CRC Screening

Colorectal Cancer Screening

“Colorectal cancer commands the attention of [us all] because it is one of the most lethal diseases that we deal with, it occurs frequently (and silently), and it is a disease for which we have the greatest ability to intervene and alter the natural history in a dramatic way.”

C. Richard Boland, MD

How lethal is CRC?

• CRC is the third most common internal cancers in men & women

• CRC is the second leading cause of cancer death

• CRC is the leading cancer death in men and women who do not smoke

• We each have a 1 in 18 chance of developing the disease

Deaths in USA• 150,000 new cases of CRC each year• 57,000 people died from CRC yearly

– ½ are women– Typically affects people 50 yrs and older– Men have > risk of CRC but more women die of

CRC because they live longer– Relative risk highest amongst African-American– CRC can be heredity

• Familial Adenomatous Polyposis [FAP], 1%• Hereditary nonpolyposis CRC, [HNPCC] 5%• Family Hx of CRC or adenomas, 18-23%• Personal Hx of prior colon cancer, long standing IBS,

Crohn’s, ovarian, endometrial and probably breast cancer

• Most cases are sporadic in average risk patients, 65-85%

Deaths World Wide

• CRC is the 4th most common cancer world wide

• New cases yearly– 400,000 in men– 380,000 in women

• Almost 400,000 deaths yearly– CRC is the 1st most common cause

of cancer in the European Union (1)

What else do we know about CRC?

•Through screening, CRC is the most preventable visceral

cancer.

Currently there is a low level of CRC screening.

This is due to:

Physician, then patient attitudes about current screening methods.

• In order to “beat” a problem, it is wise to learn everything about it you possibly can.

SO…..

What are the contributors to CRC?

• Older Age• Ethnicity• Personal/Family history of CRC• Polyps

– Present in 10-30% of population by age 50 yo– Present in 30-60% of population by age 70-75 yo– Reduced incidence of CRC when polyps are

removed

• Diet high in meat, fat, protein, or alcohol & low in fiber, calcium, selenium, or folate are associated with increase in CRC

What are the distracters to CRC?

• Young Age/However occurs 7% in people <50

• Ethnicity• No Personal/Family history of CRC/However

80% occurs in people without history• Diet low in meat, fat, protein, or alcohol &

high in fiber, calcium, selenium, or folate are associated with decrease in CRC

• HRT decreases CRC• ASA & NSAIDS may reduce CRC• Lifestyle can affect risk, decreasing CRC

with exercise & healthy eating.• BUT in particular…screening for CRC, BUT in particular…screening for CRC,

decreases CRC.decreases CRC.

Screening Facts

• 60% of Americans over 50 have NEVER been screened for CRC

• ALL FORMS OF SCREENING REDUCES MORTALITY

• Screening detects and removes pre-cancerous polyps

• Screening is cost-effective

According to Vogelstein @ John Hopkins..

NormalAdenoma Advanced

Adenoma

Early Carcinoma

Colonic epithelium

Benign neoplasia Lasting many

decades

Benign, 2 -5 years

Malignant neoplasm

Late Carcinoma

2 -5 years

Benign neoplasia

…we may have decades plus/minus 10 years to find CRC!

EARLY DETECTION IS THE KEY!

Even if we don’t get CRC in the adenoma stage, localized CRC 5-yr survival rate is 90% compared to 5% with metastasizes.

Who do you screen?• The Average Risk Person [ARP] = is 50 yo or older

without other risk factors for CRC = 75-80% of the at risk population

• Other high risk patients should be screened earlier = 25-20% of the at risk population

• Lowest screened:– People aged 50-54 (31%)– Hispanics (31%)– Asian/Pacific Islanders (35%)– People < 9th grade education (34%)– No Health Care (20%)– Medicaid Coverage (29%)– No medical care during last year (20%)– Daily smokers (32%)– More screening in New England / Mid-Atlantic– Less screening in Gulf/South

High Risk People = 20-25% of population

• People with HNPCC diagnosis – These people get CRC at 45 yo instead of the common

age of 63 yo– Also increased in people with endometrial, ovarian,

breast cancer– Begin screening at 20 -30 yo– High suspicion when they follow the “Rule of 3-2-1”

