Colon Cancer Sreening
Recommendations
Jose M Nieto DO FACP FACG AGAF FASGE
Borland Groover Clinic
DISCLOSURE
No financial disclosures
Outline
1. Review SCREENING recommendations
2. Colon Polyps
A. Non-neoplastic polyps
B. Neoplastic polyps
i. Serrated polyps
ii. Adenomatous polyps
3. SURVEILLANCE recommendations
A. Low-risk adenomas
B. High-risk adenomas
C. Serrated polyps
4. Quality indicators for Colonoscopy
5. Emerging technologies
A. Stool DNA testing
B. CT Colonography
6. Summary
Colorectal Cancer
COMMON PROBLEM:
3rd incident cancer (150,000/yr)
2nd cancer mortality (50,000/yr)
Lifetime incidence 5%
GOOD NEWS:
Incidence & Mortality is declining
53% reduction due to screening (Edwards BK, Cancer 2010)
1987-2010: ¼ - ½ million cases prevented (Yang DX, Cancer 2014)
Other reasons:
decreased exposure to risk factors
improved therapy
CRC Screening
GOAL:
Decrease mortality by decreasingn incidence of
advanced disease
EARLY DETECTION:
5-yr survival (%)
LOCALIZED (bowel wall)
90
REGIONAL (LNs)
68
DISTANT (metastases)
10
PREVENTION:
Detection / removal adenomas
CRC Screening Guidelines
1. American Cancer Society (1st in 1980)
2. USPSTF
3. ACR
4. USMSTF (2012 SURVEILLANCE)
5. ACS-USMSTF-ACR (2008 SCREENING)
6. ACG
7. NCCN
8. ACP stetements
9. Council of European Union
CRC Screening Guidelines
2008 ACS-MSTF-ACR
Primary goal: PREVENTION
Sensitive test @single point in time preferred over repeated testing
Start age 50
Stop when life expectancy <10 yrs
STOOL BASED TESTING:
gFOBT, iFOBT, sDNA
STRUCTURAL TESTING:
RADIOLOGICAL:
DCBE
CTC
ENDOSCOPIC:
Flexible Sigmoidoscopy
Colonoscopy
CRC Screening Guidelines
2008 ACS-MSTF-ACR
Early Detection / Prevention:
Colonoscopy
q10 yrs
CTC
q5 yrs (Colonoscopy if >6 mm)
FSIG
q5 yrs
DCBE
q5 yrs
Early Detection:
gFOBT
q1 yr
iFOBT
q1 yr
sDNA
q?
2008 USPSTF:
FOBT q1 yr
FSIG q5 yrs + FOBT q3 yrs
Colonoscopy q10 yrs
Colon Polyps
Non-Neoplastic Polyps
Hyperplastic
Mucosal
Inflammatory pseudopolyps
Submucosal (lipomas, fibromas, GIST)
Hamartomatous
Juvenile polyposis
Peutz-Jeghers
Cronkhite-Canada syndrome
Neoplastic Polyps
Serrated Polyps
Adenomatous Polyps
Colon Cancer-Post Curative surgery
Non-Neoplastic Polyps
1. Hyperplastic polyp
2. Inflammatory pseudopolyps
3. Submucosal (lipomas, fibromas, GIST)
Non-Neoplastic Polyps
HAMARTOMAS
Juvenile Polyposis Syndrome
Peutz-Jeghers Syndrome
Cronkhite-Canada Syndrome
Neoplastic Polyps
Serrated Polyps
Adenomatous/Tubulovillous Polyps
Serrated Polyps
Hyperplastic Polyps (non-neoplastic)
Typically <5mm in RS
No increase in CRC
No increase in proximal neoplasia
If large > 10mm or proximal
precursor to SSA/P & progression to CRC
increased risk of synchronous advanced adenoma & multiple small
adenomas
increased risk of metachronous adenomas
Serrated Polyposis Syndrome (SPS)
WHO Criteria:
> 5 serrated proximal colon (> 2 @ > 10mm)
> 1 serrated proximal colon + FH of SPS
> 20 serrated polyps
Annual colonoscopy recommended (increased risk CRC)
Serrated Polyps
Sessile Serrated Adenoma/Polyp (SSA/P)
Typically in proximal colon
Typically lack classic dysplasia
Foci of classic DYSPLASIA & foci CANCER can occur
