1. Screening and Early Diagnosis of Colorectal Cancer
Shaimaa M.Nagy
Faculty of Medicine, Benha University

2. Incidence of CRC
CRC is the 3rd most common form of cancer diagnosed in men and women in the US
CRC is the 2nd leading cause of cancer deaths in the US
The number of people dying from CRC has declined over the past 20 years with better screening, diagnosis and treatments

3. ch.ch. of CRC in Egypt:
• Relative frequency 10-12% • High male predominance 3:1 • More than 1/3 under age 45 (early onset) • Large tumor size 4.5 cm • rectal 51%, poor histology 58% • Associated bilharzial colitis 12% • Associated polyps 5% • Sporadic , HNPCC

4. Symptoms and signs
A change in bowel habits: diarrhea, constipation, or a feeling that the bowel does not empty completely
Bright red or dark blood in the stool
Stools that appear narrower or thinner than usual
Discomfort in the abdomen, including frequent gas pains, bloating, fullness, and cramps
Unexplained weight loss, constant tiredness, or unexplained anemia (iron deficiency)

5. Colorectal Cancer 80% present with early disease
RCF-10 CRC Slides Section A
4/19/2017 3:42 AM
Colorectal Cancer
80% present with early disease
20% present with metastatic disease.
Among patients diagnosed with early-stage disease, 40% will suffer recurrence.
Stage at Diagnosis
Distant
(Stage IV)
20%
Localized
(Stage I/II)
50%
Numbers for stage at diagnosis may not add up to 100% due to the presence of unknown stage or unstaged disease in patients at diagnosis.1
Only 39% of CRC cases are diagnosed early in stage I and II.
This reflects the often asymptomatic nature of early disease.
The majority of CRC cases (57%) are diagnosed in later disease stages.
Nineteen percent are diagnosed with distant metastases (stage IV).
Among patients with metastatic disease, the median 5-year survival is only ~10%.
1. Jemal A, et al. CA Cancer J Clin. 2007;57;43-66.
Regional
(Stage III)
30% 5

6. Risk Factors for CRC Age >50 (average risk) Racial, ethnic factors
RCF-10 CRC Slides Section A
Risk Factors for CRC
4/19/2017 3:42 AM
Age >50 (average risk)
Racial, ethnic factors
– African-Americans have increased risk
Dietary factors
– high animal fat, low fiber diet
Lifestyle
– Sedentary
– Obesity
– Smoking
– Alcohol
-genetic factors
-sporadic 6

7. Lifestyle Risk Factors for Colorectal Cancer
RCF-10 CRC Slides Section A
4/19/2017 3:42 AM
Lifestyle Risk Factors for Colorectal Cancer
Decrease Risk
Exercise
Folic acid
Aspirin
Calcium, vitamin D
Screening
Increase Risk
Obesity
Red meat
Alcohol
Smoking 7

8. Colorectal Cancer (CRC)
RCF-10 CRC Slides Section A
4/19/2017 3:42 AM
Sporadic
(average risk)
(75-80%)
Family
history (10-15%)
Rare syndromes (<0.1%)
Hereditary non-polyposis colorectal cancer (HNPCC) (3-5%)
Familial adenomatous polyposis (FAP) (1-2%) 8

9. Precancerous lesions:
Polyps
IBD

10. Histological classification of polyps
type
single
multiple
neoplastic
Adnoma ( T,V,TV)
adenocarcinoma
adenomatosis
hyperplastic
Hyperplastic polyposis
hamartomatous
Juvenile polyp
Peutz-jegher syndrom
Peutz jegher
cowden
inflammatory
Parasitic
psuedolymphoid
Parastic, inflammatory

11. Natural History Advanced cancer Polyp
RCF-10 CRC Slides Section A
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Advanced cancer
Polyp
• Age 50, 25% risk of developing polyps
• Age 75, 50-75% risk of developing polyps 11

