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24 Colorectal Neoplasms: Screening andSurveillance After Polypectomy
335
only 59% of Americans over the age of 50
were screened according to current guidelines.
Furthermore, there appears to be wide geographic variability in screening patterns.
• Prior to making a recommendation regarding
surveillance colonoscopy, the endoscopist
should carefully consider the personal and family history of colorectal neoplasia, potential
technical issues with colonoscopy and associated risk, and life expectancy of the patient.
Surveillance
• It is important to note that the current guidelines for surveillance are to be applied only
Guidelines forSurveillance After
Polypectomy
after high-quality baseline colonoscopy with
complete removal of all detected lesions. If
either of these two criteria is not met, then
History
• Consensus guidelines have evolved from the
recommendation for annual repeat colonoscopy following polypectomy in the 1970s to
recommendations based on the number, size,
location, and histologic features of the polyps
removed (Table24.2).
Table 24.2 Recommendations for screening intervals based on consensus guidelines for patients with serrated polyps
based on histology, number, location, and size
Histology Size Number Location Interval in years
HP <10mm Any number+ Rectosigmoid 10+++
HP
HP Any
HP > 5mm
SSA/P or TSA <10mm <3 Any 5
SSA/P or TSA
SSA/P or TSA <10mm
SSA/P
SSA/P/w/dysplasia Any Any 1–3++++
With permission from Rex DK, Ahnen DJ, Baron JA, Batts KP, Burke CA, Burt RW, etal. Serrated lesions of the colorectum: review and recommendations from an expert panel. Am J Gastroenterol. 2012;107(9):1315–29; quiz 4, 3
Reproduced with permission. © Nature Publishing Group
Note 1: Patients with both signicant serrated ndings and concurrent adenomas may be at a more advanced stage in
the progression toward cancer. Closer follow-up may be indicated in some cases based on clinical judgment
Note 2: In general, these recommendations for surveillance are for the rst follow-up. For ndings with short follow-up
recommendations, a longer subsequent follow-up interval may be appropriately applied when a follow-up exam shows
improvement in ndings, i.e., reduction in the number, size, and/or histologic severity of lesions
Note 3: Because of interobserver variation in the pathologic differentiation of HP from SSA/P, proximal colon serrated
lesions >10mm in size that are designated HP may be considered to be SSA/P by clinicians
SSA sessile serrated adenoma, TSA traditional serrated adenoma
+The interval recommendations presented here represent consensus opinion based on low-quality or very low-quality
evidence. They are likely to change as higher-quality evidence becomes available, and alternatives may be equally
reasonable
+Patients with >20HPs in the rectosigmoid meet the World Health Organization denition of serrated polyposis if there
are additional serrated lesions proximal to the sigmoid
++Some panel members follow a policy of 5years if there are multiple HPs 6–9mm in size in the rectosigmoid
+++Patients with two or more serrated polyps ≥10mm in the proximal colon meet the World Health Organization
criteria for serrated polyps if three additional serrated lesions of any size proximal to the sigmoid are identied
++++SSA/P with cytological dysplasia is a more advanced lesion than SSA/P.Depending on the size of the lesion, the
condence in complete endoscopic resection and other associated lesions, intervals shorter than 3 years may be
appropriate
≤5mm ≤3
≥4
≥1
≥10mm
≥10mm ≤2
1 Any 3
≥3
repeat examination should be planned.
• Discontinuation of surveillance should be
considered in patients with less than a 10-year
life expectancy.
• These guidelines apply only to asymptomatic
individuals; new symptoms should prompt
consideration of diagnostic work-up.
Proximal to sigmoid 10
Proximal to sigmoid 5
Proximal to sigmoid 5
Any 3
Any 1–3+++
336
ab
E. H. Carchman and C. P. Heise
Surveillance Based onPathology
ofPolyp
Hyperplastic andSerrated Polyps
• Serrated lesions of the colon and rectum are
classied by the World Health Organization
(WHO) into three general categories based on
cytological features, architectural features,
and location. The categories include hyperplastic polyps, sessile serrated adenoma/polyps, and traditional serrated adenomas
(Fig.24.2a, b).
