1. Colorectal Cancer Screening and Postoperative Follow-Up

2. Colorectal Cancer (CRC)
Incidence
2nd commonest cause of cancer deaths in males
3rd commonest cause of cancer deaths in females
Lifetime risk
2015 (Canada)
25,000 People diagnosed with CRC (45/100,000)
9,300 Canadians died from CRC (17/100,000)
Lifetime Risk M F
Developing CRC (Canada) 6% 7%
Dying from CRC (Canada)
3.5%
3.1%

3. Types of Malignant Colorectal Cancer
Adenocarcinoma
Carcinoid
Lymphoma
Sarcoma
Squamous Cell Carcinoma
Plasmacytoma
Leukemic Infiltrate
Melanoma – more common anus vs rectum
Metastatic Carcinomas

4. Risk Factors for CRC Age Race Sex (M>F) Diet/Social Habits
Lower risk for Hispanic and Native Indians
Diet/Social Habits
Family History
Increased risk with alcohol consumption
Associated Illnesses
No link with smoking
Obesity
IBD
Diet – increased with diet high in saturated fats and proteins
Polyposis Syndromes
Decreased risk with high fiber diet
Geography
Occupations Associated with Higher Risk
Firemen
Factor Workers (Synthetic Fibers)
Metallic Workers
Asbestos Exposure

5. “Recommendations on Screening for colorectal cancer in primary care
“Recommendations on Screening for colorectal cancer in primary care.” Canadian Task Force on Preventative Health Care.
CMAJ Mar 2016, 188(5)

6. Screening For Colorectal Cancer
Rational – Lower deaths and incidence of CRC by
Earlier detection
Removing polyps that may transform
Identifying higher risk patients that require increased surveillance

7. Symptoms ≠ Screening

8. Symptoms Rectal Bleeding Change in Bowel Habits Abdominal/Pelvic Pain
Bloating
Weight Loss
Nausea/Vomiting
Anemia/Fatigue
Fistula Symptoms

9. Most (“All”) CRCs arise from colon polyps
Polyp to cancer sequence
Slow transformation to invasive carcinoma
Only a limited proportion of polyps develop into CRC

10. Polyps – Histologic Types
Neoplastic
Tubular Adenoma (75%)
Tubulovillous Adenoma (15%)
Villous Adenoma (10%)
Sessile Serrated Adenomas
Hamartomatous
Juvenille Polyps
Peutz-Jeghers Syndrome
Cronkhite-Canada Syndrome
Inflammatory Polyps
Inflammatory
Pseudopolyps
Lymphoid Polyps
Hyperplastic

11. Neoplastic Polyps Risk for malignant transformation Size
Villous>Tubulovillous>Tubular
Size
Increased risk with larger size of polyp
Rare < 1cm
Polyp Morphology

12. Summers, Ronald M. “Polyp Size Measurement at CT Colonography: What Do We Know and What Do We  Need to Know?” Radiology (2010): 707–720. PMC. Web.

13. Concerns About Screening for CRC
Detection Rates
Cost Effective
Adverse Effects of Test
Complications of procedure
Perception/Task to complete procedure
Frequency of Screening Test
Minimizing False Positive Rate

14. Screening Tests Guaiac Fecal Occult Blood Test (FOBT)
Fecal Immunochemical Test (FIT)
Flexible Sigmoidoscopy
Colonoscopy
Radiological Studies
CT Colonography
Ba Enema
Other
Fecal DNA Testing
KRAS mutations
Abberant NDRG4
BMP3 Methylation
Hemoglobin Immunoassays

15. Not Approved Screening Tests
CEA
Colonoscopy ?

16. CRC Screening 2001 Canadian Task Force on Preventative Health Care
Annual or Biennial FOBT and Flexible Sigmoidoscopy every 5 years
(In asymptomatic individual > 50 years old and who are not at high risk)

17. CRC Screening Current Guideline (Provincial Variation)
Age (Weak Recommendations)
FIT or FOBT every 2 years OR
Flexible Sigmoidoscopy every 10 years
Age (Strong Recommendations)

18. CRC Screening Cont. * Age 75+ (Weak Recommendation)
Screening generally not recommended
Decision based on reduced life expectancy in older age group
No high powered RCTs to show benefit for elderly in lowering mortality/morbidity
Higher incidence  ? screening more frequently
Patient dependant decision *

19. “Recommendations on Screening for colorectal cancer in primary care
“Recommendations on Screening for colorectal cancer in primary care.” Canadian Task Force on Preventative Health Care.
CMAJ Mar 2016, 188(5)

