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25 Colon Cancer Surgical Treatment: Principles ofColectomy
Fig. 25.5 Extended left
hemicolectomy
457
Splenic Flexure andDescending Colon Cancer
Tumors of the splenic exure and proximal descending colon
are usually treated by a left colectomy. This procedure
involves high ligation of the left colic artery and left branch
of the middle colic artery (Fig.25.6). The resultant mesenteric resection includes the areas drained by the distal half of
the transverse colon and the descending colon. The resulting
anastomosis is typically transverse colon to sigmoid colon.
The root of the IMA and superior hemorrhoidal artery is preserved to maintain arterial ow to the remaining sigmoid
colon. If colorectal anastomosis is performed, then the root
of the IMA can be divided.
Technical Aspects
The patient should be positioned in split leg or low lithotomy
position to facilitate stapled end-to-end anastomosis and/or
leak testing of the anastomosis endoscopically. The small
bowel should be positioned on the patient’s right side so that
exposure is gained to the base of the mesentery. Either before
or after mobilization of the colon to its embryologic midline
position, attention is directed to the mesentery. The inferior
mesenteric vein is divided adjacent to the ligament of Treitz.
A decision is made as to whether the sigmoid will be preserved, and then the IMA is divided at the aorta (sigmoid to
be removed), or the left colic artery is ligated at its origin
while preserving the root of the IMA and superior hemorrhoidal artery (sigmoid to be preserved). During these resections, the splenic exure is completely mobilized, and the
left side of the omentum is typically taken with the specimen. The proximal and distal colon transection lines are
determined by the resected blood supply and the margin on
the tumor. For some proximal splenic exure lesions, an
extended left colectomy with division of the main middle
colic artery trunk divided is indicated.
For tumors located in the distal descending colon, a
more formal left colectomy includes resection of the sigmoid colon and a colorectal anastomosis (Fig.25.7). The
IMA is isolated at its origin, making sure to identify and
preserve the left ureter. The IMA is then ligated at its origin, and the inferior mesenteric vein (IMV) is taken near
the ligament of Treitz at the inferior border of the pancreas.
The mesentery is lifted off of the retroperitoneum, and the
entire left colon from the distal transverse colon to the top
of the rectum is removed. It is important to note that
attempts at anastomosis can be difcult due to reach and
tension. To facilitate reach, the IMV should be ligated
proximally. The transverse colon should be mobilized and
omentum released from the stomach. A retroileal anastomosis may be needed to allow reach of the colon to the
rectum for anastomosis in select patients.
458
Fig. 25.6 Segmental left
hemicolectomy for splenic
exure tumor
E. H. Carchman and M. F. Kalady
Fig. 25.7 Formal left
hemicolectomy for
descending colon tumor
Sigmoid Colon Cancer
Sigmoid colon cancer is treated with either a sigmoid
colectomy or a left colectomy, depending on the location of the tumor in the sigmoid colon. More proximal
lesions are best served with left colectomy (as outlined
above) to ensure adequate lymph node harvest. Tumors
in the mid to distal sigmoid colon are adequately treated
with anterior resection of the rectosigmoid/sigmoid
colectomy. There has not been a proven oncologic benefit for formal left colectomy for distal sigmoid colon
tumors.
