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420 R. Bleday and J. Garcia-Aguilar
Certain clinical features also may have an impact on decisions about the appropriate therapy. Patients with physical
handicaps may have significant difficulty in managing a
stoma. Body habitus and patient gender influence the surgeon’s ability to perform a sphincter-saving operation
because of pelvic anatomy. Whereas a sphincter-saving procedure in a multiparous thin female can be straightforward,
performing a low anastomosis in an obese male with a narrow
pelvis can be extremely difficult. A history of pelvic irradiation or nonrectal pelvic malignancy can make a rectal
resection and sphincter preservation more difficult.
In summary, each patient with rectal cancer should be
viewed individually and a technical plan for their resection
customized to their stage, gender, age, and body habitus
(Figure 30-3). With these issues in mind, the technical choices
for a radical resection are discussed below. In all of these
resections, a TME should be performed. Local treatments are
then described in detail.
Techniques of Rectal Excision
Abdominoperineal Resection
The APR was the first radical resection described by Miles in
1908 (reprinted in 1971).
be achieved with any radical resection. These principles
included:
●
Removal of the whole pelvic mesocolon
●
Removal of the “zone of upward spread” in the rectal
mesentery
●
Wide perineal dissection
●
An abdominal anus
●
Removal of the lymph nodes along the iliacs
Four of five of these principles are the anchor of our technique
even today (the dissection along the iliacs is not done routinely).
Candidates for an APR are patients whose tumors are either
into the anal sphincter or are so close to the anal sphincter that
a safe distal margin cannot be obtained. Also, there is a small
subset of patients with mid rectal tumors but with poor continence that benefit from an APR even though they are technically sphincter-preservation candidates. There have been
recent reports that obturator/pelvic sidewall lymph nodes are
more often involved in patients with very low rectal cancers.
It has been suggested that these patients should undergo an
extrafascial TME dissection.
to this concept, we describe herein the typical APR with
TME, excision of the sphincter and levators, and creation of a
permanent colostomy.
Position
Usually a patient is placed in the lithotomy position. We often
elevate the mid and upper sacrum off the bed with a blanket
72
Miles set out several principles to
73
Although there is some merit
or a towel so that the coccyx is away from the bed and therefore able to be more easily prepped into the field.
Incision and Exploration
The abdomen is usually entered through a midline incision. In
thin patients, the incision can often be kept below the umbilicus. Low transverse incisions can also be performed as long
as the ostomy site is not compromised. The APR is also a
good application of laparoscopic-assisted surgery. The
abdominal portion of the procedure can be performed using
laparoscopic techniques with extraction of the specimen
through the perineum. It has yet to be shown, however,
whether there is any value added with the laparoscopicassisted approach.
The exploration of the abdomen and pelvis should be the
first step after accessing the abdomen. The liver, aortic lymph
nodes, superior hemorrhoidal lymph nodes, iliac lymph
nodes, and the pelvis should all be examined. A large tumor
burden, particularly multiple peritoneal implants, should lead
to a reassessment of the need for resection and perhaps only a
colostomy should be performed.
Mobilization
To excise the whole pelvic mesocolon and “zone of upward
spread,” the sigmoid colon and left colon need to be mobilized. The mobilization begins along the left pelvic brim. The
gonadal vessels, ureter, and iliacs are reflected toward the
retroperitoneum and the colon and mesocolon are pulled
toward the midline. The left colon is mobilized but the splenic
flexure rarely needs to be taken down. The dissection then is
started on the right pelvic brim. Often, one can identify the
sympathetic nerve trunks behind the superior hemorrhoidal
artery (SHA) as one mobilizes the rectal mesocolon away
from the sacral promontory.
Resection and Ligation
After mobilization of the mesentery, the bowel is divided near
the sigmoid colon/left colon junction at right angles to the
blood supply (Figure 30-4). Because a high ligation of the
SHA or of the IMA is planned, the blood supply to most of
the sigmoid colon will be compromised. For most cases, a ligation of the SHA flush with the left colic artery should be performed. A higher ligation of the IMA should be performed if
there is any question of lymph node involvement outside
the pelvis (e.g., palpable nodes along the SHA up to or
above the left colic artery). The IMA should be ligated flush
with the aorta and the inferior mesenteric vein should be ligated near the ligament of Treitz. A high ligation may also be
required for additional colonic mobilization.
After dividing the bowel, sequential clamps of the sigmoid
vessels are placed and the mesentery is ligated and divided. A
high ligation is performed of the SHA with care being taken
30. Surgical Treatment of Rectal Cancer 421
FIGURE 30-3. Treatment options for rectal cancer depending on stage and location.
Stage I (T1N0, T2N0—The cancer is confined to the rectal wall and no nodes are involved)
●
Distal rectal cancers: T1 (invasion into the submucosa only)
■
Local excision
■
Radical resection, often an APR
■
Adjuvant therapy is usually not recommended.
