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R:
C
N T
INTR
ODUCTION
I
n the era of total mesorectal excision (TME) surgery, preoperative
radiotherapy (RT) reduces local recurrence (LR) and can be administered either as long-course RT (LCRT) with a 5-uorouracil (5-FU)–
based regimen or as short-course RT (SCRT). For patients with a
positive circumferential resection margin (CRM) at TME, tumor
downstaging is highly desirable. In these circumstances, SCRT is not
as eective as LCRT in preventing LR. To reduce radiation-related
toxicity, eld adjustments and new targeted radiation modalities
should be explored.
Radiation therapy was initially introduced as part of the treatment
regimen of rectal cancer to improve local control in conjunction with
surgery for patients with locally advanced disease. During the past
two decades, neoadjuvant (NA) therapy has evolved signicantly,
not only through its application in serial randomized clinical trials
(RCTs) but also as a result of advances in technology that include
introduction of computerized imaging techniques. Currently, the
treatment of patients with rectal cancer centers around a TME along
with NA therapy. Locally advanced rectal cancers are those that are
stage III and some that are stage II with extensive local tumor spread.
Such patients are treated with similar strategies based on National
Comprehensive Cancer Network recommendations (http://www.nc
cn.org/clinical.asp). However, in the era of modern tumor imaging,
rectal magnetic resonance imaging (MRI) in particular facilitates the
precise estimation of involvement of the CRM, which is the most
important factor predicting LR and systemic disease. e Mercury
Trial investigators reported that for patients with a positive CRM on
preoperative MRI, the risks of LR and systemic spread were signicantly higher than for patients with a negative CRM.
Té
Vuong,
e LR rate was 5% in the patients receiving NA SCRT and 12% in
patients undergoing surgery alone (P <.001), demonstrating that
selective postoperative CT-LCRT is not able to provide the same
results as preoperative treatment.
It has been established that NA RT (either SCRT alone or CTLCRT) provides signicantly better local control than does postoperative CT-LCRT, and LR rates are signicantly improved in patients
receiving NA SCRT. In this study, the benets of NA SCRT were
observed at all tumor levels, including upper third tumors, and were
signicant even for patients with specimens obtained within the
mesorectal plane. us far no survival benet has been demonstrated
for patients who received RT and underwent surgery with the TME
technique. In the Dutch TME trial, NA SCRT had no eect on OS or
cancer-specic survival when all randomized patients were included
in the analyses. However, in patients with a negative CRM who underwent surgery, RT signicantly improved cancer-specic survival.
Unfortunately, this benet was oset by an increase in other causes
of death, resulting in an equal OS rate compared with the group that
underwent surgery only. A subgroup analysis demonstrated that for
patients with TNM stage III cancer who had a negative CRM, 10-year
survival was 50% in the NA SCRT group versus 40% in the surgeryalone group (P = .032). In most studies, the LR rate was reduced from
greater than 10% for patients treated with surgery only to 5% for
patients treated with NA RT and surgery.
NA RT, in conjunction with TME, improves local control but does
not improve OS.
R
Aurélie Garant,
and Tamim Niazi
OLE OF CIRCUMFERENTIAL
RESECTION MARGIN
RADIO
urgery remains the cornerstone of rectal cancer treatment for locally
S
advanced (T3/T4) tumors. To further improve local control (LC) in
rectal cancer, NA RT has been added to surgical treatment. e benet of NA SCRT was rst shown by the Swedish Rectal Cancer Group
in the pre-TME era. Aer a median follow-up of 5 years, the LR risk
was 11% in the group that underwent radiation and 27% in the group
that did not undergo radiation, and the overall survival (OS) rates
were 58% and 48%, respectively. In spite of these excellent results,
the role of RT was questioned aer the introduction of TME. In a
Dutch TME study, the benet of SCRT followed by immediate TME
was demonstrated, with a 10-year LR rate of 11% for patients treated
with TME alone versus 5% for patients treated with SCRT followed
by TME. In the MRC-CR07 study, which has a comparable design,
patients with resectable rectal cancer were randomized between NA
SCRT followed immediately by surgery versus surgery alone. e
patients in the group that underwent surgery alone received postoperative chemotherapy (CT)-LCRT when the CRM was involved.
THERAPY TRIALS
I
n the Dutch TME trial, patients with a positive CRM who had not
undergone RT had an LR rate of 23.3%, whereas those who received
RT showed a drop in LR to 15.5% (P = .16). e MRC-CR07 trial
showed an LR of 13.8% in patients receiving NA SCRT with 5 × 5
Gy and an LR of 20.7% in patients receiving postoperative CT-LCRT.
In patients with a positive CRM, NA SCRT is not as eective in
reducing LR.
TIMODALITY TREATMENT
MUL
APPROACHES
Several Northern European RCTs have demonstrated a signicant
reduction in the LR rate aer SCRT. Optimal treatment for the
dierent stages of rectal cancer and prioritization of treatment modalities are controversial. In Northern Europe, SCRT is the standard of
care for most patients with stage II and III rectal cancer, whereas
CT-LCRT is reserved for more advanced cases with a positive CRM.
On the other hand, in America and southern Europe, most patients
are treated with NA LCRT (LCRT, 45 to 50 Gy) in combination
141
142
CanCer of
reCtum: neo
the
adjuvant
therapy
ith CT. Furthermore, because the EORTC-22921 and FFCD-9203
w
studies demonstrated that the addition of CT to preoperative LCRT
enhances local control in locally advanced (T3/T4) tumors, with this
nding recently conrmed by a recent Cochrane review, patients are
now treated with CT-LCRT, followed by TME.
RANDOMIZED TRIALS
COMPARING
NEOADJUVANT SHORTCOURSE RADIOTHERAPY WITH
CHEMOTHERAPY–LONG-COURSE
RADIOTHERAPY
T
wo RCTs compared SCRT to CT-LCRT: a Polish trial, with 312
patients, and an Australian trial, with 326 patients. Both studies had
a similar design, and sample size was calculated to demonstrate a
dierence of 15% in the rate of sphincter preservation and 10% in
LR, respectively. Both trials showed higher rates of early radiation
toxicity in the CT-LCRT arm when compared with the SCRT group;
grade III to IV acute toxicity rates were 18% versus 3% (P = .001)
in the Polish trial and 28% versus 1.9% (P = .001) in the Australian
study. In the Polish trial, the sphincter preservation rate did not
dier between the groups, with 61% in the SCRT group and 58% in
the CT-LCRT (P = .57). In this trial, the LR rate was slightly lower in
the SCRT group than in the CT-LCRT group at 10.6% versus 15.6%
(P = .21), whereas the opposite tendency was seen in the Australian
study at 7.5% versus 4.4% (P = 0.24). In this latter trial, a dierence
was observed in the group of tumors at or below 5 cm from the
anal verge, with 6 of 48 patients in the SCRT arm versus 1 of 31
patients aer CT-LCRT (not statistically signicant). In the Polish
study, severe late toxicity was observed in 10.1% of patients aer
SCRT and in 7.1% of patients aer CT-LCRT compared with 5.8%
of patients aer SCRT and 8.2% of patients aer CT-LCRT (P = .53)
in the Australian trial (Table 29-1).