25 Colon Cancer Surgical Treatment: Principles ofColectomy
459
Technical Aspects
An anterior resection is performed for tumors of the mid and
distal sigmoid colon. The patient is placed in low lithotomy
position. For a medial to lateral approach, the peritoneum is
incised along the root of the sigmoid mesocolon, from IMA
origin to just distal to the sacral promontory. Dissection just
deep to the arc of the superior hemorrhoidal vessels allows
for identication and preservation of the hypogastric nerves,
left ureter, and gonadal vessels. At this point, a decision is
made as to whether to divide the IMA at the aorta or preserve
the left colic artery and instead divide the superior hemorrhoidal artery at its origin (Fig. 25.8). As discussed previously, several studies have demonstrated that there is no
survival advantage of “high” ligation of the IMA although
lack of precise anatomic denitions makes it difcult to draw
denitive conclusions (8, 40, 41). During mobilization of the
sigmoid colon and the ligation of the vessels, the left ureter
should be identied and preserved. Most injuries of the ureter occur at the level of the iliac artery. One then completes
the dissection of the sigmoid and descending colon and its
mesentery off of the retroperitoneum. The distal aspect of
resection is the upper rectum, and the proximal aspect of
resection is typically the junction of the descending and sig-
moid colon, assuring appropriate margins and pulsatile arterial ow to the proximal colon conduit. One then determines
if the descending colon will reach without tension to the rectal stump. If there is any tension, additional maneuvers to
create length for the colon conduit include high ligation of
the inferior mesenteric vein at the inferior border of the pancreas and complete splenic exure mobilization. Some surgeons will routinely mobilize the splenic exure, while some
do so selectively. The anastomosis is then created, typically
in an end-to-end fashion with an endoscopic stapler. As per
routine, endoscopic inspection and pneumatic anastomotic
leak testing, preferably with carbon dioxide as the instilled
gas, should be performed.
Special Circumstances
Obstructing or Perforated Colon Cancer:
Principles ofSurgical Resection
About 15% of patients with colon cancer will present with
acute obstruction or perforation. Management varies based
on location of the tumor and the clinical presentation.
Fig. 25.8 Sigmoid
colectomy
460
E. H. Carchman and M. F. Kalady
Patients who present with acute obstruction due to suspected
colon malignancy typically undergo CT of the abdomen and
pelvis ordered by the emergency room physician. Unless the
patient has undergone recent colonoscopy, urgent watersoluble contrast enema should be considered as the next step
in evaluation. Water-soluble contrast enema will typically
conrm the diagnosis, evaluate for synchronous distal
lesions, and prep the distal colon for possible intraoperative
colonoscopy. For obstructing right colon tumors, right colectomy should be considered. The dilated colon proximal to
the obstruction is removed during right colectomy, and if the
ileocecal valve is competent, the ileum is usually of reasonable caliber, and the patient can thus be considered for primary anastomosis if doing well otherwise. If the ileum is
dilated and edematous, resection with end ileostomy and
mucus stula using a corner of the transverse staple line in
the ileostomy opening as a vent can be considered. Other
options include leaving the closed distal colon segment in
the abdomen (only if one can ensure that there are no synchronous large distal colon lesions), creation of formal colon
mucus stula in the contralateral abdomen, and creation of
ileocolic anastomosis with proximal diverting ileostomy.
If the site of the obstruction is located more distally in the
colon, more extensive resections are necessary. If there is
evidence of proximal colon ischemia, then subtotal colectomy should be strongly considered (Fig.25.9). The decision
as to whether to perform anastomosis (ileosigmoid or ileorectal) should again be based on the condition of the bowel
and the acute and chronic condition of the patient. If the
proximal colon is dilated but not ischemic, then endoluminal
stent as a bridge to formal resection can be considered. If this
is not the favored approach or not possible, then Hartmann
resection with proximal colostomy should be considered.
Only in very rare cases should primary anastomosis, with or
without proximal fecal diversion, be considered due to the
risk of anastomotic leak. If primary anastomosis and proximal fecal diversion is performed, then intraoperative colonic
lavage should be considered in order to clear the diverted
segment of stool, which could otherwise slowly extrude out
of a leaking anastomosis should this complication occur.
In cases of perforation, similar principles as discussed
above are followed. One additional consideration for perforated tumors, however, is the high rate of recurrence and the
need for adjuvant chemotherapy. In this situation, one should
avoid creating a high-risk anastomosis that may leak and
then delay or obviate adjuvant chemotherapy.