●
Distal rectal cancers: T2 (invasion into the muscularis propria)
■
Local excision with preoperative or postoperative adjuvant therapy
■
Radical resection without adjuvant therapy, often an APR
●
Mid rectal cancer: T1
■
TEM
■
Radical resection, usually an LAR with low anastomosis. A temporary proximal diverting ostomy is often required.
■
Adjuvant therapy is usually not recommended.
●
Mid rectal cancer: T2
■
TEM with either preoperative or postoperative adjuvant therapy
■
Radical resection similar to a T1 cancer
■
Adjuvant therapy is not recommended if a radical resection is performed but is recommended after a TEM resection.
●
Upper rectal cancers: T1 and T2
■
LAR
Stage II and Stage III cancers [Stage II cancers have invasion into the mesorectal fat (T3) but no involved mesorectal lymph nodes. Stage III
cancers are any rectal cancer (T1, T2, or T3) but with involved lymph nodes.]
●
Distal rectal cancers
■
Preoperative adjuvant therapy is most often recommended followed by a radical resection, usually an APR.
■
If preoperative imaging does not clearly define the stage of the cancer, resection can be done first followed by postoperative adjuvant
therapy.
●
Mid rectal cancers
■
Same as above for distal rectal cancers except an LAR is usually performed instead of an APR.
●
Upper rectal cancers
■
LAR, with either preoperative or postoperative adjuvant therapy
Stage IV cancers
●
Treatment for any cancer is dependent on the extent of metastasis. With better surgical and medical treatments for metastatic disease,
locoregional control of the primary should be aggressive and similar to the above recommendations except in the most advanced cases.
(Key: LE, local excision; short XRT, short-course radiation therapy given 2 times a day for 5 days in larger fractions; ChXRT, long-course
therapy given in 30 smaller fractions over 6 weeks in combination with chemotherapy)
422 R. Bleday and J. Garcia-Aguilar
often a tough “ligament” that traverses the mesorectum at this
point. It theoretically contains the middle rectal artery.
74
However, in a study by Jones et al.,
this artery is only pres-
ent to any significance about 20% of the time.
The anterior dissection is perhaps the most difficult. In
men, one should try to include the two layers of
Denonvillier’s fascia. This fascia is composed of peritoneum
that has been entrapped between the seminal vesicles and
prostate anterior and the rectum posterior (Figure 30-5). In
woman, the peritoneum at the base of the pouch of Douglas is
incised and the rectovaginal septum is then separated.
If done properly, the mesorectum begins to appear as a
bulky bilobed structure. As one progresses distally beyond the
mid rectum, the mesorectal fat begins to attenuate. At the
pelvic floor there is often only a thin layer of mesorectal fat
around the bowel.
The Perineal Dissection
As the abdominal procedure proceeds distally, the perineal
dissection can commence. Before the preparation and draping
of the patient, the position of the perineum is ensured so as to
allow a wide elliptical incision around the anus. The rectum is
usually cleared of any stool or residual preparation and the
anus is sewn closed. The incision for the perineal dissection
starts anteriorly at the perineal body, goes laterally to the
ischiorectal spines, and then finishes posteriorly at the tip of
the coccyx. After incising the skin and subcutaneous
ischiorectal membrane and fat, the levators are then encountered. The perineal surgeon then coordinates their dissection
FIGURE 30-4. The vascular supply of the sigmoid and rectum. A typical ligation is performed at the junction of the SHA and left colic
artery. In patients with a clinical suspicion of positive nodes at the
level of the IMA or if vascular mobilization is needed for the left and
transverse colon, then a ligation of the IMA is performed at the aorta.
with the abdominal team in the posterior precoccygeal plane.
A pair of long scissors is used to divide the ligaments in the
to not injure the ureters, and also to make sure that the sympathetic nerve trunks are preserved.
The TME
A successful TME starts with the proper ligation of the SHA
or IMA. As one dissects down toward the sacral promontory,
the sympathetic nerve trunks are identified. The dissection
plane is just anterior or medial to these nerves. Using the
cautery or scissors, the nerves are reflected toward the pelvic
sidewall while the mesorectal fascia surrounding the mesorectal fat is kept as an intact unit. The dissection starts posteriorly
and then at each level proceeds laterally and then anteriorly. In
the mid rectal area along the lateral sidewalls, one can sometimes see the parasympathetic nerves tracing anteriorly toward
the hypogastric plexus. The plexus is usually on the anterolateral sidewall of the pelvis, just lateral to the seminal vesicles
in the man and the cardinal ligaments in the woman. There is
FIGURE 30-5. Sagittal view of the rectum, bladder, Denonvillier’s fascia, and the prostate. The dissection should proceed anterior to one
or both layers of Denonvillier’s fascia.