• Small hyperplastic polyps in the rectosigmoid
are very common and are not believed to be
associated with development of adenomatous
colorectal neoplasia. If encountered, they
should be biopsied to establish a diagnosis,
but otherwise their presence does not alter the
patient’s risk stratication.
• Sessile serrated adenomas/polyps are usually
located in the proximal colon, sessile or at in
morphology, pale in color, with indistinct borders, and usually have a mucus cap. Due to
their indistinct appearance, there is a high rate
of incomplete resection. NBI and chromoendoscopy techniques can be used to facilitate
identication and delineation of borders.
Given that incomplete resection rates are high
for serrated adenomas greater than 1cm, some
authors have recommended routine tattooing
of the polypectomy site to facilitate identication at repeat colonoscopy.
• There is increasing awareness that these
lesions may be precursor lesions to cancer
development in about 1/3 of colorectal cancer
cases. Recent reviews on the management of
serrated lesions recommended complete
removal of all lesions except for ≤5mm in
sigmoid or rectum.
Adenoma
• Adenomas can be classied histologically as
tubular, villous, or tubulovillous. According to
the World Health Organization criteria, tubular adenomas have less than 25% villous component, tubulovillous 25–75%, and villous
greater than 75%.
• Tubular adenomas are the most common type of
adenoma found followed by tubulovillous and
then villous. Tubular adenomas have <5% of
harboring cancer, while the risk of tubulovillous
is 20–25%, and villous adenomas is 35–40%.
• Screening series have reported an adenoma
prevalence rate of 15–30%. With the addition
of high-denition colonoscopy, this number
has been quoted as high as 50%.
Fig. 24.2 Endoscopic views of two different types of serrated polyps. (a) Sessile serrated adenoma/polyp in cecum and
(b) a traditional serrated adenoma of rectum
24 Colorectal Neoplasms: Screening andSurveillance After Polypectomy
be done yearly until no polyps are found.
Thereafter, patients with juvenile polyps
should undergo surveillance colonoscopy
every 3years as long as no further polyps are
detected.
• Patients who meet clinical criteria for PeutzJeghers syndrome should undergo genetic
testing for a germline mutation. In terms of
surveillance, these patients should undergo a
colonoscopy every 2–3years starting in late
adolescence. They should also have upper
endoscopies every 2–3 years. Small bowel
interrogation (CT enterography) should also
occur every 2–3years.
• Please see Chap. 23, Molecular Basis of
Colorectal Cancer and Overview of Inherited
Colorectal Cancer Syndromes, for a detailed
Fig. 24.3 Endoscopic view of a cecal ulceration which
pathology after biopsy demonstrated colonic mucosa with
adenomatous change and focal high-grade dysplasia
description of these entities.
Inammatory Bowel Disease
• In patients with inammatory bowel disease
• The recommendations for post-polypectomy
surveillance are outlined in Table24.2.
• Those patients with sessile adenomas that
were removed in piecemeal fashion should be
reexamined in 2–6 months to conrm complete lack of regrowth (Fig.24.3).
• Patients with >10 adenomas at one examination should have follow-up in less than 3years
and should be considered for referral to a
genetic counselor.
(IBD), the presence of chronic inammation
puts them at an increased risk for dysplasia
and cancer.
• Polyps detected in patients with IBD are
referred to as a dysplasia-associated lesion or
mass (DALM).
– DALM lesions are then divided into three
categories based on endoscopic appearance
and location:
1. It is a sporadic adenoma if the polyp
resembles an adenoma both endoscopi-
Inammatory Polyps
• Inammatory polyps include benign lymphoid polyps and pseudopolyps (such as those
seen in ulcerative colitis). Benign lymphoid
polyps are composed of normal lymphoid tissue and therefore do not require any surveillance if this is seen on pathology. Pseudopolyps
are discussed below in the inammatory disease section.
cally and histologically and is located
outside an area of histologically proven
colitis. Complete polypectomy with
routine surveillance is adequate with
these lesions.