Traditional Serrated Adenoma (TSA)
Typically in rectosigmoid
Diffuse but mild DYSPLASIA
SSA/Ps & TSAs = Significant malignant potential
Manage like adenomas
Sessile w indistinct borders (must ensure complete excision)
Thought to disproportionately cause INTERVAL CANCERS
Adenomatous Polyps
⅔ of all polyps
>95% CRC arises from adenomas; <5% adenomas lead to CRC
Prevalence:
30% at baseline (30-50% will have synchronous)
4% Advanced adenoma at baseline (8% > age 65)
Advanced Adenomas: > 10 mm / HGD / Villous features
FOCAL CANCER RISK:
METACHRONOUS ADENOMA RISK:
Villous histology
# of polyps (> 3 )
Polyp size
Lifetime polyps
HGD
Polyp size (20% when > 20 mm)
Surveillance Guidelines
2012 USMSTF (Endorsed by AGA, ASGE, ACG, ACS, & ACR)
Risk Stratification
LRAs:
1-2 TA <10mm
HRAs:
Villous histology
HGD
Adenoma >10 mm
>3 small adenomas
Baseline: NO POLYPS
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
STUDY
10 yrs
Moderate
n
5 yr AA (%)
2007 VA Co-Op
291
2.4
2008 Imperiale
1256
1.3
2009 Leung
370
1.4
2010 Brenner
115
4.4
2010 US Vets
86
7
2011 Korean
1242
2
2009 PLCOC
318
5.3 (@6-7 yrs)
Advanced Adenomas @5 yrs: 1.3-2.4% (baseline 4-10%)
CAVEAT: FDR w CRC <age 60
5yr interval
Concern for 10yr interval:
3 Canadian population studies:
9% of CRC are INTERVAL cancers
most occur 1-5 yrs from baseline exam
Importance of HIGH QUALITY examination
Baseline: Distal HPs <10mm
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
10 yrs
Moderate
HPs are very common:
Polyp Size (mm)
% HPs
1-5
50
6-9
27.9
>10 mm
13.7
benign lesions
no increased synchronous / metachronous adenomas
Baseline: 1-2 Adenomas <10mm
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
STUDY
5-10 yrs
Moderate
n
5yr AA (%)
2007 VA Co-Op
291
4.6
2008 PPT
1905
5
2010 US Vets
86
5.2
2011 Korean
1242
2.4
2009 PLCOC
318
5.3 (@6-7 yrs)
Baseline AA: 4-10%
Best to do 5-year interval
Baseline: 3-10 Adenomas <10mm
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
3 yrs
Moderate
2009 NCI Pooling Study
%AA @3-5yrs
26
19.5
13
6.5
0
2
1
3
4
5
# Polyps
Surveillance Guidelines
2012 USMSTF
Risk Stratification
LRAs:
HRAs:
1-2 TA <10mm
Villous histology
HGD
Adenoma >10 mm
>3 small adenomas
2010 British Gastro Society:
LRAs
1-2 TA <10mm
IRAs
HRAs
Adenoma >10 mm
>5 small adenomas
3-4 small adenomas
>3 adenomas w 1 >10mm
Baseline: >10 Adenomas <10mm
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
<3 yrs
Moderate
Consider 1yr colonoscopy
Consider HEREDITARY syndromes
Baseline: >1 Adenoma >10mm, or
Adenoma w villous features, or HGD
2012 USMSTF
RECOMMENDATION:
3 yrs
QUALITY of EVIDENCE: High (size) / Mod (histo)
STUDY
Feature
Surveillance AA (%)
10-19 mm
15.9
>20 mm
19.3
>10 mm
15.5
2009 NCI Pooling Study (3-5 yrs)
TVA
16.8
2007 VA Co-Op (5 yrs)
TVA
16.1
2009 NCI Pooling Study (3-5 yrs)
2007 VA Co-Op (5 yrs)
LARGE POLYPS:
If complete excision is questioned...early f/u recommended
Risk of HGD does not appear independent:
Size &
Histology
Baseline: SERRATED POLYPS
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
RISK FACTORS:
3-5 yrs
Low
SIZE: >10mm
HISTO:
Sessile serrated > HP
SSA/P w dysplasia > SSA/P w/o dysplasia
