Dr Muralidhar Nambada
MS (General), DNB (Surgical Gastroenterology), FMAS
Consultant Gastrointestinal Surgeon
WHAT IS COLON CANCER?
Colon is the last part of human digestive system which prepares the stool before presenting it to the Rectum (ending of the alimentary tract) to expel it out. Cancer that occurs in this part of the intestine is called colon cancer.
HOW DOES COLON CANCER DEVELOP?
It usually develops from polyps that arise from cells that form the inner lining layer of the colon, which takes a long period of time before they become cancerous.
WHAT ARE THE SYMPTOMS OF COLON CANCER?
These cancers many not produce symptoms till they attain a significant size. The common symptoms of this cancer are
- A change in the bowel habit which can manifest as either constipation or diarrhea or sometimes patients also have diarrhea alternating with constipation
- Anaemia (low Hemoglobin percentage) due to prolonged and slow loss of blood from the large intestine, which may not be visible to the naked eye (also known as OCCULT BLOOD LOSS)
- Passage of visible blood in stool
- These cancers can sometimes fill the entire lumen of the intestine and cause obstruction to the flow of stool causing mechanical obstruction leading to severe abdominal distension which will need an emergency surgery
- They may also have loss of appetite and weight loss
- Feeling of weakness/ malaise/easy fatigability
WHO CAN GET COLON CANCER & WHAT ARE THE RISK FACTORS?
Anyone can develop a cancer in their colon. However, there are certain individuals who are at high risk of developing colon cancer like
- Those with a strong family history of cancer (especially cancer in the colon/pancreas/prostate/pancreas/breast)
- Those with a history of chronic inflammatory conditions of the colon , like Ulcerative colitis
- Those with extensive polyps throughout their large or small intestine or those who have a family member with these polyps
- Those whose consume low fibre in their diet, and people consuming diets with high red meat or highly processed foods may develop colon cancer
- Smoking & consumption of excess alcohol.
- Patients severe Obesity/Metabolic syndrome (these patients are at high risk for developing breast cancer, pancreas cancer in addition to colon and rectal cancer)
HOW TO PREVENT OR REDUCE THE RISK OF COLON CANCER?
- Healthy Life style ( Healthy dietary habits, Regular Physical exercise, Avoid Smoking and reduce alcohol intake)
- Periodic Screening of High Risk individuals. Screening is a process or attempt to identify cancer, before it produce any of the above mentioned symptoms. Various available screening tools include Fecal Occult Blood Test, Sigmoidoscopy or Colonoscopy. In an average risk individual, these tests can be done after an age of 50 years, but in an individual with a strong family history of colon cancer, these screening tests have to be started early.
- Early Consultation with a Surgeon in case of above mentioned symptoms
HOW DO YOU DIAGNOSE COLON CANCER?
Once there is a suspicion of colon cancer, we perform a COLONOSCOPY procedure (it is an endoscopy through the anus to examine the entire large intestine and the last part of small intestine) to see in which part of the colon the tumuor is and also to see if there are multiple tumours.
Once a tumuor is seen, a small Biopsy (removing a small piece of tissue) is done to confirm that it is cancer. After a diagnosis of cancer is confirmed by a pathologist, we usually try to see in which stage the disease is.
Staging is done by means of an Ultrasound Scan of the Abdomen, Chest X Ray and CT Scan of Abdomen and Chest.
WHAT ARE THE TREATMENT OPTIONS FOR COLON CANCER?
Based on the stage, colon cancer has two treatment options, they are Surgery and/or Chemotherapy. Surgery for colon cancer depends on where the cancer is located. The procedure is known as Radical Colectomy and based on the site, they are named as Radical Right Hemicolectomy ( for cancers in the first part of the colon on the right side), Radical Left Hemicolectomy (for left colon cancers). Radical Sigmoid Colectomy (for the sigmoid colon) and we are now performing these procedures laparoscopically (LAPAROSCOPIC COLON & RECTAL SURGERY).
These patients with colon cancer may require CHEMOTHERAPY based stage which we come to know after the final pathology report following surgery.
With the introduction of newer chemotherapy and immunotherapy regimen for colon and rectal cancer, the 5 year survival rates of patient have increased tremendously even for a patient with Stage IV disease
 or rectum. Also known as carcinoma in situ, in this stage abnormal cells are only in the inner lining of the colon or rectum.){kind=link}