2012 EDUCATIONAL BOOK - American Society of Clinical Oncology

Minimally Invasive Surgery of Rectal Cancer:
Current Evidence and Options
By Atthaphorn Trakarnsanga, MD, and Martin R. Weiser, MD
Overview: Minimally invasive surgery (MIS) of colorectal
cancer has become more popular in the past two decades.
Laparoscopic colectomy has been accepted as an alternative
standard approach in colon cancer, with comparable oncologic
outcomes and several better short-term outcomes com-
MIS HAS become the standard procedure in some
operations, such as cholecystectomy and appendectomy.
Several short-term benefits are associated with MIS,
including reduced postoperative pain and decreased need for
analgesic drugs, more cosmetically pleasing incisions,
shorter length of hospital stay, and earlier return to functionality.
These are the major reasons for the increasing
popularity of the minimally invasive surgical approach.
Jacobs and colleagues 1 first reported a case series of
successful laparoscopic colectomies in 1990. In the beginning,
its application was limited to treatment of benign
lesions. However, the use of MIS in colon cancer raised
concerns about the possibility of port site metastases and
inadequate oncologic resection. Early reports indicated that
the incidence of port site metastasis was approximately 4%
in the laparoscopic group compared with 1% in the open
group. 2,3 This contentious question was resolved by a large
meta-analysis of several controlled studies, which concluded
that the incidence of port site metastasis was 0.87% in the
laparoscopic group compared with 0.34% in the open group
(p � 0.16). 4 Correspondingly, concerns regarding oncologic
outcome were dispelled by several well-designed large, randomized,
controlled studies that demonstrated the equivalence
of laparoscopic colectomy to the conventional open
approach in terms of recurrence and survival. 5-8 Undoubtedly,
laparoscopic colectomy is now considered an alternative
standard approach in the treatment of colon cancer.
Obviously, surgery of the rectum is more challenging for
several reasons, mostly because dissection of the mesorectal
plane is limited by the confines of the bony pelvis and the
goal of preserving the autonomic nerves. Moreover, neoadjuvant
treatment sequelae, especially those secondary to
radiotherapy, may affect the surgical field. Thus, the role of
MIS for rectal cancer is still controversial and substantial
evidence is lacking. We summarize the current status of MIS
in rectal cancer, the findings of contemporary published
studies, and the appropriate application of various existing
techniques.
Laparoscopic Rectal Cancer Surgery:
Where Are We Now?
At present, the American Society of Colon and Rectal
Surgeons (ASCRS) has not endorsed laparoscopic proctectomy
for rectal cancer because of concerns about achieving
adequate mesorectal excision and clear surgical margins
using this technique. 9 ASCRS has encouraged well-designed
trials to examine the safety, efficacy, and benefits of MIS in
rectal cancer surgery, especially in regard to long-term
oncologic outcomes. A majority of these prospective randomized,
controlled trials are ongoing, and the results have not
yet been defined. Thus, MIS for rectal cancer has not become
214
pared to open surgery. Unlike the treatment for colon cancer,
however, the minimally invasive approach in rectal cancer
has not been established. In this article, we summarize the
current status of MIS for rectal cancer and explore the various
technical options.
standard treatment in the United States. 10 Based on evidence
presented in European trials, however, several countries
in Europe and Asia have endorsed MIS as an
alternative to standard open surgery in rectal cancer.
United Kingdom MRC CLASICC Trial
The United Kingdom Medical Research Council Trial of
Conventional vs. Laparoscopic-Assisted Surgery in Colorectal
Cancer (United Kingdom MRC CLASICC) was a prospective
randomized trial that included both patients with colon
cancer and patients with rectal cancer. 7 Of the 794 enrolled
patients, 381 had rectal cancer and the conversion rate was
34%. Within the actual treatment group, 87 patients underwent
open total mesorectal excision (TME) and 189 had
laparoscopic-assisted TME. The primary endpoints were
rate of positive-circumferential and longitudinally resected
margins. No significant difference in either margin of resection
was identified when comparing the two procedures.
Among patients undergoing anterior resection, the rate of
positive circumferential resection (CRM) was slightly higher
in the laparoscopic than in the open group (12% vs. 6%; p �
0.80). In-hospital mortality rates between laparoscopic and
open surgery were not significantly different (4% vs. 5%; p �
0.57), but the mortality rate was higher in patients who
were converted to open surgery.
Regarding long-term outcomes, 5-year results of the
United Kingdom MRC CLASICC have already been published.
11 There was no significant difference in 5-year overall
survival (OS) between the laparoscopic and open groups
(60.3% vs. 52.9%; p � 0.132). Five-year disease-free survival
did not differ either (53.2% vs. 52.1%, respectively; p �
0.953). In converted patients, the overall survival rate was
significantly worse, compared to the other patients who
initially received randomized treatment (p � 0.05). There
was no difference in rate of local recurrence between patients
who had laparoscopic compared with open anterior
resection, although as previously noted, the rate of positive
CRM was slightly higher in the laparoscopic group (9.4% vs.
7.6%; p � 0.74). No data was shown on local recurrence in
patients who had abdominoperineal resection.
From the Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University,
Bangkok, Thailand; Department of Surgery, Memorial Sloan-Kettering Cancer Center,
New York, NY.
Authors’ disclosures of potential conflicts of interest are found at the end of this article.
Address reprint requests to Martin R. Weiser, MD, Department of Surgery, Memorial
Sloan-Kettering Cancer Center, 1275 York Ave., Room C-1075, New York, NY, 10065; email:
weiser1@mskcc.org.
© 2012 by American Society of Clinical Oncology.
1092-9118/10/1-10