Surgical Resection forColon Cancer
intheSetting ofLynch Syndrome
Approximately 3% of all colorectal cancers develop within
the setting of Lynch syndrome. These patients have an
increased risk of developing metachronous colon cancers
due to their genetic predisposition (42). When a curable
colon cancer is diagnosed in the setting of Lynch syndrome,
the American Society of Colon and Rectal Surgeons recommends total abdominal or subtotal colectomy as opposed to a
Fig. 25.9 Subtotal colectomy
25 Colon Cancer Surgical Treatment: Principles ofColectomy
461
segmental colectomy due to the reduced risk of metachronous cancer afforded by extended resection (43). This subject is covered in more detail in another chapter.
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Rectal Cancer: Neoadjuvant Therapy
StevenR.Hunt andMatthewG.Mutch
26
Key Concepts
• Standardized surgery using the total mesorectal excision
concept remains paramount for achieving local control
for rectal cancer.
• Addition of neoadjuvant therapy (short-course radiation,
long-course chemoradiation) along with standardized surgery improves local control.
• Neoadjuvant short-course radiation therapy and longcourse chemoradiation therapy have not improved DFS or
OS for patients with LARC.
• Increased time interval between the completion of radiation therapy and surgery directly impacts the pathologic
response of the primary tumor.
• The administration of systemic multidrug chemotherapy
in the neoadjuvant setting as either induction or consolidation relative to radiation therapy has led to improved
primary tumor response, improved tolerance, and
improved delivery.
Introduction
As our understanding of the management of rectal cancer
evolves, the tools available to stage and treat these patients
are ever-increasing in number. Just a decade ago, staging and
treatment were relatively straightforward. Patients were
staged with endoscopy to assess tumor location, transrectal
ultrasound (TRUS) to determine depth of tumor invasion (T
stage) and lymph node status (N stage), and cross-sectional
imaging (typically computed tomography, CT) to assess for
distant metastatic disease (M stage). Based on these results,
patients were offered one of two options for denitive therapy: patients with early stage tumors (cT1-2N0M0) went
directly to surgery, and patients with locally advanced tumors
S. R. Hunt · M. G. Mutch (*)
Washington University School of Medicine, Department of
Surgery, St. Louis, MO, USA
e-mail: mutchm@wustl.edu
(cT3-4N0 or cTXN1-2M0) received neoadjuvant therapy
followed by surgery. The options for neoadjuvant therapy
were limited to long-course radiation and chemotherapy,
with short-course radiation therapy being used in parts of
Europe and sparingly in the United States. Systemic chemotherapy was typically the last mode of therapy received by
rectal cancer patients. Trimodal therapy combining pelvic
radiation, surgery, and chemotherapy evolved into the current “standard of care” for patients with locally advanced
rectal cancer (LARC).
Improvements in rectal cancer staging, systemic chemotherapy, and our understanding of the effects the components
of trimodal therapy had on both local and systemic disease
have allowed for signicant changes in how we utilize these
three modes of therapy. The treatment paradigm of longcourse chemoradiation therapy followed by surgery, and then
systemic chemotherapy is being challenged.
Historical rates of local pelvic failure for LARC were
upward of 25%, but the introduction of strict surgical technique and neoadjuvant chemoradiation therapy has consistently lowered the rate to between 5% and 10% [1–4].
Despite these improvements in local control, neoadjuvant
radiation and optimal surgery have not translated into consistently improved overall survival [5–7]. Patients with LARC
(stage II and III) currently have a 30–40% risk of distant failure, which is the most frequent cause of cancer-related death
in this population [8]. Many have hypothesized that the lack
of improvement in survival is a result of the long time period
between initiation of neoadjuvant therapy and the delivery of
multidrug systemic chemotherapy, which can be up to
20 weeks. These issues have led to studies examining the
most appropriate timing and sequence of the three treatment
modalities. First, distant recurrence is a result of occult
micrometastases, and the longer they are left untreated, the
greater the chance they have of surviving and establishing
growth in a distant site [9]. Second, in attempting to dene
the most appropriate timing of surgery after radiation therapy, it has become clear that longer “resting” intervals have
© Springer Nature Switzerland AG 2022
S. R. Steele et al. (eds.), The ASCRS Textbook of Colon and Rectal Surgery, https://doi.org/10.1007/978-3-030-66049-9_26
463
464
S. R. Hunt and M. G. Mutch
led to a greater response rate of the primary tumor [10–13].
