Colon cancer is the fifth most common cancer in India after breast, cervix, oral cavity and lung cancer. People who live a sedentary lifestyle, those who are obese and those who smoke a lot of tobacco are more likely to suffer from colon cancer. Diet is an important factor as the colon is a part of the digestive system. After compiling data from twelve cancer registries of India, it was noted that the risk of colon cancer has been rising slowly. It is predicted that by 2035, colon cancer is expected to rise by a staggering 80 percent.
Contributing factors to Colon Cancer
There is no exact cause for colon cancer. Although there are several potential risk factors which increases the chances-
- Polyps-Precancerous polyps that exist in the large intestine causes colon cancer. There are two types of polyps:
- Adenomas- Similar to the normal lining of the colon but looks different under the microscope. They become cancerous easily.
- Hyperplastic polyps- These are generally benign and therefore, colon cancer develops from these types of polyps very rarely.
- Genes- Genetic mutations can lead to a change in the DNA, which can result in uncontrolled cell growth. This can be inherited from family members but most colon cancers occur in people without a family history.
- Diet and habits- A diet that is low in fiber and high in fat, calories, red meat, alcohol, and processed meats puts one at a higher risk of colon cancer.
- Underlying conditions- Conditions such as diabetes, radiation treatment for other cancers, inflammatory bowel diseases, such as ulcerative colitis or Chron’s disease have been associated with an increased risk of cancer.
What is the Staging of Cancer?
In simple words, staging refers to the process of finding out how much cancer is in a person’s body and where it is located. Here is a brief summary of all the stages of colon cancer-
- Stage 0: This is the earliest stage of cancer. Also known as carcinoma in situ, it does not grow further than the inner layer of the colon.
- Stage 1: Grows in the next layer of tissue, but has not reached the lymph nodes or other organs.
- Stage 2: The cancer has reached the outer layers of the colon, but not spread beyond the colon.
- Stage 3: Also grown through outer layers of the colon and has reached one to three lymph nodes.
- Stage 4: Other tissues beyond the wall of the colon are affected and cancer has started to spread to other parts of the body.
‘Survival Paradox’ of Colon Cancer
A recent research study reveals that there is a “survival paradox” linked to colon cancer. According to researchers, patients with higher stage such as stage IIIA have better chances of survival than patients suffering from lower stages such as stage IIB or C. This is considered as a paradox because it deviates to the usual pattern of staging categories.
According to a report published online in Surgery, a team from Louisiana reinvestigated this paradox as “there is no proven factor” that can shed some light on the dilemma.
The Louisiana team reviewed results from the group of 16,471 patients with stage IIB or C and stage IIIA colon cancer over a decade (2003 to 2012) in the National Cancer DataBase. In addition to this study, the investigators found that patients with higher-stage disease have better median survival than those with lower-stage disease.
The 5-year overall survival rate was 84.3% for stage III A with no residual tumor while for stage IIB/C patients it was 73.3%.
The treatment is mainly aimed at to remove cancer and get relief from painful symptoms. It majorly depends on the stage as well as the type of cancer. Other factors to consider are age, health status, and other characteristics of the option.
The treatment for colon cancer mainly includes surgery, chemotherapy and radiation therapy.
Before initiating the surgical procedure, surgeons provide with some drugs or medicines such as Aminosalicylates, Corticosteroids, Immunomodulators, Biologics, etc to cure the mild pain and some gastric symptoms in the abdomen. The patient is then moved to an operating room and positioned on a table. He or she will be given a general anesthesia medication that induces sleep so that the patient is unable to feel any pain during the operation. The surgical team will then proceed with the colectomy. Colon surgery is generally performed in two ways:
Traditional colectomy. Traditional surgery requires a surgeon to make an incision of about 6 to 8 inches long in the abdominal wall to access the colon. The surgeon uses surgical tools to cut free the intestine from the surrounding tissue and cuts a part of the colon or the entire colon.
Laparoscopic colectomy. In laparoscopic colectomy is also called minimally invasive colectomy as this involves several small incisions in the abdomen. After that, the surgeon inflates the abdominal cavity with carbon dioxide gas through a tube, known as a cannula which helps them to navigate the laparoscope easily. They pass a tiny high-resolution camera through one incision and special surgical tools through the other incisions. The surgeon views a video screen in the operating room as the tools are used to cut the colon from the surrounding tissue. The colon is then brought out through another small incision or port in the abdomen. This process allows the surgeon to operate on the colon outside of the body. Once the colon is repaired, the surgeon reinserts the colon through the incision.
Either anastomosis or colostomy is carried out after a colectomy. An anastomosis is to stitch the ends of the colons that are left. If any health portion of the colon is left, surgeons make an opening called a stoma on the outer wall of the belly. The colon is then attached to the outer wall. Stool goes through the stoma into a drainage body that is attached outside the body. The whole method is known as colostomy. A colostomy can either be short-term or permanent.
It is generally used to interfere with the cell division process by damaging proteins or DNA in order to damage and kill cancer cells. These treatments aim any rapidly dividing cells, including healthy ones. During chemotherapy, chemicals are administered in cycles so the body has time to heal between doses. Some of the common sides include hair loss, nausea, fatigue or vomiting.
By focusing high-energy gamma rays on cancer cells, radiation treatment damages and kills cancer cells. This can be used as a standalone treatment to shrink the tumor or cancer cells, or alongside other cancer treatments. The side effects include mild skin changes, nausea, vomiting, diarrhea, fatigue, appetite and weight loss.
In developed countries like the US, colon cancer is prevalent, hence there is more awareness about its detection and prevention. In a country like India where the number of reported cases are low, there is a lack of a mechanism of screening programs.
As the disease mainly occurs with lifestyle instability, cancer can be prevented through regular exercise and healthy eating. This combination will go a long way in curbing the condition in India.
Also Read: Some Facts Related to Colorectal Surgery