Rectal Resection

Surgery is usually the main treatment for rectal cancer. The type of surgery used depends on the stage (extent) of the cancer, where it is, and the goal of the surgery.  Either radiation or chemotherapy may be used  before or after surgery.[1]

The type of surgery depends upon the location of the cancer, and how the cancer has developed.  Before doing surgery, the doctor will need to know how close the tumor is to the anus. This will help decide what type of surgery is done. It can also impact outcomes if the cancer has spread to the ring-like muscles around the anus (anal sphincter) that keep stool from coming out until they relax during a bowel movement.[1]

Figure 1. Open vs. Robotic Port Placement

Surgery often involves a bowel resection, although smaller tumors may also be removed using a local excision.

Low anterior resection is the common procedure in which robotic assisted surgery is used. In this procedure the surgeon makes several small incisions (cuts) in the abdomen. The cancer and a margin (edge or rim) of normal tissue around the cancer is removed, along with nearby lymph nodes and other tissues around the rectum.

The colon is then reattached to the remaining rectum so that a permanent colostomy is not needed. (A colostomy is needed when, instead of reconnecting the colon and rectum, the top end of the colon is attached to an opening made in the skin of the abdomen. Stool then comes out this opening.)

Learn more about what robotic assisted surgery is and how surgeons use the technology here.

KHSC becomes Canadian leader in robotic rectal cancer surgery
Kingston Health Sciences Center, Nov 2021

Small cuts, Big Results
University Health Network, Nov 2021

Back in the Field
London Health Sciences Center, Summer 2016

Potential Benefits​

Potential benefits may include:

  • Patients may stay in the hospital for a shorter amount of time than patients who had open[3-5] and the same amount of time, or possibly less, than patients who had laparoscopic[6-13] surgery.
  • Patients may have a similar rate of complications compared to patients who had open surgery[4],[5] and lower, though sometimes similar, rates of complications compared to patients who had laparoscopic surgery.[12],[13][15-17]
  • Compared to patients who had open[3],[5] and laparoscopic[9] surgery, patients who had surgery with da Vinci had similar rates of positive cancer margins (cancer found at the edge of removed tissue).
  • Patients may be less likely to switch to open surgery when performing surgery with da Vinci, compared to laparoscopic surgery.[6-10],[12],[13]

Additional Patient Resources

Visit the the Canadian Cancer Society website for more informational about the disease, diagnosis, treatment options and support available.

Community Groups

Educational Videos

First robotic surgery at London Health Sciences

Robotic surgery and minimally invasive surgical methods

Risks & Considerations

Not everyone is a candidate for robotic assisted procedures, and other treatment options may be available and appropriate. Only a doctor can determine whether robotic assisted surgery is appropriate for a patient’s situation. Surgery of any form contains risks and it is important to discuss risks with your provider. Patients and doctors should review all available information on both non-surgical and surgical options in order to make an informed decision.

Patients have also developed support areas where they are able to speak with each other about the surgery, their experiences, and any issues that they have faced during their treatment. To learn more check out the additional resources above or visit the community section of this website.



[3] Midura, E. F., et al. (2015). “The effect of surgical approach on short-term oncologic outcomes in rectal cancer surgery.” Surgery 158(2): 453-459.

[4] Liao, G., et al. (2016). “Robotic-assisted surgery versus open surgery in the treatment of rectal cancer: the current evidence.” Sci Rep 6: 26981.

[5] Somashekhar, S. P., et al. (2015). “Prospective Randomized Study Comparing Robotic-Assisted Surgery with Traditional Laparotomy for Rectal Cancer-Indian Study.” Indian J Surg 77(Suppl 3): 788-794. 

[6] Lee, S. H., et al. (2015). “Robotic versus conventional laparoscopic surgery for rectal cancer: systematic review and meta-analysis.” Ann Surg Treat Res 89(4): 190-201.

[7] Lin, S., et al. (2011). “Meta-analysis of robotic and laparoscopic surgery for treatment of rectal cancer.” World Journal of Gastroenterology 17(47): 5214-5220.

[8] Memon, S., et al. (2012). “Robotic versus laparoscopic proctectomy for rectal cancer: a metaanalysis.” Ann Surg Oncol 19(7): 2095-2101.

[9] Sun, Y., et al. (2016). “Robotic versus laparoscopic low anterior resection for rectal cancer: a meta-analysis.” World J Surg Oncol 14(1): 61.

[10] Sun, Z., et al. (2015). “Minimally Invasive Versus Open Low Anterior Resection: Equivalent Survival in a National Analysis of 14,033 Patients With Rectal Cancer.” Ann Surg. 263(6):1152-8.

[11] Trastulli, S., et al. (2012). “Robotic resection compared with laparoscopic rectal resection for cancer: Systematic review and meta-analysis of short-term outcome.”Colorectal Disease 14(4): e134-e156.

[12] Xiong, B., et al. (2014). “Robotic versus laparoscopic total mesorectal excision for rectal cancer: a meta-analysis.” J Surg Res 188(2): 404-414.

[13] Yang, Y., et al. (2012). “Robot-assisted versus conventional laparoscopic surgery for colorectal disease, focusing on rectal cancer: a meta-analysis.” Ann Surg Oncol 19(12): 3727-3736.