At present, because no consensus has been reached regarding the
superiority of one radiation schedule over another, standard RT can
be dened as either SCRT or CT-LCRT.
Five contemporary RCTs have been performed to test the oxaliplatin-based CT regimen: STAR-0145, ACCORD 12/0405-Prodige
246, NSABP R-0447, CAO/ARO/AIO-0448, and the PETACC-6
trial, which compared standard NA 5-FU–based CT and LCRT
(CT-RT) with oxaliplatin and 5-FU CT and NA LCRT. Patients
with T3 or T4 rectal cancer were recruited sequentially. All but
the CAO/ARO/AIO-0448 investigators reported higher morbidity
without any improvement in early endpoints such as pathologic
complete response (pCR) rate (Table 29-2). Therefore, it can be
concluded that the 5-FU–based CT regimen remains standard
when LCRT is used.
RADIA
ME provides optimal tumor bed resection together with the peri-
T
rectal nodes within the mesorectal fascia, but it does not address the
pelvic nodes. e Dutch CKVO 95-04 study is unique in that it has an
arm with more than 908 patients who were treated with TME alone.
In this trial, the LR rate was 5% versus 11% aer a median follow-up
of 12 years. Most of the recurrences were located below the S2-S3
interspace in patients with negative nodes and a negative CRM and
were therefore consistent with the Swedish experience reporting on
the level of S1-S2 interspace. e addition of RT reduced mostly the
central recurrence.
In North America, the denition of clinical target volume for the
treatment of rectal cancer has been based on consensus by a panel of
experts to include coverage of the tumor bed, entire mesorectum, and
perirectal, presacral, and internal iliac nodes, which is supported by
the literature on patterns of LR. It is imperative to note that most of
TION TREATMENT VOLUMES
hese data were derived before the implementation of quality imaging
t
such as pelvic MRI and the introduction of TME.
RADIATION-RELATED TOXICITIES
A
lthough the value of RT is now well established, cumulative data on
long-term toxicities associated with external beam RT (EBRT) raise
concerns. In a meta-analysis, Camma etal reported an increased risk
of septic complications in patients who had undergone RT compared
with patients who had not undergone RT: 21% versus 15.2% (P ≤
.001). Moreover, the group that had undergone RT had an increased
risk of overall complications: 21% versus 5.2% (P <.003). Postoperative adverse events were also higher in the RT group: 57.4% versus 42.3% (P <.02). Finally, patients who underwent RT had a 15%
higher risk of death from vascular or infectious causes compared
with patients who had not undergone RT (P = .02). In 2007, Wong
et al performed a Cochrane Database Systematic Review in which
they assessed the eect of preoperative RT versus surgery alone for
patients with rectal cancer and conrmed the benets of preoperative
RT in reducing LC (hazard ratio [HR], 0.71; 95% condence interval
[CI], 0.64-0.78), with borderline signicance with respect to cancerspecic and OS (HR, 0.93; 95% CI, 0.87-1.0). Late toxicities including pelvic fractures, venothrombosis events, intestinal obstruction,
postoperative stula, cardiovascular death, bowel obstruction, anal
sphincter, and sexual dysfunction were all increased.
us, if NA EBRT has been eective in decreasing LR, the number
of patients requiring treatment will need to be weighed against the
substantial morbidity risks and long-term adverse eects related to
EBRT. Reducing treatment volumes to the level of S1/S2 might be the
most eective and simple means of improving the therapeutic index.
THER PERIOPERATIVE RADIATION
O
TREATMENT OPTIONS
Boosting the Dose
ost patients with rectal cancer do well with current management,
M
but less favorable cases with a positive CRM or recurrent tumors aer
previous pelvic RT remain a clinical management challenge. In these
situations, other radiation modalities, apart from EBRT, could be
considered.
e likelihood of achieving tumor downstaging and/or R0
improves as a function of the dose. Wiltshire etal investigated the
value of dose escalation with 5-FU CT in a phase II trial for patients
with operable rectal cancer. e three dose levels were 40 Gy in
20 fractions, 46 Gy in 23 fractions, and 50 Gy in 25 fractions and
included 46, 52, and 36 patients, respectively. e pCR rates were
15%, 23%, and 33% (P = .07), respectively, and the 2-year relapse-free
survival rate was 72%, 90%, and 89%, respectively (P = .02). In the Lyon
RCT study, R96-0256 NA RT alone using 39 Gy in 13 fractions was
compared with the same RT with boost (85 Gy in 3 fractions) using
contact x-ray for 88 patients with low rectal cancer (5 cm or less from
the anal verge). A signicant improvement in pCR rate was seen in
the contact x-ray boost arm (2% vs. 24%), along with a complete or
near complete sterilization of the operative specimen (34% vs. 57%),
resulting in a signicant increase in sphincter-preserving surgery in
the boost group (44% vs. 76%, P = .04). At a median follow-up time of
152 months, although there was no dierence in OS and LC, the rate
of colostomy-free survival was 37% versus 71% (P = .001) in favor of
the boost arm. Using modern preoperative staging imaging, Jakobsen
etal conducted a recent randomized controlled trial on T3/T4 tumors
with dose escalation, comparing CT-LCRT delivering 50.4 Gy in 28
fractions versus a dose escalation to 60 Gy with the same regimen
(50.4 Gy/28 fractions) and high-dose-rate endorectal brachytherapy
(HDREBT) as a boost modality to deliver 10 Gy. A negative CRM rate
RECTAL AND PARARECTAL REGION
143
TABLE 29-1: Five-Year Local Control and Overall Survival Rate Results from Selected Randomized Clinical
Trials Using Preoperative 5-Fluorouracil–Based Chemotherapy and Long-Course/Short-Course Radiotherapy
RCT T/S Status No
erman trial: preop-
G
T1-T4 405 62 6 76 1.9
erative
. of Patients Median Age, yr LR Rate at 5 yr, % OS at 5 yr, % pCR Rate, %
German trial: postop-
T1-T4 394 62 13 74 0 (P < .001)
erative
Dutch trial TME alone S1-S4 908 66 10.9 63.5 0
Dutch trial NA SCRT +
S1-S4 897 65 5.6 64.2 0
TME
MRC-CR07 NA SCRT S1-S4 674 65 4.7 70.3 N/A
MRC-CR07 postopera-
S1-S4 676 65 11.5 67.9 N/A
tive
CT-LCRT
Polish trial SCRT T3-T4 155 60 9 67.2 (4 yr) 0.7
Polish trial CT-LCRT T3-T4 157 59 14.2 66.2 (4 yr) 16.1
(P N/A)
Trans Tasman SCRT T3 162 63 7.5 (3 yr) 74 0
Trans Tasman CT-
LCRT
T3 161 64 4.4 (3 yr) 70 12.4
(P N/A)
FFCD-9203 NA LCRT T3-4 367 63 16.5 67.9 3.6
FFCD-9203 NA CT-
T3-4 375 64 8.1 67.4 11.4 (P < .0001)
LCRT
-LCRT, Chemotherapy–long-course radiation therapy; LR, local recurrence; N/A, not available; NA, neoadjuvant; OS, overall survival; pCR, pathologic
CT
complete response; RCT, randomized controlled trial; S, stage; SCRT, short-course radiation therapy; T, tumor; TME, total mesorectal excision.