20. High Risk Patients History of previous adenomatous polyps
Family history of CRC/(Polyps?)
Associated Illness
Inflammatory Bowel Disease
Ulcerative Colitis
Crohn’s Colitis
Polyp Syndromes
Familial Adenomatous Polyps (FAP)
Lynch Syndrome
Others
Associated Malignancies

21. Inflammatory Bowel Disease (IBD)
Ulcerative Colitis and Crohn’s Colitis: both associated with increased CRC risk
CRC risks - colitis proximal to splenic flexure
Risks CRC
5% after 10 years
20% after 20 years
40% after 25 years
Decreased risk with left sided disease only
Minimal risk with ulcerative proctitis
Increased risk in IBD patients with:
“severe” inflammation
Prolonged active disease
More extensive disease (proximal to splenic flexure)
Sclerosing cholangitis as part of IBD secondary symptoms
Family history CRC

22. Recommendations of Screening IBD
Colonoscopy
Every 1-3 years after 8-10 years active disease (Mine every 2 years)
Left sided only - after 15 years?
At start of diagnosis of sclerosing cholangitis
Random biopsies 4 quadrants every 5 to 10 cms
Attention to – strictures and mass lesions
Difficulties - pseudopolyps
High risk factors on colonoscopy for IBD
High grade dysplasia (HGD)
Multifocal low grade dysplasia (LGD)
Dysplasia associated with mass lesion (DALM)

23. Familial Adenomatous Polyposis (FAP)
<1% of CRC cases
Autosomal dominant syndrome
100’s-1000’s of colorectal polyps
50% of patients have polyps by age 15
95% by age 35
Lifetime risk CRC ≈ 100%
Average age of diagnosis of CRC years

24. Familial Adenomatous Polyposis (FAP) Cont.
Screening
Genetic Testing of affected individual
If positive for gene
Screening with colonoscopy start as teenager
Prophylactic total proctocolectomy
Anything less
Screen remaining colon/ rectum q yearly
UGI Screening with < EGD
Increased risk duodenal/periampullary cancers
If negative
Higher surveillance until age 40
If normal until then assume normal risk screening protocol

25. Lynch Syndrome (Hereditary Nonpolyposis CRC)
Associated with 2-3% of all CRC cases
Autosomal dominant syndrome
Mutation of DNA mismatch repairing
Lifetime risk of CRC is approximately 70%
Presents at earlier age
More right sided CRC
Characteristic histologic changes
Increased incident synchronous/metachronous
High risk of other cancers
Ovary and uterus
Stomach
Pancreas
Ureter/Renal Pelvis
Small Bowel
Biliary Tract
Brain

26. Screening Recommendations
Colonoscopy starting at 25 (10 years before youngest affected individual)
Repeat every 1-3 years
Screen for other cancers
Especially GU
Stomach

27. Peutz-Jeghers Syndrome
Autosomal dominant syndrome
Polyps anywhere in GI tract
Predominantly small bowel
Lifetime risk of CRC ≈ 10%
Associated with other cancers
Stomach
Pancreas
Small Bowel
Ovary
Uterus
Cervix
Testicle
Pituitary
Screening
Colonoscopy every 3 years
EGD every 2 years
Small bowel investigation every 2 years
GU?

28. Screening in Patients with History of Adenomatous CR Polyps
Purposes of surveillance
Detect/Remove new polyps
Detect and remove polyps missed during previous scopes
High risk factors with adenomatous polyps
Adenomas > 10mm
Multiple adenomas (>3 per colonoscopy)
Advanced Histology
Villous adenoma
High grade dysplasia
Proximally located polyps?
Older age
Family history of CRC in 1st degree relative
Large polyps
Increased risk of local recurrence

29. Follow Up Recommendations in Patients With Known CR Polyps
2 or less polyps <10mm adenoma
Colonoscopy 5 years (GI)
Colonoscopy 3 years (ACS)
1 Polyp > 10mm
Colonoscopy every 3 years
3 or more adenomatous polyps
Advanced histology
Colonoscopy every 3 years or less

30. Colorectal Cancer History Follow-Up (My Guidelines)
History and exam every 3 months for 5 years
CBC, LFTs*, CEA*, every 3 months for 5 years
PSA yearly with APR patients
CT scan yearly for 5 years *
CT Chest, abdomen and pelvis
Colon cancer – colonoscopy 1 year after resection and if normal every 3 years*
Rectal cancer*
Flexible sigmoidoscopy 6 months after
Colonoscopy at 1 year
Then repeat flex sigmoidoscopy at 18 months/colonoscopy at 2 years
Colonoscopy every 3 years after if normal *
= only do test if prepared to deal with findings. Ie metastatic disease