Third, the introduction of oxaliplatin to the systemic treatment of colorectal cancer has demonstrated an improvement
in tumor response compared to 5-FU alone [14, 15]. Finally,
the concept of organ preservation is becoming more accepted
in patients who have a clinical complete response to neoadjuvant therapy [16]. As a result of these observations, there
has been a dramatic change in rectal cancer treatment,
namely, the utilization of multidrug systemic chemotherapy
in the neoadjuvant setting and the introduction of the concept
of total neoadjuvant therapy (TNT). This chapter will focus
on the history of neoadjuvant therapy, the evolution of the
use of systemic chemotherapy in the neoadjuvant setting,
and the concept of total neoadjuvant therapy (TNT).
Rectal Cancer Staging
For the purposes of this chapter, staging will be discussed
only in relation to determining the need for neoadjuvant therapy. Systemic staging is important, as knowledge of the presence of distant metastatic disease may impact decisions
regarding the use and timing of all three modalities of therapy– surgery, radiotherapy, and chemotherapy. Locoregional
staging in rectal cancer is important for planning operative
therapy and for making the decision as to whether the patient
should be treated with neoadjuvant therapy. TRUS had been
used in rectal cancer staging for the better part of the last
30years, but because of its operator dependence, technical
challenges, and only moderate accuracy, it has been supplanted in the last decade by magnetic resonance imaging
(MRI), especially for locally advanced tumors. Currently,
pelvic MRI is the recommended imaging modality for accurate local staging of rectal cancer [17]. It provides information regarding tumor size and location, the relationship of the
tumor to the sphincter complex and peritoneal reection,
evidence of extramural vascular invasion, and invasion of
other pelvic structures. Most importantly, MRI denes the
relationship of the tumor to the mesorectal fascia. This is
often termed the “circumferential resection margin (CRM)”
by radiologists, although obviously the true CRM can only
be determined histologically. On MR, the CRM is dened as
the closest distance of the tumor to the mesorectal fascia. It
is thus assumed that the surgeon will be able to accurately
mobilize the rectum and mesorectum in this plane. The CRM
is considered threatened or involved when the tumor extends
within 1mm or less of the mesorectal fascia and breaches the
mesorectal fascia or for lower tumors, when they invade the
intersphincteric plane [18]. The signicance of the CRM,
and more specically an involved CRM, to local recurrence
and overall survival in rectal cancer patients has been elucidated with increasing clarity over the past three decades
[18–21]. Local recurrence is signicantly higher in patients
with a positive CRM than without [18, 22]. Furthermore,
with decreasing distance to the CRM, there is a dramatic
increase in rates of local recurrence, metastasis, and death
[18]. MRI has emerged as consistently superior to either
TRUS or CT scan for CRM assessment, while offering comparable assessment of both T and N stage [23]. In patients
who have contraindications to MRI, the combination of
physical exam, TRUS, and a pelvic CT scan can provide
adequate information to guide therapy.
There are no widely agreed upon recommendations for
restaging the primary tumor following neoadjuvant therapy.
Patients with a threatened or involved CRM on initial staging
exam may benet from restaging [17]. In these patients,
treatment-related tumor retraction from the CRM portends
an improved prognosis [21]. However, there have been very
little data to support the concept that local restaging will
change operative strategy in patients initially presenting with
locally advanced tumors. Because neither radiotherapy nor
chemotherapy kill in a “wave front” and isolated nests of
viable tumor can persist in the original volume of tumor, the
surgeon should plan on resecting all tissue that was originally involved with tumor. The major exception to this recommendation regarding restaging is when one is considering
nonoperative management after neoadjuvant therapy (denitive chemoradiotherapy, “watch and wait”).