ABLE 29-2: Tumor Pathologic Complete Response Rate from Published Randomized Clinical Trials Using
T
eoperative Oxaliplatin and 5-Fluorouracil–Based Chemotherapy and Long-Course Radiotherapy
Pr
RCT T/S Status No
CCORD 12: capecitabine + LCRT T2-T4 293 63 13.9
A
ACCORD 12: capecitabine + oxaliplatin +
T2-T4 291 61 19.2 (P = .09)
. of Patients Median Age, yr pCR rate, %
LCRT
STAR-01: 5-FU + LCRT T1-T4 377 63 16
STAR-01: 5-FU + oxaliplatin + LCRT T1-T4 362 62 16 (P = .904)
NSABP R-04: 5-FU + LCRT SII-SIII 804 N/A 19.1
NSABP R-04: 5-FU + oxaliplatin + LCRT SII-SIII 804 N/A 20.9 (P = .46)
CAO/ARO/AIO-04: 5-FU + LCRT T1-T4 623 63 13
CAO/ARO/AIO-04: 5-FU + oxaliplatin +
T1-T4 613 64 17 (P = .038)
LCRT
PETACC-6: capecitabine + LCRT T3-T4 547 N/A 11.3
PETACC-6: capecitabine + oxaliplatin +
T3-T4 547 N/A 13.3 (P = .31)
LCRT
5-FU, 5-Fl
S, stage; T, tu mor.
uorouracil; LC RT, long-course radiation therapy; N/A, not available; pCR, pathologic complete response; RC T, randomized controlled trial;
144
CanCer of
reCtum: neo
the
adjuvant
therapy
f 90% versus 99%, respectively, was observed (P = .03) for T3 tumors
o
only in favor of the boost arm.
INTRA
OPERATIVE RADIATION
THERAPY
Intraoperative radiation therapy (IORT) has been developed to
further optimize local control, especially in this unfavorable tumor
group (T3 or T4 or N+ and M0). Most studies have investigated IORT
in combination with EBRT. is regimen delivers a higher radiation
dose to the clinical target volume (CTV) at the time of surgical exploration with the advantage of accurate treatment delivery to the area of
maximum concern, with adjacent normal structures displaced from
the irradiation eld. Because it is administered at the time of surgery,
IORT can only be delivered in a single dose, usually varying from 10
to 20 Gy, with the peripheral nerve dened as principal dose-limiting
normal tissue. e benets of IORT as a means of delivering higher
doses and improving LC have been reported, and some data were
quite compelling despite being small retrospectives series as a result
of the limited access to IORT equipment worldwide. e results are
most benecial in patients undergoing complete resection. e IORT
literature includes a large spectrum of tumors because the selection
criteria varied from one center to another, making the evidence of
benets dicult to ascertain. However, Dubois etal reported on a
unique IORT RCT with 142 patients who had T3/T4 primary and/
or recurrent tumors in which EBRT using 40 Gy alone was compared
with the same EBRT with an IORT boost (an additional 18 Gy). No
disease-free survival benets (P = .7808) were identied from the
addition of IORT. In this series, it is possible that the composite population of T3 and T4 tumors contributed to these negative results.
e. At the Jewish General Hospital (McGill University), in the less
dos
favorable T4 tumors for which optimal tumor downstaging is highly
desirable, IMRT was explored as a means of dose escalation with 60
Gy in 25 fractions during neoadjuvant treatment for 60 patients identied by pelvic MRI as having a positive CRM. e R0 rate was 90%
and a multivisceral resection rate was 29.5%. e overall acute toxicity prole was acceptable, with a distribution of a grade 3 or greater
rate of 16.6% for GI, 18% for skin, and 10% for bone marrow.
e role of IMRT requires further demonstration of meaningful
clinical benets in patient outcomes to further substantiate its routine
application in the treatment of rectal cancer.
HIGH-DOSE-RATE ENDORECTAL BRACHYTHERAPY
At the Jewish General Hospital (McGill University), image-guided
HDREBT was developed as a highly targeted RT NA modality for
persons with low T2 with a positive CRM and selected T3 rectal cancer. e treatment consists of 26 Gy in four consecutive fractions prescribed to the deepest aspect of the tumor bed. It is performed in the
ambulatory setting, without CT. Acute proctitis was the only toxicity
observed with 1% grade 3 toxicity. In more than 500 patients treated,
at a median follow-up time of 5 years, the LR rate was 4.5%, which
compared favorably to NA CT-LCRT. In contrast to EBRT, HDREBT
allows lower normal tissue exposure to radiation and is given without
CT, and thus it is less costly and less toxic. An important observation from this institutional experience remains the excellent LC rate
despite the absence of an attempt to treat pelvic nodes and signicantly smaller MRI-based treatment volume when compared with
the standard volume used with EBRT.