30. Surgical Treatment of Rectal Cancer 423
posterior midline behind the rectum. Once a connection has
been opened, the perineal surgeon places their finger above
the levators and “hooks” them down toward the perineal field.
The levators are then divided with the cautery. The dissection
starts posteriorly and then proceeds laterally and anteriorly.
Often it is best to complete the anterior dissection after the
proximal portion of the specimen has been everted out to the
perineal surgeon. The remaining attachments in the anterior
plane are then divided with the cautery. Once the specimen is
removed, hemostasis is ensured with the cautery or
absorbable figure-of-8 sutures. Typically there are vessels that
need to be ligated in the crease between the lateral prostate
and the pelvic floor.
After irrigating the pelvis, one reapproximates the residual
levators with absorbable sutures and then the subcutaneous
fat, ischiorectal fat, and skin are closed in several layers.
Drains in the pelvis can be brought out through the pelvis or
via the abdomen.
Closure
With the specimen removed, attention is turned to creating an
ostomy. Ideally, the patient has been marked by a certified
ostomy therapist preoperatively. The end of the colon is carefully cleaned of any fat. The skin is divided in a circular shape
at the ostomy site. A core of fat is removed from the subcutaneous tissues. The fascia is divided in a cruciate manner. The
muscle is split but not divided, and then the peritoneum is
incised. The hole is made wide enough to accommodate the
bowel and the accompanying mesentery. The bowel should
then be brought up through the opening so that it is 1–3 cm
higher than the skin.
After creating the ostomy, pelvic drains are placed. These
keep fluid from leaking through the perineal closure and
allow for better healing and a reduced risk of a perineal hernia. The midline fascial opening is then closed and the skin
approximated. After skin closure and placement of the dressing, the ostomy is then matured.
LAR with Sphincter Preservation
Sphincter-sparing procedures for resection of mid and some
distal rectal cancers have become increasingly prevalent as
their safety and efficacy have been established. The advent of
circular stapling devices is largely responsible for their
increasing popularity and utilization. An LAR involves dissection and anastomosis below the peritoneal reflection with
ligation of the superior and middle hemorrhoidal arteries. An
extended LAR indicates complete mobilization of the rectum
down to the pelvic floor with division of the lateral ligaments
and posterior mobilization through Waldeyer’s fascia to the
tip of the coccyx. Additionally, there is dissection of the
plane between the anterior rectal wall and the vagina in a
female patient and dissection of the plane between the rectum
and the prostate in a male patient to a level distal to the
inferior margin of the prostate gland. As long as the surgeon
can obtain a distal margin of at least 2 cm, an anastomosis can
be considered appropriate if technically feasible. Body habitus, adequacy of the anal sphincter, encroachment of the
tumor on the anal sphincters, and adequacy of the distal margin are all factors in determining the applicability of a sphincter-sparing operation.
Coloanal Anastomosis
The ultimate procedure in sphincter-saving operations is the
ultra LAR with coloanal anastomosis. This operation preserves the sphincter mechanism in patients with very lowlying rectal cancer in whom the distal margin is at the
minimally acceptable level yet adequate for cancer clearance.
These operations are reserved for patients who have a distal
rectal cancer that does not invade the sphincter musculature
and in whom a standard extended LAR is technically not
possible. After an adequate distal margin is achieved, the rectum is transected at the level of the pelvic floor musculature.
The remaining anal mucosa between the dentate line and the
level of transection of the pelvic floor can then be “stripped”
and an anastomosis between the colon and the anus is performed to restore continuity. Alternatively, the procedure can
be started at the dentate line with a tubular mobilization of
the distal rectum in the intersphincteric groove. This perineal
resection can proceed up to the superior margin of the puborectalis muscle before dissecting into the pelvis and connecting with the pelvic and abdominal dissection. The
procedure usually requires full mobilization of the splenic
flexure, such that the vascular supply of the left colon now
based on the middle colic vessels can reach the distal pelvis.
The coloanal anastomosis can also be done with a colonic
J pouch. Because of the larger capacity of the J pouch
construction, anorectal function is thought to be improved,
especially early after the surgery. The J pouch is created by
folding the distal end of the colon back on itself approximately 5–8 cm and then creating a common channel
(Figure 30-6). The actual anastomosis to the anus is then
done from the apex of the J in side to end manner. An alternative to the colonic J pouch is the coloplasty. This technique
is similar in concept to a stricturoplasty. The distal colon is
divided in a longitudinal direction for 8–10 cm starting 4–6
cm from the distal edge of the pedicle. The longitudinal incision is then approximated transversely making a larger reservoir capacity (Figure 30-7). The technique can decrease
frequency in the early postoperative period but it has been
associated with an increased number of anastomotic leaks.
A proximal diverting stoma is advisable because of the
potential for an anastomotic leak or vascular compromise of
the left colon. Contraindications to the procedure include
baseline fecal incontinence from deteriorated anal sphincter
muscles; tumor invasion of the anal sphincter musculature or
rectovaginal septum; tenesmus; and technical factors such as
body habitus, tumor location, and tumor size.
