COLON AND RECTAL CANCER
Selections from the 68th Annual Colon and Rectal Surgery: Conundrums and Controversies, presented September
2005 by the University of Minnesota Medical School
| COLORECTAL CANCER SCREENING: THE CASE FOR CONVENTIONAL COLONOSCOPY —John H. Bond, MD,
Professor of Medicine, University of Minnesota Medical School, Minneapolis; Chief, Gastroenterology Section, Minneapolis
Veterans Affairs Medical Center
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| National Polyp Study: 1418 patients followed for 8400 person-years; all patients had ≥1 adenomatous polyp at study entry
and underwent colonoscopy and resection of new polyps every 3 yr; only 5 new colorectal cancers reported, compared to 48
and 43 in 2 reference populations in which polyps not resected; removing polyps decreased subsequent incidence of cancer by
90%
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| Advanced adenomas: less common than small tubular adenomas (very common lesions that rarely advance to cancer);
defined as adenomatous polyps ≥1 cm, or containing villous tissue or high-grade dysplasia; more likely to progress to cancer
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| Screening: major guidelines state that all asymptomatic patients ≥50 yr of age with average risk should be offered colorectal
cancer screening; options—annual fecal occult blood test (FOBT); flexible sigmoidoscopy every 5 yr; FOBT
plus flexible sigmoidoscopy; double-contrast barium enema (DCBE) every 5 yr; colonoscopy every 10 yr
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| Limitations of indirect screening tests: FOBT—low specificity (many false positives); low sensitivity for advanced
adenomas; frequent screening necessary; flexible sigmoidoscopy—miss ≈30% of advanced neoplasia (located
in right colon); poorly tolerated; FOBT plus flexible sigmoidoscopy—complex; frequent screening necessary;
DCBE—low sensitivity and specificity; no study data
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| Advantages of colonoscopy: most effective method for detecting early cancers and advanced adenomas; diagnostic and
therapeutic; acceptable safety record when performed by experienced examiners; infrequent screening possible; cost-effective
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| Colonoscopy for detecting advanced neoplasia:
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 | Sensitivity for polyps ≥1 cm: Rex and Hixson studies—patients had back-to-back colonoscopies performed by 2 examiners;
sensitivity in Rex study 94%, in Hixson study 100%; Pickhardt study—colonoscopy compared to computed tomography
(CT) colonography (virtual colonoscopy); colonoscopy sensitivity 88%
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| Sensitivity for colorectal cancers: Rex study—sensitivity 95%; when examination performed by gastroenterologist, sensitivity
98%
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| Colonoscopy screening in United States: recommended as option by all screening guidelines since 1997; proposed
as preferred method by American College of Gastroenterology in 2000; reimbursement by Medicare for patients >65 yr
of age began in 2001; effectiveness—no randomized controlled studies; some case-control studies of flexible sigmoidoscopy
and colonoscopy indicate efficacy; colonoscopies precipitated by results of controlled randomized trials of FOBT
showed efficacy in decreasing colorectal cancer incidence and mortality
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| Limitations of colonoscopy: Nelson et al—3196 asymptomatic average-risk volunteers 50 to 75 yr of age underwent
colonoscopy in 13 Veterans Affairs (VA) centers; colonoscopy very effective (complete in 97.7%); no perforations (54% of
patients had polypectomy); overall major complication rate 0.3% (mostly bleeding after polypectomy); only 1 major complication
in 1492 patients who had diagnostic study only
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| Prevalence of advanced neoplasia: VA colonoscopy screening trial—in asymptomatic average-risk patients
(mostly men) 50 to 75 yr of age, prevalence of advanced neoplasia 10.5%; 52% of patients with proximal lesions had no
distal neoplasia (would have been missed by flexible sigmoidoscopy); COlorectal Neoplasia screening with Colonoscopy
in average-risk women at Regional Naval medical centers (CONCeRN) trial—in 1322 women, prevalence of
advanced neoplasia 4.8%; 69% of patients with proximal lesions had no distal neoplasia
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| Capacity: Seefe et al—direct colonoscopy of all patients >50 yr of age using 50% available capacity would take 10 yr;
colonoscopy capacity seriously limited, and other screening strategies needed
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| Barriers to direct colonoscopy screening: expensive, invasive, uncomfortable procedure that detects advanced
neoplasia in 6% to 10% of patients; risk small but can be serious, eg, perforations; preparation, procedure, and recovery
time take ≤2 days; patients must be accompanied by responsible adult when receiving IV conscious sedation; patients
averse to preparation and clear-liquid diet
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| MANAGING UPPER GI POLYPS IN FAP —Martin L. Freeman, MD, Professor of Medicine, University of Minnesota
Medical School; Director, Advanced Pancreaticobiliary Endoscopy Fellowship, University of Minnesota/Hennepin County
Medical Center, Minneapolis
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| Gastric fundic gland polyps (FGP): common in patients with familial adenomatous polyposis (FAP); prevalence