The National Comprehensive Cancer Network (NCCN)
provides a formal denition of the rectum as beginning at a
virtual line between the sacral promontory and the top of the
pubic symphysis and ending at the palpable upper border of
the anorectal ring [17]. While this denition is important in
differentiating rectal cancer from colon cancer, it is not
intended to mandate which tumors should be treated with
neoadjuvant therapy. Suitability for neoadjuvant radiation
often depends on the nation in which the patient is presenting. In the United States, the NCCN guidelines recommend
neoadjuvant radiation for all clinical stage II and III patients
[17]. The European Society for Medical Oncology (ESMO)
allows for patients with early cT3 cancers (invading less than
5mm beyond muscularis propria) to be treated with proctectomy alone [24]. The ESMO guidelines even permit surgery
alone for patients with clinical N1 disease in the upper and
mid-rectum, provided that the circumferential resection margin appears free on imaging.
History of(Neo)Adjuvant Therapy
For over 100 years, radiation has been used to varying
degrees in the treatment of rectal cancer. In the early twentieth century, surgery was used only for salvage, as it was
extremely morbid. Over time, as operative and anesthetic
techniques improved, surgery became the mainstay for the
treatment of rectal cancer. In the early 1980s, William Heald
published multiple papers describing his technique and
excellent local control with what he described as “total
26 Rectal Cancer: Neoadjuvant Therapy
465
mesorectal excision” (TME), which emphasized the concept
of removing the appropriate amount of mesorectum in its
fascial envelope, using precise technique with good visualization [1]. This was not a novel concept, but not routinely
practiced by many surgeons at the time, who often removed
the rectum bluntly, potentially threatening the CRM and
leaving involved mesorectal nodes in situ. Despite the publications of Heald and others, widespread adoption of TME
technique was slow, and surgery at that time had a high local
recurrence rate. This high local recurrence rate prompted
multiple trials aimed at using radiation to improve local
control.
Two competing schools of thought emerged on the use of
radiation in rectal cancer. Advocates for preoperative radiation touted the ability of radiation to shrink tumors prior to
surgery. This camp argued that tissue oxygenation, which is
requisite for maximal radiation efcacy, was adversely
impacted by scarring postoperatively. Additionally, neoadjuvant delivery would minimize radiation damage to the small
bowel and neorectum, as pelvic adhesions would be fewer
and small bowel xation in the pelvis less, in the preoperative period. Those supporting the concept of selective postoperative radiotherapy noted that the inherent inaccuracies
of staging would lead to overtreatment of many patients and
also commit some patients with lower stage tumors to adjuvant chemotherapy because the true tumor stage would be
difcult to differentiate. There was also signicant fear that
preoperative delivery would lead to increased anastomotic
and wound complications. Delay of surgery, which was the
mainstay of therapy, was also cited as a reason to delay radiation until after surgery. While early trials demonstrated the
value of radiation in both the preoperative [25, 26] and post-
operative setting [27–29], it would take years before the optimal timing of radiation would be established.
Adjuvant Radiation
The initial early large trials for rectal cancer used radiation
alone in the adjuvant setting. The Medical Research Council
Rectal Cancer Working Party in the United Kingdom found
that radiation delivered in the postoperative setting decreased
the local recurrence rate by 50% when compared to surgery
alone [30]. Meanwhile, several invitro and animal studies
demonstrated that 5-uorouracil (5-FU) enhanced the effectiveness of radiation on various tumor cell lines [31, 32].