424 R. Bleday and J. Garcia-Aguilar
79
10%.
Radical surgery, especially the APR, leads to a significant change in body image and social habits. In a patient survey performed in 1983 by Williams and Johnston,
80
66% of
patients complained of significant leaks from their stoma
appliances, 67% experienced sexual dysfunction, and only
40% of patients who were working preoperatively returned to
their jobs after their operation. Also, radical surgery does not
guarantee a recurrence-free survival. The 5-year survival rate
in the National Cancer Data Base for Stage I disease is 78%.
The complication rates, the change in body image with a
colostomy, and the improvements in patient selection secondary to innovations in preoperative imaging modalities have led
to a renewed interest in local excision of rectal cancers.
History
The first descriptions of local excision for rectal cancer date
back to the late 1800s. At this time, there was little knowledge
FIGURE 30-6. Construction of a colonic J pouch after an ultra LAR.
The distal colon pedicle is folded back on itself to make a “J.” A common channel is then created using a stapling device that will staple and
divide. A larger reservoir is then created. The J pouch is then anastomosed to the anus using a circular stapler or in a hand-sewn manner.
Local Excision
Although the LAR and the APR are the mainstays of therapy
for many distal rectal cancers, the radical resection is associated with significant morbidity and mortality. A review of the
literature showed that mortality rates for the APR range from
0% to 6.3%,
postoperative complications.
cations are urinary dysfunction and perineal wound infections,
with rates as high as 50% and 16%, respectively.
rience, the incidence of major wound complications was
75,76
with some studies having a 61% incidence of
77
The majority of these compli-
78
In our expe-
of the natural history of rectal cancer, and local excisions
were viewed as the safest approach. In 1908, Miles
high recurrence rate associated with local excision and developed a radical resection that was in keeping with the oncologic principles of the time. It was believed that radical
resections such as Miles’ APR provided the best opportunity
for cure, and this radical resection quickly became the standard of care despite its increased morbidity and mortality over
local excisions.
The first significant series published describing the use of
local excision for rectal cancer was by Morson and col-
82
leagues
at St. Marks Hospital in London. Local excision had
been used on patients who had either refused a colostomy or
were deemed medically unfit for a radical operation secondary to comorbidities. In this series, they reported at the time
of excision 91 patients with negative margins, and in the
patients with negative margins only two had local recurrence
whereas one had a distal recurrence. However, for the 69
patients with positive margins, 13 had a local recurrence and
72
noted a
81
FIGURE 30-7. Construction of a coloplasty. The bowel is divided in a longitudinal manner as shown and resutured transversely to create a
larger reservoir capacity.
30. Surgical Treatment of Rectal Cancer 425
T
one had distant recurrence. Most of the patients who underwent a local excision had T1 lesions. With these results, a
“policy” was proposed to offer local excision to carefully
selected patients with early small distal rectal cancers with
well or moderately differentiated tumors.
82
These results
prompted a renewed interest in local excision because they
showed that local recurrence and survival rates were similar
to those of APR for these small distal cancers, whereas the
morbidity was greatly reduced.
ABLE 30-1. Properties of distal rectal adenocarcinoma amenable to
local excision for curative intent
Physical features
Tumors <4 cm in diameter
Tumor <40% of bowel circumference
Tumor within 10 cm of dentate line
Tumor freely mobile on digital rectal examination
ERUS
T1, T2 lesions
No regional lymph node involvement
124
Preoperative Evaluation
Proper patient selection remains the key to successful local
excision of rectal cancers. The retrospective literature shows
that there is a direct correlation between local recurrence and
specific pathologic tumor features including depth of invasion, lymphatic invasion, histologic grade, and most importantly clear negative margins at the time of resection. In the
past, preoperative evaluation relied solely on the DRE, which
was found to have some success in demonstrating depth of
invasion.
83,84
Recent studies have refuted this evidence,85and
there are currently a number of imaging studies that can aid in
the preoperative staging of rectal cancers, including ERUS
and eMRI.
Preoperative evaluation begins with a thorough history and
physical, taking care to note sphincter function, because local
excision in the setting of poor preoperative sphincter function
may be inappropriate. A digital rectal examination should be
performed to assess the distance of the tumor from the anal
verge, as well as its size and mobility. Tumors amenable to
local excision should be <4 cm in diameter and occupy <40%
of the bowel circumference. The distance of the tumor from
the dentate line is important, because it will dictate which
approach should be taken. Tumors <5 cm from the dentate are
amenable to resection via a transanal procedure, whereas
tumors in the middle third of the rectum may require a
transcoccygeal approach or transanal endoscopic microsurgery (TEM). Immobile tumors are likely transmural, and
thus not candidates for local excision. The overall health of
the patient must be taken into account, because patients who
are considered medically unfit for a major resection are often
good candidates for local excision.
