Colorectal Cancer

What is the
Colon and Rectum?

The colon and rectum together form the large intestine. It is the last part of the digestive system. It begins where the small intestine ends at the right lower corner of the abdomen. It travels upwards towards the liver at the right upper quadrant, then turns and goes across the abdomen to the left upper quadrant. From there, it turns downwards and travels to the left lower part of the abdomen.

It then travels towards the centre of the pelvis and goes straight down and ends at the anus. The rectum forms the last 15cm of the large intestines and lies within the pelvis. It is so named because it is relatively straight.

Colorectal cancer is the most common cancer in Bangladesh, yet one of the most preventable and treatable cancers in the early stages.
We provide risk assessments, screenings and treatments for all patients.

What is Cancer?

Cancer is an abnormal growth of cells that has the ability to invade into surrounding organs as well as spread to distant sites.

How does Colorectal Cancer Form?

Colorectal cancer originates from the inner lining or mucosa of the colon and rectum. The lining of the colon is continuously growing and shedding. As such, the lining or mucosa is undergoing cell replication all the times. With each replication, there is always a chance of a mutation. Although most mutations are recognised as an error by the body and the mutant cell is removed, sometimes these mutant cells escape the body’s defence mechanism and continue to grow. As they grow, more mutation may occur and after a sequence of 4 or 5 mutations in the cell, they may turn cancerous.

Most of the colon cancer follows the adenoma-carcinoma sequence. What this means is that the colon wall first mutates into adenoma (a non-cancerous form) and over time with more mutation, changes into carcinoma (cancer).

The adenoma is usually in the form of a polyp which is a fleshy protuberance from the colon wall. Larger polyps may appear to have a stalk due to the weight of the polyp pulling on the colon lining.

With time, the adenoma type tissue in the polyp will turn cancerous. It then invades back into the polyp and up the stalk (if there is one) and eventually into the wall of the colon.

Once the cancer has invaded into the wall, it can then spread to distant organs either via the blood stream or the lymphatic system.

Understanding the risk factors and preventive care available for colorectal cancer is key.

What Conditions
Require Colon
and Rectum Surgery?

Majority of the colon and rectum surgery done in Bangladesh are for colon and rectal cancer. Less frequently, they are performed for conditions such as diverticular disease, ulcerative colitis, Crohn’s disease, chronic constipation or rectal prolapse.

Colon surgery is almost always performed through the abdomen. In suitable cases of rectal surgery, the surgery is performed through the anus.

Minimally Invasive Colon and Rectum Surgery

Standard Laparoscopic Colorectal Surgery
The colon and rectum are approached using thin and long instruments instead of making a long open cut.

A 1cm cut is made at the umbilicus and the camera is inserted. Three or four other cuts of 5-10mm is made around the abdomen. This allows instruments to be inserted inside and manipulate the intestines to perform the surgery. One of these cuts is then enlarged to allow the resected colon to be removed from the body.

Single Incision Laparoscopic Colorectal Surgery
With better instruments, we have now moved on to single incision laparoscopic port surgery. This means that instead of having 3-5 small incisions around the abdomen, all the instruments are inserted through a special device that is usually located at the umbilicus. The colon is also removed through the same cut.

Robotic Colorectal Surgery
The latest advancement in technology is robotic surgery. Robotic surgery is also a form of minimally invasive surgery. Likewise, it utilises a few small holes that are made in the abdominal wall. However, unlike standard laparoscopic surgery where a few straight instruments are inserted, fine robotic arms are inserted through these small holes to do the surgery.

Robotic surgery gives the surgeon a 3-dimensional view and higher magnification. This allows easier identification of the nerves and reduces the risk of damage. The flexibility of the instruments is also much better compared to the standard laparoscopic instruments.

The difference between robotic and standard laparoscopic instrument is almost like using your hands compared to using a pair of chopsticks. It also allows for easier surgery deep in the pelvis within the confines of the pelvic bones. In certain cases, this improvement might make the difference between preserving the anus and having a permanent stoma.

Advantages of Minimally Invasive Surgery

With a smaller incision, there is usually less pain and allows the patient to be up and about more quickly. This may or may not result in a shorter hospital stay as that depends on the individual patient. However, with minimally invasive surgery, the patient usually has a faster return to normal daily activities after discharge.