Colon cancer is a malignancy marked by the development of tumorous growths in the large intestine, commonly referred to as the colon. In India, colon cancer ranks 8th among the male population and although it can affect people of any age group, the incidence is quite high in elderlies. Often referred to as colorectal cancer, which is an umbrella term for colon and rectal cancer, it starts as tiny non-cancerous polyps which have a tendency to become cancerous over time. These polyps do not induce any major symptoms in the initial stages, which makes them quite hard to detect. It is due to this very reason that doctors highly recommend regular screening, especially to people who fall in the risk category.
Symptoms associated with colon cancer
Some of the major symptoms that indicate the presence of colon cancer include:
- Diarrhoea and constipation alternating
- Recurrent changes in bowel habits and stool consistency
- Blood in the stools
- Persistent urge to defecate, even after passing stools
- Severe abdominal cramps and discomfort
- Weakness and fatiguer
- Abdominal bloating and gas
- Unintentional weight loss
By far, we do not know what exactly causes colon cancer, however, it is believed to be a result of abnormal mutations in the DNA of the cells that line the colon. As a result of these mutations, the cells divide and grow uncontrollably, eventually giving rise to a mass or lump called a tumour. At an advanced stage, the cancerous cells can enter the bloodline and spread to different areas of the body. This is commonly referred to as metastasis.
What are the various risk factors associated with colon cancer?
Here is a list of factors that are known to increase your risks of colon cancer
- Advanced age, with the cancer being more common in people above 50 years of age.
- Inflammatory intestinal diseases – Chronic inflammatory diseases like Crohn’s disease, which affect the colon, also put you at an increased risk of colon cancer
- Inherited syndromes or genetic mutations like Lynch syndrome and familial adenomatous polyposis.
- Family history of the malignancy
- High consumption of red meat or processed meat
- Having diabetes or insulin resistance
- Undergoing radiation therapy for some other abdominal malignancy
Colon cancer is not diagnosed by physical examination or blood investigations. The patient is required to undergo colonoscopy, which is carried out with the help of a special device, known as a colonoscope. This has a camera on one of its ends, which helps to easily examine the colon and the rectum without any incision. Colonoscopy may also be used to collect a sample of tissues for carrying out a biopsy.
Surgery – The aim of the surgery is to extract the tumour along with the diseased tissue. This may involve the removal of a portion of the colon along with some healthy tissue, i.e. colectomy. Depending upon the stage of the cancer and the extent to which it has spread, doctors may also recommend any of the following:
- Polypectomy i.e. extraction of localized polyps
- Endoscopic mucosal resection, i.e. extraction of larger polyps along with some healthy tissue
- Laparoscopic surgery, which offers a minimally invasive approach to extract the polyps
- Colostomy, that involves the creation of a separate passage for passing out waste
- Surgical removal of the lymph node removal
This is carried out using certain drugs that may be given orally or intravenously, so as to target and kill the cancerous cells. Chemotherapy is usually used in combination with other treatments.
Unlike chemotherapy that involves the use of certain drugs, radiation therapy is given using high-intensity x-ray beams, with the aim of bringing down the size of the tumour and destroying cells that were left behind during surgery.
This uses certain drugs to enhance the patient’s immune and help it fight the malignancy.