Imaging for rectal cancer has already been discussed.
Suffice it to say that imaging is especially critical in selecting
patients for a local excision. The best candidates have either a
T1N0 or a T2N0 lesion. For the T2 lesions, local excision
alone is not sufficient as therapy alone, and either preoperative
or postoperative adjuvant therapy should be added. The selection criteria for a local excision are summarized in Table 30-1.
Technique
Historically, there are three approaches to local excision of
rectal cancer: transanal, transcoccygeal, and transsphincteric.
The transsphincteric approach has been associated with fecal
incontinence secondary to sphincter dysfunction, and thus has
fallen out of favor. Recently, a newer technique, TEM, has
provided a minimally invasive option for local excision which
also allows the operator to reach lesions that are located more
proximally and would have required a transcoccygeal or
transsphincteric approach in the past.
Transanal Excision
Local excision can be accomplished via a transanal approach
for the majority of low rectal cancers. In our prospective study
of 48 local excisions for rectal cancer, 33 were performed
using a transanal approach.
patients should receive a full mechanical and antibiotic bowel
preparation. After induction of anesthesia, the patient is
flipped over and placed in the prone-jackknife position, with
the buttocks taped apart. A pudendal nerve block should then
be administered, which aids in postoperative pain control and
more importantly relaxes the sphincter complex. An anal
retractor alone or in combination with a retractor with selfretaining hooks are then used to dilate the anus and expose the
lesion. Once adequate visualization has been obtained, traction sutures are often placed 1–2 cm distal to the tumor, and
the line of dissection is marked on the mucosa using electrocautery. This line of dissection should be approximately
1–2 cm from the border of the tumor circumferentially
(Figure 30-8). If visualization is not initially adequate, serial
traction sutures should be used to prolapse the lesion into the
field of view. Next, the electrocautery is used to make a fullthickness incision along the previously marked mucosa
(Figure 30-8B). Upon completion of this incision, the perirectal fat should be visible beneath the lesion to confirm a fullthickness excision. In anterior lesions, care must be taken not
to injure the back wall of the vagina in females, or the prostate
in males. The lesion is then excised leaving visible perirectal
fat at the base of the lesion. The defect in the bowel wall is
then closed transversely using interrupted 3-0 polyglycolic
sutures.
The complications most closely associated with transanal
excisions include urinary retention, urinary tract infections,
delayed hemorrhage, infections of the perirectal and
ischiorectal space, and fecal impactions. However, the overall
incidence of these complications is quite low, and the mortality rate is 0% in most series.
86
Before local excision, all
426 R. Bleday and J. Garcia-Aguilar
then removed with occasional bleeding from an extension of
the middle sacral artery, which is easily controlled with electrocautery. The levator ani muscles will now be visible at the
base of the wound and should be separated in the midline,
exposing a membrane that resides just outside of the perirectal fat. Division of this membrane allows for complete mobilization of the rectum within the intraperitoneal pelvis.
For posterior-based lesions, the distal margin of the tumor
can be palpated via a rectal examination, and then the
mesorectum and rectum are transected at a point 1–1.5 cm distal to the tumor (Figure 30-9). The excision is then completed
with a 1-cm margin surrounding the lesion. For posterior
lesions, the transcoccygeal approach allows for the removal of
perirectal nodes that lie in the surrounding mesorectal tissue.
For anterior lesions, a posterior proctotomy is made, and then
the lesion is approached under direct vision, again excising the
lesion down to the perirectal fat with a 1-cm margin (Figure
30-10). After removal, the specimen is reoriented for the
FIGURE 30-8. Transanal excision. A A transanal excision is performed by marking out a 1 cm or greater margin around the tumor.
B A full-thickness excision is then performed to obtain adequate
radial as well as lateral margins. C The specimen is then oriented
accurately for the pathologist.
pathologist and all the rectal incisions are closed in either a
longitudinal or transverse manner to avoid narrowing of the
rectum, using an absorbable suture. An air test should be performed, filling the operative field with sterile saline, and insufflating air in the rectum in order to check for air leaks in the
suture line. Once these air leaks are controlled, the levator ani
Transcoccygeal Excision
The transcoccygeal approach was used historically over the
is reapproximated in the midline, and the anal coccygeal ligament is reattached to the sacrum. The operation is completed
with closure of the skin and subcutaneous tissue.
transanal approach for larger, more proximal lesions. It was
originally popularized by Kraske who found it beneficial
when operating on lesions within the middle or distal third of
the rectum. This approach is especially useful for lesions on
the posterior wall of the rectum, but can certainly be used for
anterior or lateral lesions as well. In our series, the transcoccygeal approach was used where the distal margin was
approximately 4.8 cm from the dentate line as compared with
3.0 cm for the transanal approach.