2. It is an IBD-associated adenoma-like
polypoid dysplasia if the lesion
resembles an adenoma endoscopically
and histologically and is located in an
area of colitis. For these lesions, if they
Hamartomas Polyps
• Hamartomas of the colon and rectum include
juvenile polyps and polyps seen in PeutzJeghers syndrome.
• In a patient with juvenile polyps, all polyps
should be removed, and surveillance should
are not associated with at dysplasia or
carcinoma, polypectomy with surveillance at a shortened interval is
recommended.
3. Finally IBD-associated non-adenomalike dysplasia, which is considered a true
337
338
ab
E. H. Carchman and C. P. Heise
Fig. 24.4 (a) Endoscopic view of a polyp in the sigmoid
colon of a patient with ulcerative colitis. (b) The use of
chromoendoscopy in 4-2 allows for better visualization of
DALM, is a lesion that is irregular and
broadly based and is located in an area
of colitis. These lesions are at high risk
for associated carcinoma and should be
treated with colectomy after the diagnosis of dysplasia is conrmed by an experienced pathologist (Fig.24.4a, b).
the borders of the polyp compared to the images with
indigo carmine in 4A
Early Cancer (T1) Within Polyp
• There are two classication systems that are
established for the identication of cancer
within a polyp. The rst is Haggitt classication, which is utilized for quantifying the extent
of invasion in pedunculated polyps. The second
is the Kikuchi classication for sessile polyps.
• Haggitt classication for cancer in pedunculated polyps:
Surveillance withCancer Resection
– Haggitt level 0: Noninvasive.
– Haggitt level 1: Cancer invading into the
• Patients who undergo curative resection for
sporadic colorectal cancer are recommended
to undergo surveillance colonoscopy 1 year
after resection to look for metachronous neoplasia. If the examination at 1year is normal,
then the interval should be extended to 3years.
If that subsequent colonoscopy is normal, then
the interval is again increased to 5years.
• For those patients who undergo curative resection of rectal cancer, additional digital rectal
examination and proctoscopy should be performed every 3–6 months for the rst
2–3years and yearly for the next 2–3years to
look for signs of pelvic recurrence.
submucosa but limited to the head of the
polyp.
– Haggitt level 2: Cancer invades into the
neck of the polyp.
– Haggitt level 3: Cancer invading the stalk
of the polyp.
– Haggitt level 4: Cancer invading the sub-
mucosa of the bowel wall below the stalk.
• The risk of spread to the lymph nodes is less
than 1% for levels 1–3, and if the polypectomy margin is negative, observation can be
considered. For Haggitt level 4, the risk of
nodal metastases ranges from 12% to 25%,
and colectomy should be strongly considered.
24 Colorectal Neoplasms: Screening andSurveillance After Polypectomy
ab
339
Fig. 24.5 (a) A 2cm rectal polyp noted endoscopically.
(b) Polyp was resected and tattooed based on size criteria.
Final pathology demonstrated moderately differentiated
• Kikuchi classication of cancer in polyps.
Invasion of the submucosa is divided into three:
– SM1 is invasion of the upper one-third.
– SM2 is invasion of the middle third.
– SM3 is invasion into the lower one-third.
• Haggitt levels 1–3 are equivalent to SM1, and
Haggitt level 4 can be SM1, SM2, or SM3.
There have been several factors identied that
increase the risk of lymph node metastases.
These factors include lymphovascular invasion, poor differentiation, gender, extensive
budding, and SM3 invasion.
