Laparoscopic Proctosigmoidectomy and Colorectal Cancer
A laparoscopic proctosigmoidectomy is an operation that removes a diseased section of the rectum and sigmoid colon. The surgery is used to treat the following conditions:
- Cancers of the colon and rectum
- Some types of noncancerous growths in the colon and rectum
- Complicated diverticulitis
The term "laparoscopic" refers to a type of surgery called laparoscopy, which allows the surgeon to complete the surgery through very small (5-millimeter to 10-millimeter) "keyhole" incisions in the abdomen. A laparoscope, a small telescope-like instrument, is placed through a small incision near the bellybutton.
There are five main steps to this surgery.
Step 1: Positioning the Laparoscope
Once you are under anesthesia, the surgeon will make a small cut (about half an inch) near the bellybutton. A laparoscope will be inserted into the abdomen through this incision. Images taken by the laparoscope will be projected onto video monitors placed near the operating table.
Once the laparoscope is in place, the surgeon will make five or six more small incisions in the abdomen. Surgical instruments will be placed through these 5-millimeter to 10- millimeter incisions to complete the surgery.
Step 2: Dividing the Sigmoid Colon
The diseased section of sigmoid colon and rectum must be cut away from the healthy bowel. Before this section can be divided from the healthy bowel, it must be freed from its supporting structures.
The bowel is attached to the abdominal wall by a layer of tissue called the "mesentery," which also contains the main blood vessels (arteries) that supply blood to the left side of the colon and rectum. These arteries will be carefully cut and closed. Your surgeon will free the sigmoid colon and part of the rectum from the mesentery, and cut away the diseased tissue. This part of the mesentery will later be removed with the diseased bowel.
Step 3: Preparing to Rejoin the Colon
The remaining end of the descending colon must be rejoined with the remaining end of the rectum. First, a part of the healthy descending colon is detached from the mesentery so that it can be stretched toward the rectum. Likewise, the rectum is freed from its mesentery so it can meet the end of the colon.
To reduce the risk of cancer cells spreading, the surgeon will wash the rectum with a solution.
Step 4: Removing the Diseased Bowel
The incisions used in laparoscopy are very small, so the diseased section of bowel must be removed in a special way. Your surgeon will enlarge one of the incisions and place a bag into the abdominal cavity. The diseased bowel is placed into the bag. The bag is then pulled out of the enlarged incision.
Step 5: Rejoining the Ends of the Colon
Your surgeon will rejoin the colon by using a special stapling device placed into the rectum. This rejoining of the colon and rectum is called an "anastomosis." The stapling device "fires" a ring of staples to connect the two ends. The anastomosis is checked for leaks and the pelvis is rinsed out.
A drain also may be placed in the abdomen to aid recovery after surgery. The drain will be removed a few days afterwards. All the incisions in the abdomen will be stitched or taped closed.