86
All patients should undergo a full antibiotic and mechanical bowel preparation the day before surgery. The patient is
again placed in the prone-jackknife position with the buttocks
taped apart after the induction of general anesthesia. The tape
will be released for closure to facilitate the approximation of
the subcutaneous tissues and skin. Unlike the transanal
approach, a pudendal block is not required, because the
sphincters do not require relaxation. The patient is prepped
and draped in a sterile manner with povidone-iodine solution,
and an incision is made in the posterior midline adjacent to
the sacrum and coccyx down to the upper border of the posterior aspect of the external sphincter. The coccyx, which
along with the anal coccygeal ligament lies immediately deep
to the skin and subcutaneous tissue, is removed to improve
exposure. To do so, the anal coccygeal ligaments and other
attachments are cauterized from each side and from the lower
edge of the coccyx. The dissection then proceeds along the
undersurface, anterior edge, of the coccyx until a cutting wire
can pass through the sacral coccygeal joint. The coccyx is
FIGURE 30-9. Transcoccygeal excision. For posterior lesions using a
transcoccygeal or “Kraske” approach, one can palpate the lower
border of the tumor to ensure an adequate distal margin.
30. Surgical Treatment of Rectal Cancer 427
Transanal Endoscopic Microsurgery
FIGURE 30-10. Transcoccygeal excision. Anterior lesions need to be
approached by first making a posterior proctotomy and then excising
the lesion through the rectum. The anterior and posterior walls of the
rectum then need to be repaired, usually in a transverse manner in
order to maintain the lumen diameter.
An unfortunate complication of this procedure is the
development of a fecal fistula that extends from the rectum to
the posterior midline incision. The incidence of this
complication ranges from 5% to 20%,
86–88
and most heal
after temporary diversion of the fecal stream via a loop
ileostomy or colostomy. For this reason, the Kraske approach
is used much less frequently than other methods for local
treatment.
Transsphincteric Excision
TEM was first described in 1984 by Gerhard Buess of
Tubingen, Germany.
89
The surgery is performed with the use
of a special resectoscope which is 4 cm in diameter and available in lengths of both 12 and 20 cm. The scope is inserted
with an obturator in place, which is then removed and
replaced with an air-tight glass faceplate. The rectum is then
manually insufflated, such as in rigid sigmoidoscopy, and the
lesion is identified and centered in the field. The scope is then
secured in position with the aid of a support arm that is
attached to the operating table. The glass faceplate is then
removed and replaced with a working adapter that contains
four instrument ports and a fifth port for the stereoscope
which is connected to a camera and projected onto a monitor.
Carbon dioxide is then insufflated at low pressure (10–15 cm
H
O) to distend the rectum and allow for visualization of
2
the lesion.
Once setup is complete, the operation proceeds in a manner
similar to a transanal excision using a variety of special endoscopic instruments, which are introduced through the four ports
in the working adapter. We begin with an injection of 1:100,000
solution of epinephrine in the submucosal plane around the
lesion to aid with hemostasis. The margin of resection is then
marked 1–1.5 cm circumferentially around the lesion using
electrocautery. The lesion is then grasped and the excision proceeds along the previously marked line through the full thickness of the rectal wall and into the perirectal fat. The specimen
is removed by temporarily removing the faceplate after complete excision. The defect is then closed using 3-0 long-lasting
absorbable suture in a continuous or interrupted manner.
TEM allows for local excision of proximal rectal lesions
that are not accessible via the transanal, transsphincteric, or
transcoccygeal approaches. Despite favorable results of this
relatively new technique, it has not gained widespread popularity secondary to the expense of the equipment, lack of
familiarity with the equipment and setup, and complexity of
the TEM operating system.
The transsphincteric approach developed by York and Mason
involves the complete division of the sphincters and the posterior wall of the rectum. The procedure starts similarly to the
Kraske transcoccygeal approach, except the levator ani and
the external sphincter muscles are divided in the midline.
These muscles are carefully tagged so that they can be reapproximated exactly at the end of the procedure. Care must be
taken to remain in the midline to avoid the nerve supply to the
sphincters that lie in a posterolateral position bilaterally. Once
the lesion is removed, the rectum, sphincters, and overlying
musculature are closed in a careful stepwise manner. This
procedure has an increased risk of incontinence secondary to
sphincter dysfunction. Because the exposure provided from
this approach is similar to that from the Kraske procedure,
which carries less of a risk of incontinence, there are very few
indications for this technique.
Outcomes: Retrospective Studies
The majority of the literature for local excision of rectal cancer comes from small retrospective reviews from single institutions. These studies are difficult to interpret because there is
no uniform approach among the reviews. The length of
follow-up varies from study to study, and many combine
patients with tumors of different depth, positive margins, and
different forms of local therapy including snare cautery and
fulguration.
