Surgeries for Colon cancer- Colectomy

Colon is the large intestine. It is the part of the gut before the food reaches rectum. Colon is …cm long. It is divided into 4 parts

1. Right colon (ascending colon)
2. Left colon (descending colon)
3. Transverse colon
4. Sigmoid colon.

The most common cancer of the colon is adenocarcinoma. The standard recommended treatment for a colon cancer that has not spread to other areas/organs is surgical removal.

What does the surgical removal of colon cancer consists of?

Colon cancer surgery consists of removal of the cancerous segment along with at least 5 cm of normal bowel on either side. This is done to ensure that microscopic tumor deposits that are not visible are also removed. Along with this all the lymph nodes that drain the concerned colonic segment also have to be removed. These nodes also may harbor microscopic cancer deposits. Removal of these lymph nodes is necessary to correctly stage the cancer and thus help in further treatment after surgery. These nodes lie along the blood vessels that supply the concerned segment of the colon. The blood vessels supplying the concerned colonic segment have to be divided at their origin to remove all the concerned nodes.

What is CME: complete mesocolic excision?

The colon is surrounded by thin layer that is called mesocolic fascia. This layer covers the colon and its blood vessels that supply the colon. Since the lymph nodes draining the colon are situated along the colon they are also contained in this layer. Complete mesocolic excision of the colon means removal of the colonic cancer along with this fascia. This ensures that microscopic cancer deposits and all the draining nodes are removed. Thus CME ensures oncological sound surgery.

Surgery for cancer of Caecum, ascending colon, hepatic flexure: Right colectomy

Surgical removal of the cancer of right colon is called right hemicolectomy.

Right hemicolectomy entails removal of the ascending colon, hepatic flexure, right half of the transverse colon and last 15cm of small intestine. The blood vessels that need to be divided are – ileocolic vessels, right colic vessels and right branches of middle colic vessels. These vessels have to be ligated at their origin from their parent vessels i.e. Superior mesenteric artery and vein. This has to be done so that all the draining lymph nodes are removed to ensure an oncologically sound surgery.

After the right colon is removed, the gut continuity is established by joining the small intestine to the remaining left half of the transverse colon.

Majority of the right colon cancers can be performed by minimal access surgery i.e. laparoscopic or robotic surgery. The advantages are early recovery, less pain, less blood loss and shorter hospital stay.

We recommend open surgery in colon cancers only when we have high suspicion of disease spread beyond colon. This is to ensure that an optimal cancer surgery is performed.

Cancer of the transverse colon: transverse colectomy /extended right hemicolectomy

Surgical removal of the cancer of transverse colon can be achieved by two types of surgeries

a) Extended right hemicolectomy: this is similar to right hemicolectomy described above but with a complete removal of transverse colon to ensure adequate margin beyond the cancer.
b) Transverse colectomy: This entails removal of the entire transverse colon and both hepatic and splenic flexures. The blood vessels that need to be divided are – middle colic vessels. The same principles of surgery are applied here as well.
Majority of the transverse colon cancers can be performed by minimal access surgery i.e. laparoscopic or robotic surgery. The advantages are early recovery, less pain, less blood loss and shorter hospital stay.

We recommend open surgery in colon cancers only when we have high suspicion of disease spread beyond colon. This is to ensure that an optimal cancer surgery is performed.

Cancer of the left colon / descending colon: Left hemicolectomy

Surgical removal of the cancer of left colon is called left hemicolectomy.

Surgical removal of the cancer of left colon entails removal of the descending/left colon, left half of transverse colon. The blood vessels that are ligated here are the left branch of middle colic vessels, and left colic vessels.

After the removal the gut continuity is established by joining right half of transverse colon to sigmoid colon. This can be done either with the help of staplers or hand sewn anastomosis. For left colon cancers we prefer hand sewn anastomosis.

Majority of the left colon cancers can be performed by minimal access surgery i.e. laparoscopic or robotic surgery. The advantages are early recovery, less pain, less blood loss and shorter hospital stay.

We recommend open surgery in colon cancers only when we have high suspicion of disease spread beyond colon. This is to ensure that an optimal cancer surgery is performed.

Minimal access surgery for colon cancers:

As mentioned earlier most of the colonic cancers can be operated using laparoscopic surgery/robotic surgery. This gives lesser pain to the patient, early recovery of the bowel function, less blood loss, shorter hospital stay.

see the case study on laparoscopic colon surgery: Laparoscopic right colectomy in a patient with heart condition