≈50%; rarely adenomatous or have malignant potential; aggressive therapy generally not indicated
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| Gastric adenomas: typically found in antrum; larger but less common than FGP; may be premalignant; therapy indicated
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| Duodenal adenomas: prevalence ≤90%; often multiple; typically ampulla (D2>D3>D4); therapy generally indicated;
can present as sporadic, multiple, or carpet of lesions (difficult to manage); best visualized with duodenoscopy
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| Ampullary adenomas: prevalence 50%; may appear normal; can have tubular, villous, or variable dysplasia; often asymptomatic,
but may present with pancreatitis or cholestasis; can appear as subtle, polypoid, or sessile lesions; upper gastrointestinal
(GI) cancer risk ≤12% by 6th decade; leading cause of death in FAP
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| Jejunal adenomas: cancer risk increasing with prevalence
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| Surveillance: esophagogastroduodenoscopy (EGD) with duodenoscope—in stomach, sample fundic gland polyps; in
duodenum, remove or ablate polyps >5 mm; in papilla, biopsy if symptoms or large or abnormal polyps present;
intervals—screen every 3 yr, beginning at 21 yr of age; jejunal surveillance—capsule endoscopy used increasingly;
speaker usually performs push endoscopy; pediatric colonoscope used to examine duodenum
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| Treatment: therapy indicated if symptoms, large lesions, advanced dysplasia, or adenomatous polyps present; complete surveillance
important before beginning therapy of any local lesion
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| Resection of ampullary neoplasms: papillectomy—preferred approach in most cases; endoscopic papillectomy can
be used to treat synchronous duodenal lesions; local excision—no advantage over endoscopic resection; cannot treat other
duodenal adenomas; higher morbidity and same recurrence as endoscopic resection; no longer performed; pancreaticoduodenectomy
(Whipple)—preferred for very large tumors, tumors invading ducts, tumors refractory to endoscopic
therapy, tumors with multiple dysplastic duodenal adenomas, or suspected cancer
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| Endoscopic papillectomy: candidates—lesions <4 cm; benign appearance, ie, no ulceration, soft; benign histologic
evaluation; no extension into bile duct; staging—typically involves CT and endoscopic ultrasonography (EUS); EUS
aids in sizing adenoma and revealing invasion into muscularis or pancreas; techniques—simple snare excision; pancreatic
and biliary sphincterotomy; saline lift injection; piecemeal excision; thermal ablation; pancreatic stent; speaker’s
main goal to access and drain pancreas; complications—traditionally, pancreatitis most worrisome, but pancreatic
stents have negated risk; hemorrhage treated with endoscopic clips; speaker most concerned about perforation; papillary
stenosis possible without pancreatic sphincterotomy; outcomes—with multiple sessions, ablation ≈90%, recurrence
≈10%, and morbidity acceptable; local surgical excision achieves similar results but higher recurrence likely
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| TOTAL MESORECTAL EXCISION: HOW I DO IT —David A. Rothenberger, MD, Professor and Interim Chair, Department
of Surgery, University of Minnesota Medical School, Minneapolis
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| Local recurrence of rectal cancer: rates vary widely from series to series; staging of tumors and surgeon expertise
likely reasons for variation; specialty training and high case volumes associated with good outcomes; concept of distal mesorectal
spread led to total mesorectal excision (TME) as curative technique
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| Preoperative measures: bowel preparation; deep venous thrombosis (DVT) prophylaxis; for distal tumor, consider bilateral
stoma marking because may have temporary ileostomy or permanent colostomy; consider ureteral stents for aggressive
large tumors in pelvis
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| Intraoperative measures: for positioning, speaker uses Yellowfin stirrups and keeps legs flat; place Foley catheter
and irrigate rectum; use illumination from sources other than just overhead light, eg, headlight; deep pelvic retractors essential;
important to have experienced team
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| Exploration: use midline incision; place self-retaining retractor; explore abdomen and confirm or revise operative plan
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| Colon mobilization: reflect rectosigmoid to right; incise peritoneum along left side of sigmoid; identify and preserve
gonadal vessels and ureter; incise peritoneum to splenic flexure; take down splenic flexure and divide splenic adhesions;
when mobilizing splenic flexure, lift colon up (do not pull down) and brush up back of descending colon with back of
hand to locate peritoneum tendon
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| Vascular pedicle ligation: reflect rectosigmoid anteriorly and to left; transilluminate mesentery; identify inferior mesenteric
artery (IMA) and superior rectal artery; incise peritoneum along right side of pelvis and locate free space next to
IMA (can follow IMA up to aorta); isolate and divide IMA; divide inferior mesenteric vein (IMV) proximally; divide colon