These retrospective reviews report a local recurrence rate of
5%–33% and survival rates of 57%–100%
These studies demonstrate that patients with superficial
tumors and negative margins at the time of resection have low
recurrence rates and a very good prognosis. Although these
studies are not conclusive, they do suggest that local excision
90–94
(Table 30-2).
428 R. Bleday and J. Garcia-Aguilar
TABLE 30-2. Series of local excision alone (retrospective series)
Author No. of patients Treatment arms Follow-up Recurrence local Survival
Koscinski 58 (26 T1 and 32 T2) 47 TA, 6 TC, 5 TEM Mean of 48 mo for T1, 5% T1, 100%
Mellgren 261 (All T1 and T2) 108 LE via TA; 153 Mean of 52.8 mo T1 estimated, 18% T1, 72% (LE), 80%
93
et al.
Horn 38 (17 T1, 14 T2, 7 3 endoscopic Median of 50 mo T1, 0% T1, 100%
Gall 84 (54 T1, 19 T2, 11 T3) 16 endoscopic Median of 77.5 mo T1, 11% (LE), 0% T1, 74% ± 15% (LE),
121
et al.
Morson 143 (115 T1, 20 T2, 143 LE; only 91 with 2/91 (2%) with Corr. 5 y of 100%
82
et al.
Whiteway 46 (13 T1, 18 T2, 46 TA and TSp; 27 for Approximately 8 (17%) Cancer specific survival
Source: From Ref. 124.
LE, local excision; TA, transanal excision; TC, transcoccygeal excision; TSp, transsphincteric excision.
requiring APR polypectomy, 35 T2, 43% T2, 82.6%
after LE) TA, 5 salvage APR
via LE; 383 APR polypectomy, 68 LE, (APR) 100%–2% (APR)
7 T3) negative margins negative margins with negative margins
15 T3) cure, 6 disseminated of 87%
via APR (LE), 0% (APR) (APR)
383 APR T2, 22% (LE), 5% T2, 68% ± 24% (LE),
disease; 13 for high
risk
Stage I and 59 mo T2, 28% T2, 87.5%
for Stage II
T2 estimated, 47% T2, 65% (LE), 81%
(LE), 6% (APR) (APR)
(APR) 76% ± 11% (APR)
13/69 (19%) with Corr. 5 y of 83%–96%
positive margins with positive margins
may provide adequate oncologic control with considerably
lower morbidity and mortality rates than APR for select distal rectal cancers.
Local Excision and Adjuvant Therapy
Local recurrence continues to be a major source of morbidity
and mortality after both local excisions and radical resections
for rectal cancer. The major risk factors for recurrence include
the depth of invasion of the primary tumor, positive surgical
margins, histologic grade of the tumor, and the presence of
tumor in the regional lymph nodes. The addition of adjuvant
or neoadjuvant radiation has been shown to decrease these
local recurrence rates, and there is increasing evidence that
chemoradiation may have a beneficial effect on survival. One
of the major shortcomings of local excision is the inability to
pathologically assess the regional lymph nodes. Microscopic
disease can be present in the regional lymph nodes in up to
12% of T1 lesions, 22% of T2 lesions, and 58% of T3 and T4
95,96
lesions.
rence if left untreated. These findings have caused many
observers to advocate the use of postoperative radiation after
local excision in an attempt to eradicate any nodal disease,
especially in more aggressive tumors with some of the risk
factors previously mentioned. It also further emphasizes the
need for preoperative ERUS or eMRI to identify patients with
nodal disease who may be inappropriate for local excision.
Similar to the studies for local excision alone, many of the
studies involving local excision combined with pre- or
postoperative chemoradiation are small retrospective single-
This microscopic disease may lead to local recur-
institution studies, and thus are difficult to interpret (Table
30-3). The patient population, radiation and chemotherapy
protocols, and tumor characteristics are highly variable
among these studies. The survival rates for these studies range
from 33% to 100% depending on tumor stage and the use of
adjuvant therapy. However, local recurrence rates are
decreased when compared with local excision alone, ranging
from 0% to 15% for T1 and T2 lesions, and 0% to 20% for T3
lesions.
76,91,94,97–99
Prospective Studies
Unfortunately, there are very few prospective studies that use
local excision for distal rectal adenocarcinoma with or without chemoradiotherapy (Table 30-4). We treated 48 patients
with rectal adenocarcinoma via local excision, using postoperative chemoradiation for all T2 and T3 lesions. Over a mean
follow-up period of 40.5 months, we found an overall survival
of 93.8%, with recurrence rates by stage of 0% for T0 lesions,
9.5% for T1 lesions, 0% for T2 lesions, and 40% for T3
lesions. Of note, local recurrence was seen in three of five
patients with lymphatic invasion and two of two patients with
positive margins at the time of local excision.
results, we concluded that surgery alone was adequate for T1
lesions, whereas T2 lesions required a combination of surgery
and chemoradiation for adequate results, provided that there
were negative margins and no lymphatic involvement. If
either of these characteristics were present, we recommended
the addition of chemoradiation for T1 lesions, and radical
resection for T2 lesions.