Location: Prox SC > distal SC
Recommendations:
SSA/P > 10mm
SSA/P w dysplasia
HRA-like: 3 yrs
Traditional serrated adenomas
SSA/P <10mm w/o dysplasia
LRA-like: 5 yrs
2nd Surveillance Guidelines
2012 USMSTF
Baseline
LRA
HRA
** LRA @ Baseline
Neg 1st colon
Surveillance
1st
2nd
Neg
10 yrs **
LRA
5 yrs
HRA
3 yrs
Neg
5 yrs
LRA
5 yrs
HRA
3 yrs
2.8 - 4.9% AA @ 3-5 yrs
Consider 5yr surveillance rather than 10
Colonoscopy Quality Indicators
Adenoma detection rate
Avg. risk: 30.2% (22-58%)
Heitman SJ, Clin Gastro Hep 2009
40% w High Definition Colonoscopes
Cecal intubation rate
(Adherence to surveillance guidelines)
Overutilization
Underutilization
Monitoring of bowel preparation
Inadequate -----> 35% adenoma & 36% AA miss rate at 1 yr
USMSTF:
Inadequate: repeat < 1yr
Fair but adequate: repeat 5 yrs (OK to detect >5 mm)
Colonoscopy: Imperfect Gold
Std
Back-to-back colonoscopy in 183 patients
Rex DK, Gastroenterol 1997
Polyp Size (mm)
Miss Rate (%)
<5
27
6-9
13
>10 mm
6
CTC trials: Segmental
Unblinding
Polyp Size (mm)
Miss Rate (%)
>10 mm
12-17
Interval Cancers
Majority due to missed lesions
Directly related to quality of exam
Incomplete polyp resection
19-27% occur in same colon segment
polyps >20 mm ---> 18% residual adenoma
Biologically different
More proximal
Increased microsatellite instability (mismatch repair)
CIMP +ve (CpG Island Methylator Phenotype)
? significant role from SSA/P
Stool DNA Testing
Approved 2014
Earlier test withdrawn from mrkt
Immunochemical assay (iFOBT) added
Molecular assay for DNA mutations & methylation biomarkers
COLOGUARD
Detects 92% of CRC
Detects 42% adenomas
Contraindications:
Hx of ADENOMAS, CRC
FHx of CRC
Diarrhea, hemorrhoids, fissures
2014 FIT v sDNA v Colonoscopy
NNTT (find 1 CRC):
FIT
208
sDNA
166
Colonoscopy
154
Stool DNA Testing
“Patients with a negative Gologuard test result
should be advised to continue participating in a
colorectal cancer screening program with another
recommended screening method”
Cologuard +ve ---> COLONOSCOPY
Cologuard -ve ---> COLONOSCOPY
Ideal test for patients fearful of
colonoscopy!
CT Colonography
Nearly as sensitive as colonoscopy
Still need bowel preparation
Fecal tagging techniques being developed
Need colonoscopy if positive
Extracolonic findings can lead to futile work-up
Major Disadvantages:
Requires radiation for a screening test
Not covered by insurance
Surveillance for Post Curative Surgery
Colon Cancer
2012 USMSTF
RECOMMENDATION:
QUALITY of EVIDENCE:
1 year
Moderate
Colonoscopy 1 yr, 3 yrs, 5 yrs post
surgery
Rectal Cancer: EUS with Sigmoidoscopy 1 yr, 3
yrs, 5 yrs post surgery
Summary
10 yr colonoscopy
NEGATIVE x2 (including distal HPs)
Age 40-50 w NEGATIVE colon for other cause
5 yr colonoscopy
NEGATIVE x1
NEGATIVE x2 w FDR age <60
1-2 small adenomas
SSA/P < 10 mm w/o dyspl
3 yr colonoscopy
3-5 small adenomas
HRAs (adenoma > 10mm, HGD, Villous features)
SSA/P > 10 mm, SSA/P w dyspl, TSAs
1 yr colonoscopy
> 5 small adenomas
> 3 adenomas w > 1 @ 10 mm+
Malignant polyp
< 1 yr colonoscopy
Inadequate preparation
Large flat adenomas w HGD
Large flat adenoma or SSA/P w incomplete resection