COLONIC POLYPSMay occur in any part of the colonMajority of them arise in the rectum and

sigmoid colonThey tend to cause rectal bleeding (visible

or occult) and may undergo malignant change

If rectal polyps are found, the entire colon must be investigated- total colonoscopy

The larger the lesion the more likely it is to be malignant

COLORECTAL POLYPSHistopathologically- three patterns of growth:

tubular adenomas

villous adenomas

tubulo-villous adenomas

PHYSICAL EXAMINATIONGeneral examination- features suggesting

malignant disease:Obvious weight lossPalor of the skinAbdominal distentionHepatomegalyAbdominal mass

PHYSICAL EXAMINATIONRectal examination:

Finger can reach lesions as far as the its length 7-9 cm

Palpable fixed mass in Douglas pouch-sigmoid tumor dropped retrorectally

The glove inspected for blood and mucus

Types of Colon Cancer Types of Colon Cancer

Familial15%

Hereditary4%

Sporadic80%

IBD1%

Risk Factors

Nearly 90% of colon cancer patientsare over the age of 50.

Other risk factors include:

family or personal history of colon cancer or polyps

chronic inflammatory bowel disease hereditary colorectal syndromes use of cigarettes and other tobacco products high-fat/low fiber diet physical inactivity

Nearly 90% of colon cancer patientsare over the age of 50.

Other risk factors include:

family or personal history of colon cancer or polyps

chronic inflammatory bowel disease hereditary colorectal syndromes use of cigarettes and other tobacco products high-fat/low fiber diet physical inactivity

Risk increases with age

Symptoms

Signs and symptoms typically occur only in advanced colon cancer. Symptoms may include:

Change in bowel habits lasting more than a few days

Bleeding from the rectum

Blood in the stool

Cramping or gnawing stomach pains

Weakness and fatigue

Jaundice (yellow-green color of the skin & white part of the eye)

Signs and symptoms typically occur only in advanced colon cancer. Symptoms may include:

Change in bowel habits lasting more than a few days

Bleeding from the rectum

Blood in the stool

Cramping or gnawing stomach pains

Weakness and fatigue

Jaundice (yellow-green color of the skin & white part of the eye)

Early colon cancer usually has no symptoms

Colon Cancer TestsColon Cancer TestsFecal occult blood testing (FOBT)Barium enemaFlexible sigmoidoscopyColonoscopyVirtual Colonoscopy

Get the test. Get the polyp. Get the cure.

                                                                                    

                              

ColonoscopyColonoscopy

ColonoscopyColonoscopy

AdvantagesDetects >90%

polyps and cancerProvides diagnosis

and therapyMedicare covers

average-risk

LimitationsRisksAvailabilityCostCompliance

Get the polyp. Get the cure.

Testing rates remain far too lowTesting rates remain far too low

Are people getting tested?Are people getting tested?

Fewer than half of Americans over age 50 report having had a recent colorectal cancer screening test

Because of low testing rates, only 39% of colorectal cancers are detected at the earliest, most treatable stage

Ethnic/Racial differencesEthnic/Racial differencesPercentage who have never had

screening colonoscopyHispanics - 67%Black - 55.8%White, non-Hispanic – 47%Never married 60%Education less than high school diploma

58% vs 52% completed high school vs 46% with some college education

2005 data, AHRQ2005 data, AHRQ

                                                                                      

              

Virtual ColonoscopyVirtual Colonoscopy

Virtual ColonoscopyVirtual Colonoscopy

Spiral CT to generate 3D imagesCleaning of bowel, distension with airNon invasive, no complicationsNot endorsed for CRC screening

                                                                                                  

Virtual ColonoscopyVirtual Colonoscopy

Limitations Virtual Colonoscopy Limitations Virtual Colonoscopy

Variable resultsNo screening studiesNo longitudinal studiesCostDoes not allow for therapy

Stool DNAStool DNANow recommended by ACS and USMSTF for

average risk individualsMulti-target DNA stool assay required to

achieve adequate sensitivity and detect the various gene mutations

K-rasK-ras

APCAPC

P53P53

BAT-26BAT-26

21 separate point mutations21 separate point mutations

DIADIA

Video Capsule ColonoscopyVideo Capsule ColonoscopyIn the process of development

Battery lifeNo clinical data availableAnticipate to see clinical trials

Colon Cancer TestsColon Cancer TestsAverage RiskAverage Risk

                                      

Average Risk IndividualsAverage Risk Individuals

No SymptomsAge 50No risk factors

Current RecommendationsCurrent RecommendationsAverage RiskAverage Risk

*Preferred strategy by ACG*Preferred strategy by ACG

Test Interval (years)

FOBT Yearly

Sigmoidoscopy Every 5

FOBT + Sigmoidoscopy Yearly, every 5

Colonoscopy Every 10*

Barium enema Every 5

Approach to Colon Cancer TestingApproach to Colon Cancer Testing

AsymptomaticMen and Women

Age < 50 yr

No family Hx

No Screening

HNPCC or FAP

Genetic Counseling

1 first-degree 60 yrs

Average-riskscreening,

starting age 40

YES family Hx

2 or more first-degree or 1 first-degree < 60 yrs

Colonoscopy every5 yrs, starting age 40

Age 50 yr

NO family Hx

Average Screening

The flat polypThe flat polyp

Techniques to improve detectionNarrow-band imagingChromoendoscopyEndocytoscopy

Soitenko et al. JAMA Soitenko et al. JAMA March 2008March 2008

Narrow Band ImagingNarrow Band Imaging

Left sided ulcerative colitis Left sided ulcerative colitis

Ulcerative colitis with extensive Ulcerative colitis with extensive pseudopolypspseudopolyps

FAMILIAL POLIPOSIS COLIIt is a rare autosomal dominant disorderMultiple colorectal polypsRectal bleeding/ change in bowel habitThe treatment- colorectal removal with

ileoanal anastomosis, or panproctocolectomy with definitive ileostomy

Peutz-Jeghers syndromeIt is an autosomal dominant inherited disorder

characterized by intestinal hamartomatous polyps in association with mucocutaneous melanocytic macules.

Patients with Peutz-Jeghers syndrome (PJS) have a 15-fold increased risk of developing intestinal cancer compared with that of the general population.

Such cancer locations includes gastrointestinal and extraintestinal sites.