What is Colorectal Cancer?
Colorectal cancer is the cancer of colon & rectum.
Colorectal cancer occurs when the cells lining the colon & rectum grow out of control. These cells create tumour, which is known as cancer (metastatic tumour).
What are the symptoms of Colorectal Cancer?
Colorectal cancer generally does not show any symptoms in the early stages.
Common symptoms of colorectal cancer are:
- Constipation or diarrhoea
- Bleeding or cramping in the rectum
- Dark patches of blood in or on the stool
- Discomfort or bloating in the belly
- Fatigue & loss of appetite
- Pelvic pain
Risk factors & causes of Colorectal Cancer
- Age.The chance of getting colorectal cancer increases with age.
- Gender. Men are more likely to develop colorectal cancer.
- Polyps. These growths are present on the inner wall of colon or rectum which are precancerous. Adenoma is a type of polyp which causes colorectal cancer more likely.
- Personal history. If a patient already had colorectal cancer, there is a chance of relapse before age 60.
- Family. Having family history of colorectal cancer.
- Diet. Certain types of diets which contain a lot of fat and cholesterol and little fibre may lead to colorectal cancer.
- Lifestyle. Smoking, alcohol intake & overweight can lead to colorectal cancer.
- Diabetes. People with diabetes are more likely to develop colorectal cancer.
Diagnosis of Colorectal Cancer
- Complete Blood Test (CBC). This test help to measure the different types of cells in the blood.
- Liver Enzymes. This is blood test conducted to check the liver function.
- Tumour Markers. Blood test done to check the presence of tumour markers, substances made by colorectal cancer cells.
- MSI & MMR testing. This test is done to check if the cancer cells show high levels of gene changes, microsatellite instability (MSI) & to check if the cancer cells have changes in any of the mismatch repair (MMR).
- Abdominal Ultrasound
- Endorectal MRI
- PET CT Scan
- Diagnostic colonoscopy. The entire colon and rectum are checked with a colonoscope, a thin, flexible, lighted tube with a small video camera on the end.
- Proctoscopy. In this test the rectum is checked with a proctoscope, a thin, rigid, lighted tube with a small video camera on the end which is inserted through the anus.
- Biopsy. A small piece of tissue, usually a part of the colon is removed and send to the lab to check for colorectal cancer.
Colorectal Cancer Treatment
Following are the common treatment options for colorectal cancers.
Surgery is generally the preferred first line of intervention for colorectal cancer, specially for early stage cancers. The tumor is removed and adjacent lymph nodes could also be removed. The bowel is usually sewen back but sometimes rectum is removed and colostomy bag is used to collect stools.
Chemotherapy is the use of anti-cancer drug that helps to slow or stop the growth of rapidly dividing cells that cause cancer. It prevents the growth of rapidly dividing cells by killing the dividing cells.
Despite its side effects, chemo is still the most widely used cancer treatment option. Unlike radiation and surgery which treats cancer cells at particular locations, chemotherapy drugs can kill cancer cells that have metastated (spread) to different organs in the body (Read more on: Chemotherapy)
Targeted Drug Therapy
Targeted therapy is a type of cancer treatment that uses cancer drugs. However, it is different from traditional chemotherapy, which also uses drugs to kill cancer cells. In Targeted therapy, the cancer’s specific genes, proteins, or the tissue environment that contributes to cancer growth and survival are targeted. Targeted therapy is generally used with chemotherapy and other interventions (Read more on: Targeted Drug Therapy)
Immunotherapy (also called biologic therapy) is a new type of cancer treatment where the body’s immune system is boosted to help the body fight cancer by itself. Immunotherapy uses substances made by the body or in a laboratory to improve or restore immune system function ( Read more on: Immunotherapy)