INTENSITY
-MODULATED RADIATION
THERAPY
T was initially based on two-dimensional planning with standard
R
treatment elds using anatomic bony landmarks. In the early 1990s,
three-dimensional (3D) imaging radiation planning systems were
introduced that permitted 3D denition of the target and normal
tissues by using a thin-section computed tomography (CT) scan. A
decade later, the new generation of linear accelerators were equipped
with dynamic multileaf collimators (MLCs) capable of following
the projection of the target as the accelerator gantry arcs around the
patient. As a result of MLC delivery and accurate tumor localization
of areas at risk, a safe dose to targets in a variety of areas has led to
an improvement in local tumor control while reducing the radiation
dose to normal structures. is technology has signicantly contributed to the therapeutic index of RT of head and neck cancer. Subsequently, intensity-modulated RT (IMRT) was tested for treatment of
pelvic tumors, in particular anal canal cancer, and was shown to be of
value in reducing skin and gastrointestinal (GI) toxicities. However,
in rectal cancer, few preliminary studies have been performed, and
the benet of IMRT has not been demonstrated. e acute toxicity
data from the multi-institutional radiation therapy oncology group
(RTOG)-0822 study was not signicantly convincing, with 51% of
grade 2 or greater GI toxicity versus 58% (P = .31) in the conventional
3D-based RTOG-0247 study. Major dierences in the CTVs contributed to inconsistent results. In gynecologic and anal canal cancer,
external iliac and inguinal nodes are routinely included, whereas in
rectal cancer, the CTV is posterior. Because radiation is currently
administered in the context of an NA setting, it is unusual that small
bowel loops are close, unlike in the era of adjuvant treatment. Consequently, even with use of the conventional 3D technique, the incidence of grave GI toxicity is unusual, especially if the CTV superior
limit is adjusted to the S1-S2 level.
IMRT has interesting virtues and allows superior dose conforma-
tion within the CTV with the ability to limit normal tissue radiation
SUMMAR
n the era of TME, preoperative RT reduces LR and can be given either
I
Y
as LCRT with a 5-FU–based regimen or as SCRT. For patients with
a positive CRM, tumor downstaging is highly desirable, and SCRT is
not as eective to prevent LR. Contemporary patterns of recurrence
suggest that it is possible to lower the upper limit of the treatment
eld level. In an eort to reduce RT-related toxicity, eld adjustments
along with exploration of new radiation options are desirable.
g g e
u
S
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of a phase I/II study. Dis Colon Rectum. 2002;45:1486–1493. discussion
1493–1495.
Vuong T, Richard C, Niazi T, et al. High dose rate endorectal brachy-
therapy for patients with curable rectal cancer. Semin Colon Rect Surg.
2010;21:115–119.
Wiltshire KL, Ward IG, Swallow C, etal. Preoperative radiation with concur-
rent chemotherapy for resectable rectal cancer: eect of dose escalation on
pathologic complete response, local recurrence-free survival, disease-free
survival, and overall survival. Int J Radiat Oncol Biol Phys. 2006;64:709–
716.
Wong RKS, Tandan V, De Silva S, etal. Pre-operative radiotherapy and cura-
tive surgery for the management of localized rectal carcinoma. Cochrane
Database Syst Rev. 2007;(2). CD002102.
C
R:
O M
Kn
ut Magne Augestad, Benjamin Crawshaw, and Conor P. Delaney
INTR
ODUCTION
T
wo decades ago, surgery for rectal cancer was associated with local
recurrence rates as high as 30% and poor long-term overall survival.
However, during the past 10 years, survival has signicantly improved
and the local recurrence rate has decreased. Several important factors have contributed to this increase in overall survival for patients
with rectal cancer, including new regimens for radiotherapy/chemotherapy, centralization of surgical practice, and multidisciplinary
treatment. However, the most important single factor for increased
survival has been the paradigm shi related to surgical technique.
In the early 1980s, attention was focused on the “holy plane”
between the fascia propria of the rectum and the presacral fascia, and
a dissection technique within this plane was proposed that would
keep the mesorectal fascia intact. is total mesorectal excision dramatically reduced local recurrence rates to 5% to 10% and increased
the overall 5-year survival among patients with rectal cancer to about
71%. is signicant improvement in outcomes has led to widespread
acceptance of total mesorectal excision as the standard technique for
surgical treatment of rectal cancer.
e second technical issue aecting rectal cancer surgery has been
the evolution of minimally invasive surgery. During the past decade,
laparoscopic rectal cancer surgery has been associated with less postoperative pain, shorter hospital length of stay, and lower readmission
rates. Laparoscopic surgery has increasingly been accepted as the
standard approach to rectal cancer resection. Oncologic outcomes
appear to be similar to those of open surgery, although data from
some newer trials are pending.
is chapter outlines the principles of radical surgery for rectal
cancer based on our experience and publications. Transanal excision
is covered in a separate chapter. Important surgical decision-making
choices will be highlighted, and a stepwise approach to the operative
management of rectal cancer will be described.
he IMV, allows well vascularized descending colon to reach the anus
t
for anastomosis. e le ureter lies in the retroperitoneum, behind
the sigmoid mesentery and lateral to the gonadal vessels. It can be
identied posterolaterally as it crosses over the internal iliac artery
and vein, posterior to Toldt’s fascia, to run around the pelvic side wall
on its way to the bladder. e inferior hypogastric plexus lies behind
the IMA at the pelvic brim, receiving the hypogastric nerves and contributing sympathetic bers to the pelvic plexus. e pelvic plexus
is composed of these sympathetic bers and parasympathetic nerves
from L2 and L3. It lies on the pelvic sidewall like a fan, buried below
the endopelvic fascia and safe from harm except anteriorly, where the
terminal bers pass to the seminal vesicles and prostate and penis,
deep to Denonvilliers fascia. e risk of damage to this plexus is low,
unless the endopelvic fascia or Denonvilliers fascia is breached during the pelvic dissection.
e mesorectum is a distinct anatomic unit composed of the
rectum, perirectal fat, blood vessels, nerves, and lymphatic vessels. A layer of broareolar tissue called the mesorectal fascia
surrounds the mesorectum, and dissection along the surface of
mesorectal fascia is the key to successful surgical treatment of rectal
cancer. Staying in the loose areolar tissue between the mesorectal
and endopelvic fascia minimizes blood loss and protects the surrounding neurovascular anatomy. Anteriorly, the posterior vaginal
venous system in females lies close, as do the seminal vesicles and
prostate in men. ese structures can be a source of bleeding during dissection of the low rectum; however, if dissection stays on the
rectal side of Denonvilliers fascia, no bleeding occurs at all. Because
dissection anterior to Denonvilliers fascia increases bleeding and
places the neurovascular bundles at risk, it is only performed for
locally invasive anterior tumors.