• For low-risk cancers, Haggitt levels 1–3,
Kikuchi SM1, or no evidence of poor differentiation or angioinvasion, where the lesion has
been completely resected in one piece with
negative margins, endoscopic or local excision is regarded as adequate treatment.
• However, patients should be made aware that
although the risk of nodal metastases is very
low, it is not zero and that there is no effective
surveillance that will reliably detect nodal
metastases prior to distant metastatic spread.
• Although surveillance colonoscopy is recommended at frequent intervals (e.g., yearly), the
risk of tumor growth after resection of pedunculated polyps with a focus of cancer is in the
invasive colonic adenocarcinoma with mucinous features
arising from tubulovillous adenoma. Carcinoma present at
cauterized margins
nodes, not in the lumen, calling into question
the value of frequent colonoscopy.
• Surveillance is usually continued for 5years.
There has been some debate on this matter;
however, in that there are studies that demonstrate that the risk for recurrence extends past
5years post-polypectomy.
• Formal surgical resection is indicated for highrisk cancers (Haggitt level 4, Kikuchi SM3,
lymphovascular invasion, poor differentiation,
or positive resection margin, cancer in sessile
lesions removed in piecemeal fashion).
When toTattoo anArea After
Polypectomy
• Current guidelines strongly recommend tattooing of suspicious lesions during colonoscopy.
Given that risk of cancer arising from a polyp
in the National Bowel Cancer Screening
Program increased signicantly when the
polyp was greater than 1 cm in size, most
would recommend tattoo of all polyps greater
than 1cm (Fig.24.5a, b).
• In addition, when sessile lesions are removed
in piecemeal fashion, the risk of recurrence is
340
E. H. Carchman and C. P. Heise
high. Tattoo at the site of polypectomy should
be considered to help identify the area at subsequent colonoscopy.
Benets ofSurveillance
• There have been several studies that have
examined the benets of post-polypectomy
surveillance in terms of cancer prevention.
These studies identied the risk of colorectal
cancer after adenoma resection that depended
not only upon the characteristics of the adenoma (advanced or non-advanced) but also
colonoscopy surveillance practices. None of
these studies are randomized, controlled trials,
so there is no direct evidence on the exact benet that is obtained through surveillance.
Status ofSurveillance
• Surveys demonstrated that 50% of endoscopists are not following the guidelines for postpolypectomy surveillance, often performing
surveillance examinations more frequently
than recommended. Some authors have suggested that failure to follow guidelines was
due to uncertainty, fear of malpractice, and
nancial gain.
both adenoma and carcinoma formation.
These agents have included nonsteroidal antiinammatory agents, folic acid, calcium, and
various antioxidants.
• A systematic review identied several randomized, controlled trials evaluating for the
potential benets of these agents. They concluded that the use of aspirin (81–325mg/day)
in individuals with a history of adenomas or
colorectal cancer (CRC) resulted in a 21%
reduction in adenoma recurrence. Though not
evident until after a prolonged follow-up
period (23 years), a 26% reduction in CRC
incidence was noted in the general population
in studies evaluating a larger aspirin dose
(300–1500mg/day).
• Non-aspirin anti-inammatory medications
such as celecoxib (400 mg/day) have also
demonstrated benet in patients with a history
of adenomas, revealing a 34% reduction in
adenoma recurrence.
• Though the use of folic acid failed to show
benet with respect to adenoma recurrence,
calcium intake (1200–2000 mg/day) was
found benecial with an 18% risk reduction
after a history of prior adenomas.
• There was no signicant benet with regard to
adenoma recurrence noted with antioxidant
ingestion (vitamins A, C, E, beta-carotene, or
selenium).
Chemoprevention
• A variety of oral agents have been evaluated
as possible chemopreventive strategies for
Colon Cancer: Preoperative
Evaluation andStaging
CaryB.Aarons andNajjiaN.Mahmoud
25
Key Concepts
• Total colonic evaluation is recommended prior
to surgical intervention to exclude synchronous tumors that may alter surgical plan.
