Minimally invasive surgery safe for rectal cancer

People undergoing surgery for rectal cancer fare just as well whether they have conventional or minimally invasive laparoscopic surgery, suggests a new international comparison involving 1,044 patients.

However, when the tumor is in the lower rectum, laparoscopic surgery seems better, according to the results in the New England Journal of Medicine.

Overall survival rates were 86.7 percent when the surgery was done with just a few puncture holes in the body versus 83.6 percent when the abdomen was opened up. Just 5 percent of people in both groups had a cancer recurrence within three years.

"This is the largest trial to date and we can now state with evidence that laparoscopic surgery is safe and associated with long-term cancer outcomes that are at least similar to open surgery," Dr. Jaap Bonjer, the lead author, told Reuters Health.

"With laparoscopic surgery, the short-term outcomes are better. What that means is patients experience less pain after surgery, bowel function returns earlier and the post-operative recovery goes more quickly," said Bonjer of the VU University Medical Center in Amsterdam.

But Dr. Heather Yeo, an assistant professor of surgery at Weill Cornell Medical College and New York-Presbyterian Hospital, urged caution because the test involved highly-skilled surgeons operating on specially-selected patients whose tumors had not spread.

And the new findings do not discuss which group was more likely to retain proper bowel and bladder control, or sexual function, an important element for patients, noted Yeo, who was not involved in the study.

The rectum is the lower part of the colon that connects the large bowel to the anus. The rectum's primary function is to store formed stool in preparation for evacuation. Like the colon, the3 layers of the rectal wall are as follows:

Mucosa: This layer of the rectal wall lines the inner surface. The mucosa is composed of glands that secrete mucus to help the passage of stool.
Muscularis propria: This middle layer of the rectal wall is composed of muscles that help the rectum keep its shape and contract in a coordinated fashion to expel stool.
Mesorectum: This fatty tissue surrounds the rectum.

In addition to these 3 layers, another important component of the rectumis the surrounding lymph nodes (also called regional lymph nodes). Lymph nodes are part of the immune system and assist in conducting surveillance for harmful materials (including viruses and bacteria) that may be threatening the body. Lymph nodes surround every organ in the body, including the rectum.

Of the 150,000 cases of colorectal cancer diagnosed each year in the United States, more than 40,000 people are diagnosed with rectal cancer. The most common type of rectal cancer is adenocarcinoma, which is a cancer arising from the mucosa. Cancer cells can also spread from the rectum to the lymph nodes on their way to other parts of the body.