[Amsterdam II criteria]• 3 relatives with CRC/at least one is first degree relative of

the other two• 2 successive generations• 1 diagnosis before the age of 50

– Mutation in the hMSH2 & hMLH1 genes [signaling proteins responsible for gene repair] that increases microsatelitte instability [MSI] = Hallmark of HNPCC

More High Risk• People with Familial Adenomatous Polyposis,

FAP– 50% have polyps in teens– 95% have polyps by 35 yo– 100% have CRC by 40 yo unless their colon is

removed – Mutation in the APC [adenomatous polyposis coli]

gene responsible for tumor suppression• Ashkenazi Jews

– 6% population has double the risk of CRC – Mutation in APC tumor suppressor gene

• African American men & women– Develop CRC more commonly on the right side of

the colon. May be missed depending on screening modality.

Fact!

Every man and woman 50 years or older is at risk for the development of CRC.

CRC Screening Options for PatientsPresented in 1997 by AGA*

• Annual Fecal Occult Blood Testing [FOBT]

• Flexible sigmoidoscopy every 5 yrs• Annual FOBT plus flexible sigmoidoscopy

every 5 yrs• Double-contrast barium enema every 5

yrs• Colonoscopy every 10 yrs

*American Gastroenterological Association

Patient Selection of Options• Almost noninvasive

– 31% chose FOBT only

• Invasive procedures:– 38% chose colonoscopy, most preferred

invasive option– 14% preferred barium enema– 13% preferred flexible sigmoidoscopy

• 71% chose to repeat colonoscopy – 36% chose to repeat FOBT

Why patients don’t participate…..

• Fear of pain, embarrassment, distaste• Lack of perceived need• Fear of the results• Fatalism [belief nothing can be done]• Too busy, not willing to take time off for

screening• Inadequate transportation and telephone

service• Deference to authority• Lack of screening coverage by health plan

or no insurance

Why patients do participate…..• Clinician advise• Perceived benefit [test as effective]• Family member who has had the test• Continuing relationship with the practitioner• Higher socioeconomic status• More personal experience of illness• Regular preventive health behavior [dentist, use of

seatbelts]• Family history of CRC• Age under 75 yrs• Being married• Belief that CRC is curable• Other GI symptoms [stomach symptoms,

haemorrhoids]

How to get patient cooperation…

… physicians must first OFFER patients a controlled screening choice.

To date, all choices of CRC screening have been based on an understanding of disease that originated 30 years ago. A time when many of our current medical physicians were beginning their careers. These classifications were based on morphological differences; tumors were grouped according to levels of differentiation, gland formation, etc, but gave little insight into clinical management according to biological type.

Today…..

• ….we are beginning to understand the biological concepts of CRC

To access additional information on the biological types of CRC, click on the

below link.

Biological concepts of Colorectal cancer

Thus in 2003 two more modalities were added to our current

screening procedures. – One, a marketing venture called “Virtual

Colonoscopy” Known as CT Colonography in the medical world.

– Two, a biological “hands-off” testing that relies on the current understanding that CRC is the end result of a heterogeneous group of processes that alter the biological characteristics of colorectal epithelium

2004’s Available Screening Modalities

• FOBT-Fecal Occult Blood Testing– Digital Rectal Exam [DRE] - is NOT a

screening Test for CRC

• Flexible Sigmoidoscopy• Double Contrast Barium Enema• Colonoscopy [Screening &

Diagnostic]• Stool-based DNA Testing• Virtual Colonoscopy

Testing OptionsTest Performed

byInvasiveness Test

SensitivityCompliance

[Risks]Timed

IntervalsEffective Cost

FOBT3 samples

Patient, Must handle

stool

Noninvasive Not diagnosticLow

30-50%

Variable50%

^Annually,rehydration

^^Biennial

^40% reduction CRC

^^30% reduction

$5 - $7

Sigmoidoscopy

Physician, PA, N P

Invasive 50-70% but misses lesions

proximal to the scope.

[With FOBT inc to 76%]

Bowel prep /No anesthesia,

may be uncomfortable/ Perforation [1:10,000]

Every 5 yrs. Less likely to repeat due to discomfort.

Not firmly effective, must be used with

FOBT.