• Evaluation for metastatic disease by crosssectional imaging is recommended prior to
surgical intervention, as it may alter treatment
decisions.
• Preoperative carcinoembryonic antigen
(CEA) level should be obtained, as changes in
CEA may herald tumor recurrence.
• Tumor location should be identied
preoperatively.
• Tumor grade, lymphovascular invasion, margin status, and immunohistochemical assessment of mismatch repair proteins may have
prognostic signicance and should be routinely reported.
Background
• Once the diagnosis of colon cancer is made,
the goal of preoperative evaluation is to
C. B. Aarons
Division of Colon and Rectal Surgery, Hospital of the
University of Pennsylvania, Philadelphia, PA, USA
N. N. Mahmoud (*)
Division of Colon and Rectal Surgery, Department of
Surgery, University of Pennsylvania Health System,
Philadelphia, PA, USA
e-mail: najjia.mahmoud@uphs.upenn.edu
establish the location of the tumor, assess for
metastatic disease and adjacent organ invasion, and identify other patient and tumor factors that may affect outcome or alter the
medical or surgical approach to treatment.
• The primary importance of staging in colon
cancer is to rule out additional pathology and
distant metastatic disease (stage IV), which
can affect treatment approach. This differs
from rectal cancer where estimates of locoregional tumor stage have a greater effect on
treatment planning.
Clinical Presentation
• Colon cancer presents in three common ways:
– Asymptomatic: lesion detected during rou-
tine screening examination
– Non-specic subacute symptoms and signs
that should prompt further investigation
such as change in bowel habits, chronic
abdominal pain, rectal bleeding, anorectal
discomfort, iron-deciency anemia, lethargy, weight loss, and fatigue
– Emergent: perforation or obstruction
• Symptoms will often manifest differently
depending on tumor location and size.
• Late ndings can include palpable abdominal mass, severe weight loss, intestinal
obstruction, and, in rare cases, perforation
leading to peritonitis or stulization to adjacent organs.
© ASCRS (American Society of Colon and Rectal Surgeons) 2019
S. R. Steele et al. (eds.), The ASCRS Manual of Colon and Rectal Surgery,
https://doi.org/10.1007/978-3-030-01165-9_25
341
342
C. B. Aarons and N. N. Mahmoud
• Approximately 20–25% of colon cancer will
present with metastatic disease at the time of
diagnosis; therefore, it is also critical to evaluate patients for signs and symptoms associated with metastatic disease. Widely metastatic
cancers can result in constitutional symptoms
such as unintentional weight loss, cachexia,
weakness, and anorexia.
Preoperative Evaluation
• History: duration and severity of symptoms
associated with the primary tumor such as
intestinal obstructive symptoms, anemia, and
abdominal pain, as well as those associated
with metastatic disease such as weight loss
and fatigue. History of inammatory bowel
disease.
• Family history: history of colorectal cancer or
other cancers known to be associated with
inherited colon cancer syndromes.
• Overall health: assess readiness for any surgical intervention.
• Physical examination: palpable mass, distant
adenopathy, tenderness, or distention.
Tumor Localization
• Pitfalls
– Colonoscopy is often inaccurate with
regard to anatomic localization. Review of
colon endoscopic photographs may be
helpful, as anatomic landmarks (e.g., ileocecal valve) may sometimes be identied
in the same image as the tumor.
– For distal lesions, it should be remembered
that estimates of distance to the anal verge
are often highly inaccurate when measured
with a exible endoscope and may have
little relationship to the true anatomy.
• Endoscopic localization
– Tattoo placed adjacent to the lesion in mul-
tiple quadrants, typically just distal to the
tumor, may assist in operative localization.
Although visceral obesity may limit the
ability to see tattoo intraoperatively, the
tattoo is still valuable, as it can be identied
by intraoperative colonoscopy.