86
From our
30. Surgical Treatment of Rectal Cancer 429
TABLE 30-3. Local excision plus XRT (retrospective series)
Author No. of patients Treatment arms Follow-up Local recurrence Survival
Wong 25 21 TA, 4 endoscopic Median 72 mo (minimum 6/25 (24%) Crude 5-y survival
19
et al.
Mendenhall 67 (34 T1, 12 T2, 2 T3) 65 TA, 2 TC Median 65 mo (6–273 mo) T1 = 11% T1 = 76%
99
et al.
Bailey 63 (35 T1, 18 T2, 10 T3) 63 LE Median 44 mo (12–130) 4/53 (7.5%) Crude 5-y survival
97
et al.
Chakravarti 99 (58 T1, 41 T2) 52 LE alone Median 51 mo (4–162 mo) LE alone = 11% T1, Relapse-free 5-y
91
et al.
Paty 125 (74 T1, 51 T2) 125 LE Median 80.4 mo T1 = 17% 10-y survival of 74%
94
et al.
Willett et al. 56 (34 T1, 22 T2) 45 TA or TSp, 10 TC, 1 Median 48 mo Since 1985, 0/20 Actuarial 5-y
98
et al.
Source: From Ref. 124.
LE, local excision; TA, transanal excision; TC, transcoccygeal excision; TSp, transsphincteric excision; Gy, gray; CRT, chemoradiation therapy; XRT, radiation therapy.
polypectomy or fulguration, of 36 mo) 96%
all got 50 Gy XRT postop
48 received 45–60 Gy T2–3 = 25% T2–3 = 77%
XRT postop
34 XRT, 45–50 Gy 74.3%
67% T2 survival
47 LE plus 45–64.8 GY LE + CRT = 0% LE alone = 80% T1,
XRT (45 postop, 2 preop) T1, 15% T2 33% T2
33 also had 5-FU LE + CRT = 65% T1,
76% T2
for T1 and 72%
for T2
31 received 45–54 Gy and
15 of them got 5-FU T2 = 26%
fulguration, 30 received patients after recurrent-free
45 Gy postop XRT. Since chemoradiation survival of 72%
1986, received 5-FU
100
Ota
published results on a study of 46 patients with a
median follow-up time of 36 months. In this study, all patients
received postoperative radiation, whereas T3 patients also
received chemotherapy in addition to their radiation treatments. He reported a 6.5% local recurrence rate and a 3-year
survival rate of 93%.
Steele et al. published a multicenter, prospective trial of
local excision for rectal cancer in 110 patients.
81
All of these
patients were thoroughly screened preoperatively to ensure
that their tumors were within 10 cm of the dentate line, <4 cm
in size, and involved < 40% of the circumference of the bowel
wall. Furthermore, all patients had to be N0M0, and statistical analyses were only performed on patients with negative
margins at the time of resection. Patients were treated with
postoperative chemoradiation only if they had T2 lesions.
They published survival rates of 87% and 85% for T1 and T2
lesions, respectively, with an overall survival rate of 85%.
They also found an overall disease-free survival rate of 78%,
with 84% for T1 lesions, and 71% for T2 lesions. These data
compare very favorably with APR, with a 5-year survival rate
of 70% for Stage I disease. Unfortunately, the retrospective
APR data are not separated into T1 and T2 lesions, making
comparison difficult.
Transanal Endoscopic Microsurgery
Because TEM is still a relatively new technique, the data supporting its use are still being compiled. There are a few small,
single-institution, retrospective, and prospective studies
describing the use and outcomes of TEM for the excision of
rectal cancer.
recurrence rates ranging from 83% to 100% and 0% to 27%,
101–103
In general, these studies show survival and
TABLE 30-4. Local excision plus adjuvant therapy (prospective series)
Author No. of patients Treatment arms Follow-up Local recurrence Survival
100
Ota
Bleday 48 (21 T1, 21 T2, 6 T3) Postop XRT 54 Gy and 5-FU
et al.
Steele 110 (59 T1, 51 T2) Postop XRT 54 Gy and 5-FU/
et al.
Source: From Ref. 124.
46 LE Median 36 mo 3/46 (6.5%) Overall 3-y survival 93%
86
81
Postop XRT (53 Gy) (18–73) All T3’s
5-FU for 7 T3’s, 1 T2
/500 mg/M2day 1–3, 28–30
for T2, T3 lesions Mean 40.5 mo 4/48 (8%) Overall 3-y survival 93.8%
500 mg/M2day 1–3, 29–31
for T2 lesions Mean 48 mo T1, 3/59 (5.1%) Overall 6-y survival 85%
T2, 7/51 (13.7%)
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