PRESURGIC
AL PATIENT PREPARATION
AND EVALUATION
KEY ANA
n intimate working knowledge of the anatomy of the rectum is a
A
prerequisite to safe, eective proctectomy.
e inferior mesenteric artery (IMA) supplies blood to the
descending colon, sigmoid colon, and upper rectum. It arises from
the anterior aspect of the aorta and passes downward at the base of
the sigmoid mesentery to the le iliac fossa. e IMA crosses the pelvic brim and then descends within the mesorectum as the superior
hemorrhoidal artery. e other branches of the IMA are the le colic
artery, which is the most proximal branch, and the sigmoid arteries.
e inferior mesenteric vein (IMV) runs parallel to the IMA but continues cephalad to the origin of the IMA up to and behind the tail of
the pancreas. High ligation of the IMA preserves the collateral arterial arcade to the le colon and, in combination with high ligation of
146
TOMIC POINTS
1. Preoperative cancer staging and planning for neoadjuvant radiotherapy/chemotherapy are performed in a multidisciplinary setting. e methods of staging and preoperative patient examination are described in another chapter; however, we favor staging
with pelvic magnetic resonance imaging (MRI) using a standardized rectal cancer protocol.
2. F
unctional sphincter status and defecation pattern: Preoperative
e
valuation of continence is an important predictor of postoperative
results. Patients should be informed about expected postoperative
changes in defecation and the possibility of soiling, especially with
intersphincteric resection. e history should include assessment
of preoperative fecal continence including nighttime soiling and
incontinence relating to liquids, solids, or gas.
reoperative anesthesia and cardiac and pulmonary assess
3. P
m
ent is performed, including blood typing and complete blood
-
unt. We tend to cross-match only patients with antibodies
co
or those undergoing extended resections, because transfusion
rates are low.
reoperative bowel preparation: We use mechanical bowel prepa
4. P
ra
tion for patients undergoing rectal cancer surgery, especially
when a diversion procedure will be used.
5. r
ombosis prevention: Subcutaneous low-dose molecular hepa
r
in is administered prior to the induction of anesthesia, in con-
junction with use of pneumatic compression devices.
ntibiotics: For patients undergoing colorectal resection, we use
6. A
mbination of oral neomycin and metronidazole, as well as in-
a co
travenous antibiotic prophylaxis against both anaerobes and aerobes, which is not continued aer surgery.
7.
e duration of preoperative fasting should be 2 hours for liquids
a
nd 6 hours for solids. Patients undergo carbohydrate loading
preoperatively.
8. Marking for patients requiring a permanent or temporary ostomy
s performed preoperatively.
i
PREOPERA
S
urgery is planned aer careful review of preoperative imaging.
For most cases, review by a multidisciplinary team is required. Any
tumor extension seen on the preoperative and prechemotherapy/
radiotherapy MRI is an indication for neoadjuvant therapy and may
require surgery outside the total mesorectal excision (TME) plane.
Deciding Betw
TIVE DECISION MAKING
een an Open or Laparoscopic
Approach
A l
aparoscopic approach follows the same oncologic principles as an
open surgical procedure. Patients who have a locally advanced tumor
with unquestionable radiologic signs of neighboring organ invasion
generally undergo an open procedure. An open approach may be
considered for certain other patients with extensive prior abdominal
surgery (such as a previous cystectomy or prostatectomy), particularly for obese patients. However, obesity is very rarely an indication
for open surgery in women. In men with a body mass index greater
than 40, an initial laparoscopy is performed and a nal decision is
made about whether to proceed laparoscopically. It is very challenging to perform laparoscopic procedures for men with a body mass
index greater than 50.
Should a Sta
pled or Hand-Sewn Restorative
Procedure Be Performed?
F
or rectal cancers with an inferior border more than 5 cm from the
anal verge, low anterior resection (LAR) and primary anastomosis
generally can be used. Anastomosis also may be suitable for patients
with lower tumors, depending on the distance between the distal part
of the tumor and the dentate line using the preradiation measurement. If the tumor is within 2 cm of the dentate line, a stapled anastomosis is generally not possible, particularly in obese males who may
have a long anal canal and in whom it is dicult to place a transverse
stapler close to the dentate line. For these lesions, a transanal intersphincteric dissection is performed with a hand-sewn anastomosis.
Abdominoperineal resection of the anus and rectum is indicated
in patients with preexisting or likely postoperative incontinence or
invasion of the anal sphincters or the pelvic oor. When the pelvic
oor is invaded, an extralevator dissection is routinely performed.
Inexperience with low rectal dissection, intersphincteric dissection,
and hand-sewn anastomosis, or with radical perineal dissection, is
an indication for referral of the patient to a surgeon and hospital with
the necessary expertise.
RECTAL AND PARARECTAL REGION
SURGIC
-
Total Mesorectal Excision
TME is performed by sharp dissection within the plane that sepa-
-
rates the visceral from the parietal layers of the perirectal pelvic
fascia, enabling radical removal of the rectum with its surrounding
mesorectum intact. e intent of TME is to remove completely the
mesenteric lymph nodes and any nodules of cancer that are present within the mesorectum but are contained by the fascia propria.
TME is based on embryology and anatomy and the concept that
cancer spread will stay conned within the embryologic mesorectal envelope during most stages of the disease. TME achieves a
radical resection along avascular planes without compromising
bladder or sexual function. If the tumor approaches or breaches
the mesorectal fascia, neoadjuvant chemoradiation is indicated,
and the resection should include the aected neighboring organs
where possible, which may mean taking nerves, ureters, the bladder, the prostate, the uterus or vagina, and, in very rare cases, even
the sacrum or iliac vessels. e goal is complete removal with
negative margins.
AL PRINCIPLES
Ligation of the Inferior Mesenteric Artery
e level of ligation of the IMA has been debated. A recent inter-
national survey showed that 69% of rectal cancer surgeons perform
high ligation of the IMA. Some evidence indicates that a high ligation
of the IMA improves overall survival. We perform a high ligation of
the IMA (proximal to the le colic artery), resulting in a D3 lymph
node dissection. A high ligation of the IMA is important in achieving a tension-free, well-vascularized colorectal or coloanal anastomosis, because when the IMV is ligated close to the tail of the pancreas,
mobility of the descending colon is improved.
