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Compared to traditional open surgery, laparoscopic surgery for colon cancer results in
short-term benefits such as less pain, shorter length of stay, and faster return of bowel
function while maintaining equivalent oncologic outcomes. For this reason, increasing
numbers of colon cancer patients are undergoing laparoscopic surgery.1-3 Similarly, there
are many potential benefits to performing rectal surgery laparoscopically. Although not
well documented, laparoscopic rectal surgery is under active study and may result in the
usual short-term benefits associated with laparoscopic surgery. In addition, compared to
open surgery, laparoscopy can provide unprecedented, unobstructed views of the rectal
dissection planes even in a patient with narrow pelvis, not only for the surgeon but to the
entire surgical team. Magnified views of the surgical planes allow precise and sharp
dissection. The pneumoperitoneum can also help open the planes for mobilization of the
mesorectum.
Despite these potential advantages, adoption of laparoscopic rectal surgery has been limited
for many reasons. Although there are now several prospective randomized trials
demonstrating safety and benefits associated with laparoscopic colon cancer surgery, the
same benefits have not yet been clearly demonstrated for laparoscopic rectal cancer
surgery.1-3 In addition, concerns about inadequate oncologic rectal dissection, anastomotic
complications, and technical challenges have limited wide adaptation of laparoscopic rectal
surgery.4,5 In efforts to retain the benefits of laparoscopic surgery while not
compromising oncologic rectal dissection, others have advocated performing hybrid procedures
in which colonic portion of the surgery is performed using the "pure" laparoscopic technique
and rectal dissection is performed open through a limited low midline or Pfannestiel (low
transverse) incision.6
Hand-assisted laparoscopic surgery is a technique in which the surgeon places a hand into
the abdomen through an airtight access device while performing laparoscopic surgery. By
placing a hand into the abdomen during laparoscopy, surgeons retain their abilities to
manually retract, expose, and manually dissect, which are lost in pure laparoscopic surgery.
Retention of these abilities can significantly expedite the operation. In fact, several
studies have demonstrated that hand-assisted laparoscopic colon surgery results in
significantly shorter operative time and less conversion to open surgery while maintain
similar short-term outcomes compared to "pure" laparoscopic technique.7-9 In rectal surgery
for cancer, sigmoid colon, left colon, and splenic flexure need to be mobilized in order to
allow tension free anastomosis between the colon and the residual rectum. In laparoscopic
proctectomy, HALS compared to SLS technique may therefore, result in shorter operative time
based on colonic portion of the operation alone.
One of the technical hurdles in performing laparoscopic rectal dissection is exposure and
retraction of the rectum. As one dissects down to the distal rectum, especially in patients
with narrow pelvis, crowding and clashing of instruments can result in poor exposure and
dissection. The only prospective randomized trial comparing results of open vs.
laparoscopic surgery to include rectal cancer is CLASICC trial.3 It reported an increased
circumferentially positive margin of cancer following laparoscopic rectal resection with
twice as many patients in the laparoscopic group (12 %) having an involved margin as in the
open group (6 %). This increased radial margin may be related to difficulty in retraction
and exposure. In HALS, rectal exposure and dissection can be either performed directly
through the incision using the open techniques or laparoscopically with manual assistance.
This may result in equivalent oncologic outcomes as the open surgery but with shorter
operative time compared to SLS technique.
A further challenge in laparoscopic rectal surgery is localization of the tumor, which is
less of an issue in colon cancer where the tumor is easily visible or tattooed
preoperatively. This is not possible for rectal cancer, which can pose a problem in both
dissection and safe division of the rectum. Without tactile sensation it can be difficult
to be sure that the stapler is below the tumor. Hand assisted laparoscopic surgery allows
preservation of tactile sensation and therefore circumvent the above problem. The next step
following mobilization of the rectum is division of the rectum and anastomosis. This poses
a challenge for the laparoscopic surgeon for several reasons. The current laparoscopic
stapling devices angulate to a maximum of 65 o making horizontal division of the rectum
difficult. Morin et al reported a leak rate of 17 % below 12 cm from the anal verge and as
high as 25 % in those who were not diverted following laparoscopic rectal surgery.4 Leroy
et al reported a similar leak rate of 20 % in cancers below 15 cm following laparoscopic
rectal surgery.5 Comparatively higher leak rates after laparoscopic rectal surgery may be
related to limitations in currently available laparoscopic surgical staplers. By performing
distal rectal division through the incision by using the open surgical staplers,
hand-assisted laparoscopic rectal surgery may result in lower anastomotic leakage rate.
We hypothesize that hand-assisted laparoscopy may result in shorter operative time while
retaining the benefits associated with laparoscopic surgery. In this study, we plan to
randomly assign patients diagnosed with rectal cancer to undergo either "standard"
laparoscopic surgery or hand-assisted laparoscopic surgery. We will then compare both
peri-operative and long-term outcomes of patients. If our hypothesis is true, hand assisted
laparoscopic approach to rectal surgery may be preferable to standard laparoscopic surgery.
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