12. RCF-10 CRC Slides Section A
4/19/2017 3:42 AM 12

13. IBD: Classification of Dysplasia
• Negative for dysplasia
Normal
Inactive colitis
Active colitis
• Indefinite for dysplasia
• Positive for dysplasia
Low-grade dysplasia
High-grade dysplasia

14. Carcinoma in Inflammatory Bowel Disease
• Extensive colitis 13% • < 10 years < 1% • 15 years 4.5% • 20 years 13% • 30 years 34% • Crohn’s disease 3%

15. Colorectal Cancer and Early Detection
Colorectal cancer can be prevented through regular screening and the removal of polyps
Early diagnosis means a better chance of successful treatment
Screening should begin at age 50 for all “average risk” individuals or sooner if you have a family history of colorectal cancer, symptoms, or a personal history of inflammatory bowel disease

16. Screening Methods for Colorectal Cancer
History and general examination
• Rectal examination
Colonoscopy (currently the best way to prevent and detect colorectal cancer)
Virtual colonography
Sigmoidoscopy
Fecal occult blood test
Double contrast barium enema
Digital rectal examination
• Serum CEA, CA 19-9, CA 72.4
CBC, ESR, Ca and folic acid detection

17. Fecal Occult Blood Test (FOBT)
Recommended to be done yearly
Checks for hidden blood in the stool
Your doctor gives you a test kit
At home, you place a small amount of your stool from 3 bowel movements on test cards.
You then return the cards to your doctor’s office or a lab where the stool samples are tested for hidden blood.
If blood is found, a colonoscopy will be needed.
A disadvantage of this test
The test is often negative in people who have adenomatous polyps and colorectal cancer

18. Flexible Sigmoidoscopy (Flex Sig)
Recommended every 5 years
Examines the lining of rectum and lower part of colon
Uses a thin, flexible, lighted tube called a sigmoidoscope
It is inserted into your rectum and lower part of your colon.
If polyps or lesions are found, a follow-up test is needed.
Disadvantages:
Patient discomfort – but not painful
Only looks at lower part of colon, therefore polyps in the upper colon can go undetected.
If a polyp is found, it needs to be followed by a colonoscopy to remove the polyp

19. Combination FOBT and Flex Sig
Some experts recommend using both of these tests to increase the chance of finding polyps and cancers.
It is recommended every 5 years

20. Colonoscopy Similar to the Flexible Sigmoidoscopy except:
It allows the doctor to look at the lining of your rectum and entire colon.
Done as an outpatient procedure
Done with “conscious sedation”
An IV line is inserted to help you remain calm and comfortable. Some patients sleep though the procedure.
Not everyone needs sedation.
Uses a thin, flexible, lighted tube called a colonoscope
It is inserted into your rectum and colon.
The doctor can also find and remove polyps and some cancers using the colonoscope.
It is recommended every 10 years for:
Individuals with no family or personal history of colon cancer and no symptoms.

21. Colonoscopy (continued) …
Procedure takes 15–30 minutes.
May take longer if polyps are removed.
Called a polypectomy
A wire loop is passed through the scope to cut the polyp from the lining of the colon using an electrical current.
Polyps are collected and sent to the lab for evaluation.

22. Double Contrast Barium Enema (DCBE)
This test allows the doctor to see an x-ray image of the rectum and entire colon.
First you are given an enema with a liquid called barium that flows from a tube into your colon, followed by an air enema.
The barium and air create an outline around your colon, allowing the doctor to see if anything is wrong.
Recommended every 10 years.
Many disadvantages:
Detects only 50 percent of adenomatous polyps greater than 1 cm in size and only 33 percent of polyps .5 cm in size
May miss up to 15 percent of colorectal cancers
Does not allow removal of polyps

25. Take Home Message

26. Screening = Prevention & Early Detection
Prevention = polyp removal
Decreased Incidence
Early Detection Decreased Mortality

27. THANK YOU