Distal Resection Margins
e principal goal in surgical treatment of rectal cancer is to
achieve an R0 resection. It is important that cancer-free margins
be achieved both circumferentially and distally. Perforation of the
tumor or of a rectal segment close to the tumor increases local
recurrence threefold. Special care must be taken when dissecting in
the perianal area during abdominoperineal resection (APR). When
a tumor is located in the upper part of rectum, there is no need to
remove the entire mesorectum, and a partial mesorectal excision
can be performed. A clear 5-cm distal resection margin (of both
rectum and mesorectum) is important when resecting upper and
mid rectal cancers, because lymph node metastases can be found
in the mesentery distal to the cancer. In persons with low rectal
cancers, when the entire mesorectum is removed, a distal resection
margin of 1 cm is adequate.
Choice of Anastomotic Configuration
lorectal or coloanal anastomosis may be performed in several ways.
A co
A coloanal anastomosis can be end to end or side to end, with a 6-cmlong coloanal J pouch or a coloplasty. Creation of a J-pouch above a
coloanal anastomosis will improve functional results for the rst 2 years,
compared with coloplasty or straight anastomosis. is option is performed for patients in whom a J pouch can both reach the pelvis and
can t. Although a side-to-end anastomosis is less well studied, it appears
that the functional results may be equivalent to a J pouch. An end-toend reconstruction is generally performed when the anastomosis is hand
sewn or a pouch or side-to-end anastomosis will not t.
147
148
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gement
Drainage
hether routine drainage of the pelvis reduces the frequency of
W
anastomotic leakage aer LAR is unclear. We do not routinely use
drains.
Div
erting Stoma
A di
verting ileostomy helps reduce the clinical manifestations of
anastomotic leak. Moreover, in two recent meta-analyses, a diverting stoma was shown to reduce the frequency of anastomotic leakage
and the need for a second surgery. We recommend use of a diverting
stoma when the anastomosis is lower than 7 cm from the anal verge,
in very elderly or frail patients who might not tolerate a leak, and in
patients who have undergone preoperative chemoradiation. We perform diversion with a loop ileostomy, which is used as the specimen
extraction site in laparoscopic cases.
KEY STEPS OF SURGIC
AL
PROCEDURES
Lo
w Anterior Resection
C
ases involving LAR are generally performed laparoscopically. e
setup we perform is identical for laparoscopic and open cases.
Positioning and Equipment
e patient is positioned on a beanbag to achieve a steep Trendelenburg position. e patient’s legs are placed in stirrups, and the
perineum should be at or below the break of the table. Straps are
used rarely and only for obese patients whose abdominal pannus
may op to one side or the other during lateral rotation. An orogastric tube and Foley catheter are inserted. For laparoscopic cases,
we prefer using atraumatic 5-mm bowel graspers, which also can
be used as pelvic retractors. Dissection is performed with scissors
cautery, but hook cautery may be required, especially at the right
lower pelvic sidewall to avoid electrical short circuiting. Energybased devices are not usually required because the dissection plane
in the pelvis is avascular, but they are used to divide the primary
vessels, based on data from our randomized trials. We do not use
hand-assist and robotic devices.
Trocar Placement
A 10-mm open cutdown is made for the camera trocar in the umbilicus, and a 12-mm port is placed in the right lower quadrant. For
higher anterior resections, this port is usually placed 2 to 3 cm medial
and superior to anterior superior iliac spine, but when performing a
low pelvic dissection, the right side of the pelvic brim limits access
to the low pelvis, particularly in tall men. For this reason, the right
lower quadrant trocar is moved medially in those patients. When an
ileostomy is planned, the site is used for a trocar except for patients
who have such a high body mass index that the stoma site has been
marked in the right upper quadrant. Further 5-mm trocars are placed
in the right upper and le lower quadrants.
Exposure of the Operating Field
e abdominal cavity is inspected for metastatic or other concomitant disease. e patient is placed in the Trendelenburg position
and tilted to the right. e greater omentum is placed in the upper
abdominal cavity, and the loops of the small intestine are carefully
moved upward to expose the retroperitoneum from the pelvis up
to the ligament of Treitz. In obese patients, a 5-mm grasper may be
required through an additional right upper quadrant trocar to help
keep the small bowel out of the operating eld. A medial-to-lateral
or lateral-to-medial approach is chosen according to the preference
of the surgeon; both approaches should be mastered. Toldt fascia, the
correct dissection plane, is most easily found with the medial-to-lateral approach as described in the next section.
Identification of Inferior Mesenteric Vessels and Left Ureter
e sigmoid colon should be lied toward the anterior abdominal
wall to visualize the contours of the IMA pedicle at the level of the
pelvic inlet. e peritoneum is incised beneath the IMA groove. Care
must be taken to preserve the hypogastric nerve plexus by staying
anterior to the Toldt fascia. e dissection plane should display the
posterior surface of the capsule of the IMA, entering into the pelvis in the avascular presacral space. Carbon dioxide rushes into this
space, clearly demonstrating the planes, which keeps the hypogastric
nerves in a posterior position and the ureter in a posterolateral position, safe from injury. If smooth fascial surfaces are not seen or if the
le ureter cannot be found, the dissection may be too deep in the
retroperitoneum. If any uncertainty exists about plane of dissection, a
lateral-to-medial approach can be performed. Starting slightly distal
to the sacral promontory usually helps identify the correct plane. In
very obese patients (particularly males) and some others, the plane is
not easily seen. Before compromising oncologic planes or potentially
damaging any structures, a lateral approach is performed and the lateral side of the mesentery is followed and dissected until the presacral
space is entered. When using an open approach, a lateral-to-medial
approach is preferred. e remainder of the technique is performed
using 5-mm laparoscopic instruments or an open approach, with no
procedural dierences.
Division of the Vessels and Splenic Flexure Mobilization
e dissection continues on the posterior surface of the “mesorectal
package,” up toward the origin of the IMA. A high ligation—that is,
division above the le colic artery—is performed. e laparoscopic
vascular division may be performed with an endovascular stapler,
with clips, or with a laparoscopic electromechanical device, or if an
open procedure is used, it may be performed with absorbable ties. For
the IMV, the dissection continues proximally, and the peritoneum is
incised along its right side up to the ligament of Treitz. e IMV is
divided at this level to ensure optimal mobilization of the le colon.