– If cancer was detected in a polyp that was
removed endoscopically, and the site not
tattooed at index colonoscopy, then expeditious repeat colonoscopy with tattooing
of the polypectomy scar should be considered. This is usually most effective
when performed by the original
endoscopist.
– Endoscopic clips may be placed at the time
of polypectomy/biopsy, and plain abdominal radiographs obtained immediately
post-colonoscopy. The colon will usually
still be lled with gas and thus anatomic
relationships appreciated. Occasionally
clips will remain in situ long enough to be
detected on cross-sectional imaging that is
typically ordered after diagnosis is conrmed histologically.
– For distal lesions, repeat endoscopic evalu-
ation by the surgeon is critical. At minimum, all patients with left-sided lesions
should undergo preoperative proctoscopy
to ensure that the tumor is not in the
rectum.
– Intraoperative colonoscopy can localize a
small tumor. This can be performed immediately prior to operation or after exploration of the abdomen. The use of carbon
dioxide as an insufation gas is preferred,
in order to limit bowel dilatation. When
positioning the patient at operation, access
to the anus for intraoperative colonoscopy
should be considered.
• Radiographic localization
– Endoscopic clips (see above).
– Larger tumors may be localized via cross-
sectional imaging (CT, MR).
Total Colon Evaluation
• Total colon evaluation is critical to identify
synchronous neoplasms that may alter the
planned operation. The rate of synchronous
cancers is understood to be about 5%; and the
overall rate of synchronous neoplasia that
25 Colon Cancer: Preoperative Evaluation andStaging
343
would change operative approach is somewhat higher.
• If preoperative colonoscopy is not possible,
CT colonography or contrast enema may be
performed.
• Occasionally, high partial obstruction from
the tumor will limit preoperative proximal
colonic evaluation via endoscopy or contrast
radiography, but the patient will be able to tolerate preoperative bowel preparation. In these
cases, intraoperative colonoscopy performed
via the colon proximal to the tumor may be
considered.
• For cases of obstructing cancers that preclude
adequate endoscopic or radiographic assessment preoperatively, intraoperative colonic
lavage and colonoscopy should be considered.
If this is not possible, the proximal colon
should be palpated intraoperatively, and if no
obvious lesions detected, a full colonoscopy
should be performed when safe to do so after
surgery.
Carcinoembryonic Antigen (CEA)
associated with poorer survival and increased
recurrence in several studies; however, contradictory studies do exist. Therefore, there is
currently insufcient evidence to support the
use of elevated preoperative serum CEA levels
as an absolute indication for adjuvant
chemotherapy.
• Current American Society of Clinical
Oncology (ASCO) guidelines recommend
that serum CEA levels be obtained preoperatively in patients with demonstrated colorectal
cancer for posttreatment follow-up and assessment of prognosis.
• Elevated preoperative CEA levels that do not
normalize following surgical resection imply
the presence of persistent disease.
• Furthermore, serial testing of CEA levels
should be performed for 5years for patients
with stage II and III disease in those eligible
for surgery or chemotherapy if metastatic disease is discovered. Rising CEA levels after
surgical resection implies recurrent disease
and should prompt consideration of radiologic
and endoscopic evaluation to look for treatable disease.
• CEA is a glycoprotein primarily involved in
intercellular adhesion that is produced by
columnar and goblet cells and can be found in
normal colonic mucosa. It is found in low levels in the circulation of healthy individuals,
but it is overexpressed in a variety of cancers,
including colorectal cancer.
• Elevated serum levels may be identied in
heavy smokers, in benign conditions such as
pancreatitis and inammatory bowel disease,
as well as in malignancies outside of the gastrointestinal tract; therefore, CEA is not a sensitive or specic screening tool for colorectal
cancer.
• CEA is an important tool in CRC surveillance
after surgical resection since its elevation may
be the rst indication of locally recurrent or
metastatic disease.