$180 - $350

Double Contrast Barium Enema

Qualified Physicians

Invasive Low sensitivity Bowel Prep/Uncomfortable

/Perforation 1/25,000.

No studies show

effectiveness

Not preferred if other screens are available

$200

Colonoscopy“Gold

Standard”

Qualified Physicians

Invasive Highest sensitivity may prevent 76 to 90% cancers

Bowel Prep/ Anesthesia,

thus variable /Perforation

risk 1:500 to 1:4000

Longest interval

protection/every 10 yrs as screening

tool

Only test that is screening,

diagnostic and therapeutic

during a single procedure

$2000-$3000

Stool-based DNA Testing

Patient, No direct

stool handling

Noninvasive/ Testing is

representative of entire

colon

65-70% decrease in

CRC mortality

High compliance expected.

Expected to be high

Every 3 to 5 yrs. Interval not clearly

determined.

Projected sensitivity less

than colonoscopy

$800

Virtual Colonoscopy

[CT Colonography

]

Qualified Physicians

Minimally Invasive

>10mm lesions same

as Colonoscopy<5mm&flat

lesions mixed to poor

Bowel Prep is uncomfortable, procedure is

not.Variable

Every 5 to 10 years

Most expensive diagnostic test /

No direct evidence of

effectiveness

$500-$1000

Clinical Decisions in CRC Screening

• Patient considerations:•Patient finances•Patient risk•Patient compliance

– Initial–Repeat

• Screening considerations•Testing effectiveness

Knowing that “all asymptomatic people 50 yr old and older should be screened

for CRC,” what is your choice?

• FOBT, annually with colonoscopy if positive• FOBT, annually with sigmoidoscopy every 5 yrs

starting at 50• Double Contrast Barium Enema

– [Not preferred if other screens are available]

• Virtual Colonoscopy every 5 to 10 yrs • Colonoscopy every 10 yrs• DNA Testing every 3 to 5 years• DNA Testing every 10 yrs with Colonoscopy

every 5 yrs spaced between the colonoscopies

What is the BEST Screening Plan for the Average Risk Patient?

The plan that is followed through on!!!The plan that is followed through on!!!

Otherwise….

Colonoscopy every 10 yrs with DNA testing every 5 yrs spaced between the Colonoscopy beginning at an earlier age than 50 yo for the high risk patients

Recently due to scientific studies……

…doctors are realizing colon cancer is an ubiquitous disease with many paths and many “reactive treatments” when the disease is diagnosed. [ie,surgery, chemotherapy, radiation]

• Because of this, and the desire to find more cost-effective therapies, the concept of chemopreventionchemoprevention has evolved….high risk patients take some drug or nutritional substance long term to help lower their risk of CRC.

Sound like Functional Medicine?Sound like Functional Medicine?

Colon Chemoprevention

• The substances being investigated are:– A FDA approved statin– A novel nutritional agent that contains inulin– NSAIDS

• To learn more about Mayo’s Chemoprevention Clinical Trials, contact Paul Limburg, MD, MPH, at 507-266-4338

SO……….

• Click on this link and fill out the consent form.

• Make a choice to NOT become a Colorectal Cancer statistic!

• THANK-YOU and your loved ones thank-you too!

ResourcesAmerican Cancer Society http://www.cancer.org

American College of Gastroenterology http://www.acg.gi.org

American Academy of Family Physicians http://www.aafp.org

American Gastroenterology Association http://www.gastro.org

American Society of Colon and Rectal Surgeons http://www.fascrs.org

American Society of Gastrointestinal Endoscopy http://www.asge.org

Cancer Care http://www.cancercare.org

Cancer Facts http://www.cancerfacts.org

Cancer Research Foundation of America http://www.preventcancer.org

National http://www.nccra.org

Colon Cancer Alliance http://www.ccalliance.org

Colorectal Cancer Network http://www.colorectal-cancer.net

Harvard Center for Cancer Prevention http://www.hsph.harvard.edu/cancer

Centers for Disease Control and Prevention http://www.cdc.org

National Cancer Institute http://cancernet.nci.nih.govhttp://rex.nci.nih.gov

Oncolink http://www.oncolink.upenn.edu

References

• 1.http://www.foodingredientsfirst.com/newsmaker_article.asp?idNewsMaker=83&fSite=E0D45&nw=hd