at sigmoid- descending junction (can use GI stapler)
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| Posterior pelvic dissection: retract rectosigmoid anteriorly and inferiorly (pull up toward pubis); often can follow air
dissection within areolar plane; go posterior to rectum but anterior to hypogastric nerve; use sharp dissection technique;
divide rectosacral fascia under direct view
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| Lateral pelvic dissection: follow posterior dissection and come out laterally on each side; maintain dissection in areolar/endopelvic
fascial plane; identify and preserve nervi erigentes; divide attachments anterolaterally; protect seminal
vesicles; nonoperative hand key to procedure by pulling hard to opposite side to give tension and show areolar plane
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| Anterior pelvic dissection: cul-de-sac opened; Denonvilliers fascia incised (fat looks different); protect prostate with
St. Mark’s and Wylie vein retractors; put patient in less Trendelenburg position
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| Bowel division: complete dissection of mesorectum or ≥5 cm; margin below tumor should be ≥2 cm; staple using triple staple
or contour staple technique; perform distal washout; divide rectum
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| ADJUVANT RADIATION FOR RECTAL CANCER: WHEN? HOW? HOW MUCH? —Robert Madoff, MD, Professor
of Surgery, Division of Colon and Rectal Surgery, University of Minnesota Medical School, Minneapolis
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| Disadvantages of radiation therapy (RT): cost; inconvenience for patients; complications; increases likelihood of
covering stoma after low anastomosis; impacts quality of life, particularly bowel function; bowel function—in Mayo
Clinic study, chemoradiation led to substantially worse bowel function, compared to surgery alone
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| Tumor staging: endorectal ultrasonography (ERUS) current technique of choice in United States; ERUS works well for
local excision, but cannot visualize outer margin of mesorectum; circumferential resection margin—positive margin
associated with significantly higher recurrence rates, compared to negative margin; high-resolution pelvic magnetic resonance
imaging (MRI) studies can preoperatively identify circumferential resection margin and can potentially guide therapy
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| Local recurrence: Swedish Rectal Cancer Trial—patients randomized to preoperative RT and surgery or surgery
alone; recurrence rate for surgery alone 27%, for RT plus surgery 11% (statistically significant); RT reduced local recurrence
in every stage, including early-stage tumors; Dutch TME trial—patients randomized to preoperative RT plus surgery
(TME) or surgery (TME) alone; local recurrence rate lower with RT plus surgery (2%), compared to surgery alone
(8%); RT reduced recurrence rate in all stages, except stage I; no difference in 2-yr survival
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| Preoperative RT: advantages—shrinks and downstages tumors; may improve resectability and sphincter sparing; decreased
risk to small bowel; biologically, RT more effective when tumor blood supply not disrupted; disadvantages—
not all patients staged accurately, so some patients receive RT unnecessarily; concern about healing anastomoses and
increasing operative difficulty
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| Postoperative RT: advantages—accurate staging; bowel healthy when anastomosis performed (no radiation to increase operative
difficulty); disadvantages—does not shrink tumors or maximize sphincter preservation; increased risk for small
bowel adhesion to old operative site; decreased function after RT
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| German Rectal Cancer Group study: patients with stage II to III rectal cancer randomized to preoperative or postoperative
chemoradiation; stricture rate and toxicity higher but completion rate lower for postoperative therapy; suggestion of improved
sphincter preservation and reduction of 50% in local recurrence with preoperative therapy; similar survival;
conclusions—preoperative chemoradiation therapy preferable
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| Administration of preoperative RT: long course—in United States, usual dose 45 Gy given over 6 wk preoperatively
(can be combined with chemotherapy); short course—in Europe, patients receive 25 Gy over 1 wk preoperatively (biologically
equivalent to US dose due to increased intensity); advantages include convenience, cost, and proven effectiveness; disadvantages
include requirement for skilled radiation therapist, concern over late toxic effects, and inability to combine with
chemotherapy
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| Treatment approach: stage patient optimally; conventional 5-wk RT with associated chemotherapy indicated for patients
with stage II (T3) or stage III (N1) tumors; postoperative chemoradiation indicated for patients with positive margins
(R1 resection)
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Educational Objectives
| The goal of this program is to educate the listener on issues in colon and rectal cancer. After hearing and assimilating this
program, the clinician will be better able to:
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| 1. Discuss the role of conventional colonoscopy in colorectal cancer screening.