With gentle dissection, the le mesocolon can easily be lied o the
retroperitoneum from a medial approach. is dissection continues
laterally until the lateral attachments are reached. Finally, the le colic
artery is divided o the IMA, proximal to its bifurcation, to preserve
collateral ow. e lateral side of the colon is then visualized and the
remaining peritoneal attachment is divided with cautery scissors. e
splenocolic and gastrocolic ligaments are divided with scissors cautery, mobilizing the splenic exure as far medially as needed to avoid
tension on the anastomosis.
Mobilization and Division of the Rectum
A 5-mm grasper is used to elevate the uterus or bladder, optimizing
access to the pelvis. In some cases the uterus can be suspended from
the anterior abdominal wall by a suture passed through it on a Keith
needle.
e initial posterior dissection has already been performed while
mobilizing and dening the IMA. Now the right lateral mesorectal
peritoneum is incised by cautery, exposing the avascular loose connective tissue around the mesorectal fascia, which is then dissected
down to the pelvic oor. e key to this dissection is having adequate
upward traction while drawing the mesorectum away from the pelvic sidewall, which keeps the loose areolar tissue demonstrated, and
it becomes the line of dissection. e mid pelvic dissection on the
ight and le sides can be where the plane is most dicult to see, and
r
reat attention must be directed toward staying in the plane, thereby
g
protecting the “erigent pillars” and surrounding anatomy. A useful
trick can be to start the anterior dissection and then work back, joining this with the posterior dissection. By alternately dissecting posteriorly, laterally, and anteriorly, adequate traction can be maintained
on the least dissected side to display the planes. Dissection continues
down to the upper anal canal, at which stage the mesorectum has
tapered and thinned to almost nothing. It is crucial to avoid coning
into the mesorectum below the level of the tumor, as well as to avoid
going too laterally, thereby damaging the pelvic parasympathetic ganglia close to the anterolateral surface of the mesorectum. e anterior incision is made a few millimeters anterior to the apex of the
pouch of Douglas, allowing the plane between Denonvilliers fascia
and the mesorectum to be displayed easily. Complete hemostasis can
be maintained during the entire dissection, and the entire dissection
is oen performed with only 1 or 2 mL of blood loss.
e exact distal margin of the tumor must be veried before the
distal line of resection can be determined. If there is any doubt, a
rigid proctoscopy should be performed intraoperatively. If the veried correct distal resection site is in the upper or mid rectum, a tunnel is made between the posterior rectal wall and the mesorectum,
using a 5-mm dissector or an atraumatic grasper. For low transection
at the anorectal junction, the stapler can be immediately applied to
the bare bowel. In open cases this maneuver is performed with a PItype stapler, and for laparoscopic cases, it is performed with an Endo
GIA–type device. More than one ring is sometimes required, and it
is important to have a straight and smooth nal distal staple line. To
place the laparoscopic stapler, the rectum may be drawn to the le,
opening the angle to insert the stapler low on the right side. If this
maneuver does not create enough space, pressure can be applied to
the perineum to elevate the anal canal and pelvic oor.
Exteriorization of the Specimen
For upper rectal cancers not requiring a temporary stoma, a 4- to
6-cm le lower quadrant incision is made through the 5-mm port
site. e exteriorization of the specimen should always be performed
through a wound protector to reduce the risk of tumor implantation.
e specimen is removed to a nearby table and examined to conrm
an adequate distal margin and document the completeness of the
mesorectal specimen.
For lower tumors, the specimen is removed through the temporary ileostomy site, extending it into a “keyhole” incision if necessary.
Aer returning the J pouch to the abdomen, any ostomy site extension is closed with absorbable sutures, and the port is reinserted for
anastomosis.
Creation of the Anastomosis
When performing a stapled coloanal or low colorectal anastomosis,
a 6-cm colonic J pouch is favored and made with a single ring of a
linear stapler. is option is possible when the J pouch can t into
the pelvis and when there is enough reach. e open end of the colon
with the anvil tied in place is delivered into the abdominal cavity and
the wound is closed or the wound protector is twisted and clamped
before the abdominal cavity is reinsuated. e colonic mesentery
must be oriented to avoid twisting. e circular stapler is inserted
through the anal opening and carefully maneuvered up to the rectal
remnant resection line. e anastomosis is made under direct vision.
A side-to-end anastomosis is less well studied but appears to be an
equally eective option that is becoming a popular alternative.
Desufflation and Closure of Trocar Incisions
e abdominal cavity should be desuated through open trocars.
e wound made for specimen extraction is closed in two layers.
All trocar incisions larger than 5 mm are closed with fascial sutures.
Placement of pelvic drains is usually not necessary.
RECTAL AND PARARECTAL REGION
149
Abdominoperineal Resection
AP
Rs are usually performed by laparoscopic TME, division of the
sigmoid, creation of an end colostomy, and use of a “cylindrical” perineal resection. We tend to use a high lithotomy position and reserve
the eort of changing to a prone position for patients who have anal
tumors that extend further posteriorly and cannot be seen well in
lithotomy. APR is used for low tumors, when a restorative resection
cannot be performed because of invasion of the anal canal, the anal
sphincters, or the pelvic oor. Care is required when removing these
low tumors because historically there is an increased tendency for
tumor perforation during dissection. In addition, R1 resections are
more common with APR compared with LAR. Keeping the pelvic
dissection wide on the levators is important and is increasingly recognized as helping to lower local recurrence rates.
Closure of the Anal Opening
e rst step of an APR is closure of the anus with a 2-0 nylon suture.
Long thread ends are kept to help with traction during the perianal
dissection. In laparoscopic cases we do not perform this step until we
go down to perform the perineal portion, to enable digital examination during the pelvic dissection. Steps 2 to 6 follow the same surgical
principles as described for LAR:
2. P
ositioning, equipment and trocar placement
3. E
xposure of the operating eld
4. I
dentication of le ureter
5. Identication and division of the IMA
dentication and division of the IMV
6. I
e mesosigmoid and its lateral attachments are mobilized sufciently to give adequate length to the colonic stoma. It is not usually
necessary to take down the splenic exure.
Mobilization of the Rectum
Mobilization of the rectum is similar to the technique described for
LAR. It is important to stop the dissection at the level of the coccygeus posteriorly. e anterior dissection can continue distally as far as
possible, which facilitates the dissection from below.
Proximal Division of the Left Colon
e level of division of the le colon is selected to secure a healthy
and well-functioning stoma. e mesocolon is divided, and then the
colon is divided with a laparoscopic linear stapler. e proximal division is performed before the perineal dissection from below is completed because the pneumoperitoneum disappears at the time the
perineal dissection reaches the abdominal cavity.
