the abdomen (maybe even after not eating for a while).
- Fatigue (tiredness).
- Inexplicable weight loss.
- A lump in the tummy or a lump in the back passage felt by your doctor.
- Unexplained iron deficiency in men, or in women after the menopause.
Causes of colorectal cancer
Experts say we are not completely sure why colorectal cancer develops in some people and not in others. However, several risk factors have been identified over the years – a risk factor is something which may increase a person’s chances of developing a disease or condition.
The possible risk factors for colorectal factors are:
- Being elderly – the older you are the higher the risk is.
- A diet that is very high in animal protein.
- A diet that is very high in saturated fats.
- A diet that is very low in dietary fiber.
- A diet that is very high in calories.
- A diet that is very high in alcohol consumption.
- Women who have had breast, ovary and uterus cancers.
- A family history of colorectal cancer.
- Patients with ulcerative colitis.
- Being overweight/obese.
- Smoking. This study found that smoking is significantly associated with an increased risk for colorectal cancer and death.
- Being physically inactive.
- Presence of polyps in the colon/rectum. Untreated polyps may eventually become cancerous.
- Having Crohn’s disease or Irritable Bowel Disease have a higher risk of developing colorectal cancer.
- Most colon cancers develop within polyps (adenoma). These are often found inside the bowel wall.
Treatments for colorectal cancer
The patient’s treatment will depend on several factors, including its size and location, the stage of the cancer, whether or not it is recurrent, and the current overall state of health of the patient. A good specialist will explain all the treatment options available to the patient. This is an opportunity for the patient to ask questions and get advice on lifestyle changes that will help recovery.
Treatment options include chemotherapy, radiotherapy, and surgery:
Surgery for colorectal cancer
This is the most common colorectal cancer treatment. The affected malignant tumors and any lymph nodes that are nearby will be removed. Surgeons remove lymph nodes because they are the first place cancers tend to spread to.
The bowel is usually sewn back together. On some occasions the rectum may need to be taken out completely – a colostomy bag is then attached for drainage. The colostomy bag collects stools and is generally placed temporarily – sometimes it may be a permanent measure if it is not possible to join up the ends of the bowel.
If the cancer is diagnosed early enough, surgery may be the only treatment necessary to cure the patient of colorectal cancer. Even if surgery does not cure the patient, it will ease the symptoms.
Chemotherapy involves using a medicine (chemical) to destroy the cancerous cells. It is commonly used for colon cancer treatment. It may be used before surgery in an attempt to shrink the tumor. A study found that patients with advanced colon cancer who receive chemotherapy and who have a family history of colorectal cancer have a significantly lower likelihood of cancer recurrence and death.
Radiotherapy uses high energy radiation beams to destroy the cancer cells, and also to prevent them from multiplying. This treatment is more commonly used for rectal cancer treatment. It may be used before surgery in an attempt to shrink the tumor.
Doctors may order both radiotherapy and chemotherapy after surgery as they can help lower the chances of recurrence.