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| 2. Manage upper gastrointestinal polyps in patients with familial adenomatous polyposis.
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| 3. Recognize when endoscopic papillectomy is indicated for resection of ampullary neoplasms.
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| 4. Perform a total mesorectal excision procedure.
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| 5. Review the data supporting use of adjuvant radiation therapy for rectal cancer.
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Suggested Reading
Birgisson H et al: Adverse effects of preoperative radiation therapy for rectal cancer: long-term follow-up of the Swedish
Rectal Cancer Trial. J Clin Oncol 23:8697, 2005; Bond JH: The case for direct colonoscopy screening for colorectal
cancer. Am J Gastroenterol 101:263, 2006; Dixon E et al: Transduodenal resection of peri-ampullary lesions. World J
Surg 29:649, 2005; Kapiteijn E et al; Dutch Colorectal Cancer Group: Preoperative radiotherapy combined
with total mesorectal excision for resectable rectal cancer. N Engl J Med 345:638, 2001; Martin JA, Haber GB: Ampullary
adenoma: clinical manifestations, diagnosis, and treatment. Gastrointest Endosc Clin N Am 13:649, 2003; Moore
E et al: Almost all five year disease free survivors are cured following rectal cancer surgery, but longer term follow-up detects
some late local and systemic recurrences. Colorectal Dis 7:403, 2005; Nelson DB: Appropriate use of surveillance
colonoscopy after polypectomy. Nat Clin Pract Oncol 2:22, 2005; Nelson DB et al: Procedural success and complications
of large-scale screening colonoscopy. Gastrointest Endosc 55:307, 2002; Pickhardt PJ: CT colonography (virtual
colonoscopy) for primary colorectal screening: challenges facing clinical implementation. Abdom Imaging 30:1, 2005;
Pickhardt PJ et al: Computed tomographic virtual colonoscopy to screen for colorectal neoplasia in asymptomatic
adults. N Engl J Med 349:2191, 2003; Read TE et al: Surgeon specialty is associated with outcome in rectal cancer
treatment. Dis Colon Rectum 45:904, 2002; Roggin KK et al: Limitations of ampullectomy in the treatment of nonfamilial
ampullary neoplasms. Ann Surg Oncol 12:971, 2005; Sauer R et al; German Rectal Cancer Study
Group: Preoperative versus postoperative chemoradiotherapy for rectal cancer. N Engl J Med 351:1731, 2004; Trimbath
JD et al: Attenuated familial adenomatous polyposis presenting as ampullary adenocarcinoma. Gut 52:903, 2003;
Wibe A et al; Norwegian Rectal Cancer Group: A national strategic change in treatment policy for rectal cancer-
-implementation of total mesorectal excision as routine treatment in Norway. A national audit. Dis Colon Rectum 45:857,
2002; Winawer S et al: Colorectal cancer screening and surveillance: clinical guidelines and rationale-Update based on
new evidence. Gastroenterology 124:544, 2003; Wong RF, DiSario JA: Approaches to endoscopic ampullectomy.
Curr Opin Gastroenterol 20:460, 2004.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial relationship
with the manufacturer or provider of any commercial product or service discussed. For this issue, the speakers reported
nothing to disclose.
Drs. Bond, Freeman, Rothenberger, and Madoff were recorded September 9, 2005, in Minneapolis at the 68th Annual
Colon and Rectal Surgery: Conundrums and Controversies, presented by the University of Minnesota Medical
School. The Audio-Digest Foundation thanks the speakers and the University of Minnesota Medical School for their
cooperation in the production of this program.
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