• Patients with preoperative serum CEA >5ng/
mL have a worse prognosis, stage for stage,
than those with lower levels. Elevated preoperative CEA levels have been shown to be
Radiographic Evaluation
• Preoperative radiographic imaging is useful
for initial staging of newly diagnosed or recurrent colon cancers.
• Computed tomography (CT) scans of the
chest, abdomen, and pelvis with intravenous
contrast provide valuable preoperative information about distant metastases, tumor
localization, and possible invasion of adjacent
organs.
– CT scan has a sensitivity ranging from 75%
to 90% for detecting distant metastasis;
however, the ability to accurately detect
nodal involvement or small peritoneal
metastases is poor.
– The routine use of CT for imaging of the
chest remains controversial for initial
staging of colon cancer, as compared to
rectal cancers. In asymptomatic patients
in whom the suspicion of lung metastasis
344
C. B. Aarons and N. N. Mahmoud
is low, a plain chest x-ray will sufce. Any
suspicious ndings on chest x-ray can be
investigated with a noncontrast chest CT
scan.
• Contrast-enhanced magnetic resonance imaging (MRI) is particularly valuable in evaluating smaller suspicious liver lesions (especially
in the presence of fatty liver changes) with
sensitivities up to 97%. In routine clinical
practice, MRI should be reserved for the evaluation of suspicious liver lesions not clearly
characterized on CT scan or for operative
planning prior to liver metastectomy.
• Positron emission tomography–computed
tomography (PET/CT) scan is useful for characterization of indeterminate possibly metastatic lesions and should be routinely
employed prior to embarking on radical resection of locally recurrent or metastatic disease.
– PET is less sensitive in the detection of
mucinous tumors, given the relatively
lower cell/tumor mass ratio.
Preoperative Evaluation
ofCoexisting Medical Conditions
cross-sectional imaging and are not recommended routinely.
• Nutritional panels are not generally required
unless there are signicant concerns for underlying malnutrition. Complete optimization of
nutritional parameters, either parenterally or
enterally, typically takes weeks, which would
delay surgery unnecessarily.
• Smoking cessation should be emphasized but
should not delay surgery, as any substantial
benets would not be realized for several
weeks. However, there may be measurable
gains in improving postoperative wound healing and reducing postoperative pulmonary
complications if patients can stop smoking
preoperatively.
• In patients with renal insufciency, care must
be taken with choosing preoperative bowel
preparation, and special attention must be paid
to perioperative uid balances. Additionally,
diuretics, angiotensin-converting enzyme
inhibitors, and angiotensin receptor blockers
should be held the day prior to surgery to minimize the risk of profound hypotension during
surgery.
• Regardless of the operative approach, colorectal procedures carry inherent risks, which can
be divided into procedure-specic risks and
cardiopulmonary risks. Therefore, a thorough
history and physical examination encompassing the patient’s comorbidities is also vital.
This is immensely important because surgical
morbidity and mortality can be greatly
improved by a careful assessment of organspecic risks and, if feasible, preoperative
optimization.
• A detailed knowledge of the patient’s prior
abdominal surgery will aid in the appropriate
operative planning.
• Routine preoperative testing should be
obtained and should include a complete blood
count (CBC), a metabolic panel, type and
screen, and a 12-lead electrocardiogram in
older patients with cardiac risk factors.
• Liver function tests are much less sensitive
for liver metastases as compared to
Staging ofColon Cancer
• The preferred staging system for colon and
rectal cancers is the TNM staging system put
forth by the American Joint Committee on
Cancer and the International Union Against
Cancer (UICC). This system, which is summarized in Table 25.1, consists of three
categories: tumor depth of invasion, nodal
involvement, and distant metastasis.
• Tumor stage is the most powerful driver of
prognosis and can help guide decisions regarding adjuvant therapy.
• The completeness of resection should also be
noted:
• R0—complete tumor resection with negative
margins
• R1—incomplete tumor resection with microscopic involvement of the margin
• R2—incomplete tumor resection with gross
residual disease that was not resected