Additionally, the Mayo Clinic demonstrated that combining
5-FU with radiation improved palliation in patients with
recurrent or unresectable rectal cancer [33]. With this background, various groups began to explore the use of combined
chemoradiation in trials.
In the United States, the Gastrointestinal Tumor Study
Group performed a prospective randomized study comparing surgery alone to surgery plus adjuvant therapy with either
chemotherapy, radiation, or combined chemoradiation [29].
While the study was small and likely underpowered, it did
show that postoperative radiation combined with chemotherapy conferred a signicant 24% survival advantage over surgery alone.
The North Central Cancer Treatment Group (NCCTG) set
out to determine if chemotherapy and radiation were more
effective than radiation alone in the adjuvant setting [34].
Patients were randomized to groups receiving radiation alone
or chemotherapy and chemoradiation. The radiation was
delivered over 5 weeks to a total dose of 45 Gy, and most
patients received a 5.4Gy boost to the tumor. The patients in
the combined chemotherapy and chemoradiation group
received systemic chemotherapy with 5-FU and semustine
(methyl CCNU) for several cycles and then radiation combined with bolus 5-FU, administered early and late during
the course of radiation. This group was also given more systemic chemotherapy after the chemoradiation. With 204
patients enrolled, the authors demonstrated signicant
improvements in disease-free survival, local recurrence,
cancer- related death, and overall survival in the combined
chemotherapy and chemoradiation group. While there was
no difference in the severe side effects between groups, the
chemoradiation group suffered more gastrointestinal and
hematologic toxicities.
Following the release of these study results, the National
Institute of Health convened a Consensus Conference on
colorectal cancer. It was the overwhelming opinion of the
conference that both adjuvant radiation and chemotherapy
should be part of the treatment of locally advanced rectal
cancer. This was released as a Consensus Statement in 1990,
published in the Journal of the American Medical Association
[35]. In the manuscript, the authors point out that semustine
had signicant leukemogenesis and nephrotoxicity, and they
were emphatic that future studies should attempt to nd
adjuvant regimens that did not use semustine. Following
release of the 1990 NIH consensus statement, many patients
with rectal cancer were then given adjuvant chemoradiotherapy, although the vast majority of it was administered in the
postoperative setting.
Seeking to deliver adjuvant chemoradiation in a more
effective and more tolerable regimen, the Gastrointestinal
Intergroup performed a 2×2 clinical trial comparing postoperative chemoradiation with bolus 5-FU to chemoradiation
to chemoradiation with infusional 5-FU delivered over the
entirety of the radiation treatment [36]. Additionally, they
evaluated the use of semustine delivered before and after
chemoradiation because of semustine’s signicant toxicities.
This was a large multi-institute trial involving 660 patients
with stage II and III rectal cancers. All patients received systemic chemotherapy with 5-FU (+/− semustine) both before
and after chemoradiation. The trial showed that there was a
signicantly increased time to recurrence in the group that
received the 5-FU as a constant infusion. Additionally, the
466
S. R. Hunt and M. G. Mutch
authors found no benet to the addition of semustine to the
systemic chemotherapy regimen. They concluded that infusional 5-FU was superior to bolus 5-FU and that semustine
was not necessary in the adjuvant regimen for rectal cancer.
While it was clear that adjuvant therapy conferred a signicant benet to rectal cancer patients, it had not been
denitively proven that the addition of radiation to adjuvant
chemotherapy was more helpful than chemotherapy alone.
The National Surgical Adjuvant Breast and Bowel Project
(NSABP) R-02 was a large trial designed to address this
question [37]. As with the trials discussed above, in the radiation group, systemic chemotherapy was given before and
after postoperative chemoradiation. The authors demonstrated that the addition of radiation to systemic chemotherapy signicantly improved local control but did not affect the
incidence of distant disease or overall survival.