Perineal Dissection and Exteriorization
An oval incision is made around the closed anus with diathermy. e dissection plane should be outside the external anal sphincter. If necessary,
the puborectalis muscle or even the coccygeus should be removed with
the specimen to secure a safe resection margin. e most technically
demanding dissection is anterior, which is why the dissection should go
as low as possible during the abdominal dissection. e posterior vaginal
wall in women and the urethra in men must not be injured. However,
when the vagina is invaded by tumor, a posterior vaginectomy must be
performed. Once the perineal dissection is completed circumferentially,
the specimen can be removed through the perineal opening.
Closure of Pelvic Wound and Trocar Incisions and Creation of the Colostomy
e perineal opening is rinsed with warmed saline solution. Pelvic and
perineal hemostasis is secured before the wound is closed in layers.
150
CanCer of
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nlike some surgeons, we do not favor the use of mesh. All trocar inci-
U
sions larger than 5 mm are sutured at the fascial level. e le lower
quadrant trocar incision is excised and a colostomy aperture is created. e colostomy is sutured with absorbable sutures. Vertical rectus
abdominis myocutaneous aps are reserved for cases with a very wide
perineal resection, such as a large or recurrent anal cancer.
VIC EXENTERATION
PEL
Surgical Appr
s dened by the Beyond TME Collaborative (see suggested reading),
A
an exenteration entails a pelvic dissection beyond the fascia propria.
It involves the removal of some or all of the pelvic organs, including
the bladder, prostate, seminal vesicles, urethra, vagina, uterus, part of
the sacrum, and/or the lateral pelvic vasculature.
Assessment Bef
ptimizing the patient’s preoperative function before multivisceral
O
resection is important to minimize perioperative complications. A
preoperative multidisciplinary team assessment is mandatory. Formal cardiopulmonary testing assesses tness and identies areas
for potential improvement. General preoperative surgical principles
include perioperative stoma counseling/marking, discretionary ureteric stenting, the availability of hemostatic agents during pelvic dissection, and intensive postoperative monitoring.
Signs of Ir
S
igns of a nonresectable cancer are debated. e Beyond TME Collaborative recommends that encasement of external or common iliac
vessels are a relative contraindication. Streamlined referral pathways
should exist to allow all patients equal access to centers with high
expertise in pelvic exentration.
oaches
ore Exenteration
resectability
ysterectomy, bilateral salpingo-oophorectomy, and a vaginectomy
h
with or without preservation of the anterior vaginal wall. When
the bladder is involved, a partial cystectomy may be carried out,
although trigone involvement requires a total cystectomy with urinary diversion.
Central Recur
solated central recurrences have the best prognosis of all pelvic
I
recurrences. Abdominoperineal excision can be performed, or a
restorative anterior resection can be performed if the tumor is sufciently high, although planes are oen distorted and dissection is
outside of the conventional TME plane.
der Reconstruction
Blad
e role of bladder reconstruction instead of cystectomy and urinary
diversion is unresolved. An intestinal neobladder may be formed
if urethra and its sphincters are preserved. e risk of stulation is
however high, especially with a concomitant low rectal anastomosis.
Another option is to make a continent catheterizable reservoir in the
upper abdomen. e functional results of these reservoirs are usually
good, with up to a 98% rate of continence.
erineal Reconstruction
P
urgeons who are experienced in the use of free-ap rotations or
S
transfer should perform reconstruction of perineal defects. Commonly used reconstruction techniques include the myocutaneous
oblique or vertical rectus abdominis muscle (VRAM) ap, gracilis
muscle ap, gluteal rotation ap, inferior gluteal artery perforator
ap, free ap, or biologic gra with omentoplasty. ere is no established evidence as to which of these techniques is superior; however,
we generally favor a VRAM, which provides bulky healthy muscle
with overlying skin that nicely lls the pelvis. A heavily irradiated
eld is associated with an increased complication rate.
rence
ectomy
Sacr
R0 a
bdominosacral resection for primary rectal cancer beyond total
mesorectal planes and locally recurrent rectal cancer prolongs survival, has an acceptable postoperative morbidity prole, and is associated with acceptable quality of life. Although involvement of S1 or S2
was earlier considered a contraindication to surgery, with appropriate
surgical expertise, there may be a role for resection in highly selected
patients. A sacrectomy distal to S2 is a major procedure but is manageable with experience and a supportive multidisciplinary team.
elvic Sidewall Disease
P
ecurrent cancer in the pelvic sidewall is associated with reduced rate
A r
of R0 resections, especially when the iliac vessels or ureters are involved.
Strategies that are likely to improve the R0 resection rate include an
anatomical dissection of the lymphoid tissues around the nerves and
vessels, targeted radiation, and en bloc removal of iliac vessels. ereafter a reconstruction must be performed with embolization and/or dissection of internal iliac vessels and necessary bony resections.
Anterior Compar
hen only the vagina is involved, a posterior exenteration is pos-
W
sible. is means surgical resection of the rectum, anus, a total
tment/Urogenital Disease
OUTCOMES:
SURVIVAL AND LOCAL
RECURRENCE
e improved management of patients with primary rectal cancer,
including the adoption of TME and neoadjuvant chemoradiation, has
substantially reduced the proportion of patients in whom local recurrence develops from 31% to 9% and improved the survival rate from
55% to 69%. However, fewer data are available for the application
of laparoscopy for rectal cancer. Several single-institution reports
support the feasibility and equivalent long-term outcomes of laparoscopic LAR, and the Conventional versus Laparoscopic-Assisted
Surgery in Colorectal Cancer (CLASICC) study provides the highest
level of evidence to date. e 5-year local recurrence rate for LAR was
9.4% for laparoscopy and 7.6% for open surgery (P = .740). Overall,
the distant recurrence rate in 111 cases at 5 years was 20.9%. No sig-
21%; open, 20.6%; P = .820). Overall survival was also equivalent
for laparoscopic and open resection of rectal cancer (laparoscopic,
60.3%; open, 52.9%; P = .132). is nding suggests that no dierence exists in overall survival at 5 years between treatment arms for
any stage of rectal cancer. In the ongoing COlorectal cancer Laparoscopic or Open Resection (COLOR II) trial, preliminary data show
that in selected patients with rectal cancer treated by skilled surgeons,
laparoscopic surgery can result in similar complication rates, similar
resection margins, and equivalent completeness of resection when
compared with open surgery. In the laparoscopic group, bowel function returned sooner and hospital stay was shorter.