Neoadjuvant Radiation
Meanwhile, advocates for preoperative radiation had been
working diligently to prove the value of administering radiation prior to surgery. Out of fear that radiation would lead to
signicant postoperative complications, early trials used
relatively low doses (<20 Gy), and none of these studies
showed signicant improvement inlocal control or overall
survival as compared to surgery alone [38–40].
Eventually, higher doses of preoperative radiotherapy
were utilized. The European Organization for Research and
Treatment of Cancer (EORTC) demonstrated that preoperative delivery of 34.5 Gy of radiotherapy reduced the local
recurrence rate from 30% to 15% when compared to surgery
alone. This was one of the rst large prospective studies to
show a benet to neoadjuvant radiation. While there was a
trend toward improved survival, it was not signicant. The
authors did caution that such a “large” dose of radiation in
the neoadjuvant setting may have signicant morbidity in
elderly and medically frail individuals [41].
The Medical Research Council Rectal Cancer Working
Party evaluated the use of neoadjuvant radiation for potentially operable xed and tethered tumors [42]. These patients
were chosen because the tumors were likely to be higher
stage, minimizing the chance of overtreatment. Patients were
randomized to surgery alone or radiation followed by surgery. Patients in the treatment group were given 40Gy in 20
fractions, and surgery was delayed by at least 4weeks. There
was no difference in postoperative complications between
the groups. The authors showed a signicant improvement
in local control and disease-free survival in the patients
treated with neoadjuvant radiation followed by surgery as
compared to patients treated with surgery alone.
The Uppsala Trial compared preoperative and postoperative radiation delivery in what was the largest comparative
trial at that time [43]. Patients randomized to the preopera-
tive radiation group were treated with 25.5Gy over 5–7days
followed by immediate surgery. Patients assigned to the
postoperative treatment group were given radiation only if
their pathologic stage was stage II or III. They were then
treated with 60Gy over 8weeks. Local recurrence rates were
signicantly better in the neoadjuvant group (12% vs 21%).
Despite the improvement inlocal control, the study showed
no survival advantage to preoperative radiation. The authors
did note that half of the patients assigned to the postoperative
treatment group had delayed radiation therapy due to prolonged recovery from surgery.
The Foundation Trials
The foundation for the use of neoadjuvant radiation that is
commonly used today arises primarily from three sequential
publications around the turn of the century in the New
England Journal of Medicine. The rst of these studies was
the Swedish Rectal Cancer Trial [3]. Based on the results in
the Uppsala Trial, the study designers compared surgery
alone to neoadjuvant short-course radiation followed by
immediate surgery. This large randomized trial was offered
to patients with resectable rectal cancer for whom abdominal surgery was planned. All patients had a minimum of
5years of follow-up. Nearly one-third of the patients in the
trial had stage I disease. The results showed a signicant
and dramatic decrease inlocal recurrence in those treated
with neoadjuvant short-course radiation (11% vs 27%).
There was also a difference in overall and disease-free survival, favoring those in the neoadjuvant radiation group.
Critics of the trial, many of whom believed that precise surgery alone was sufcient treatment for rectal cancer, argued
that the local pelvic failure rate in the surgery alone group
was too high. They contended that the trial only proved that
radiation mitigated problems related to poor surgical technique. Moreover, there were signicantly more stage I and
stage II patients in the radiation/surgery group than in the
surgery alone group. Even though patients were treated with
short-course radiation and immediate surgery, the authors
attributed these differences to tumor downstaging from
radiation.
Soon after the Swedish trial was published, another large
national study addressed some of its shortcomings. The
Dutch Colorectal Cancer Group essentially repeated the
Swedish Rectal Cancer Trial, randomizing patients to surgery alone versus preoperative short-course radiation followed by immediate surgery [2]. However, the trial designers
recognized the importance of standardizing and optimizing
surgical technique. Participating surgeons were required to
attend workshops and symposia on “TME surgery” and
watch instructional videos and were monitored by specially
trained expert surgeons. Specically, the rst ve proctectomy procedures at each institution were proctored. In addi-