Transcript Document

Colorectal Cancer
When to refer ?
Dr Devinder Singh Bansi BM FRCP DM
Consultant Gastroenterologist
Imperial College
London
29.09.2011
2003 Estimated US Cancer Cases*
Prostate
222,849
Men
Men
675,300
675,300
Women
658,800
210,816 Breast
Lung/bronchus
94,542
79,056 Lung/bronchus
Colon/rectum
74,283
72,468 Colon & rectum
Urinary bladder 40,518
39,528 Uterine corpus
Melanoma of
skin
27,012
26,352 Ovary
Non-Hodgkin
lymphoma
27,012
26,352 Non-Hodgkin
lymphoma
Kidney
20,259
19,764 Melanoma of
skin
Oral cavity
20,259
19,764 Thyroid
Leukemia
20,259
13,176 Pancreas
Pancreas
13,506
13,176 Urinary bladder
All other sites
114,801
62,238 All other sites
ONS=Other nervous system.
*Excludes basal and squamous cell skin cancers and in situ carcinomas except urinary bladder.
Source: American Cancer Society, 2003.
2003 Estimated US Cancer Deaths*
Lung/bronchus
88,629
Prostate
28,590
Men
285,900
Women
270,600
67,650 Lung/bronchus
40,590 Breast
Colon & rectum 28,590
29,766 Colon & rectum
Pancreas
14,295
16,236 Pancreas
Non-Hodgkin
lymphoma
11,436
13,530 Ovary
Leukemia
11,436
10,824 Non-Hodgkin
lymphoma
Esophagus
11,436
10,824 Leukemia
Liver/intrahepatic 8,577
bile duct
Urinary bladder
8,577
Kidney
8,577
All other sites
8,118
Uterine corpus
5,412
Brain/ONS
5,412
Multiple myeloma
62,238 All other sites
62,898
ONS=Other nervous system.
*Excludes basal and squamous cell skin cancers and in situ carcinomas except urinary bladder.
Source: American Cancer Society, 2003.
Colorectal cancer
Some useful statistics
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Approx 40,000 cases diagnosed in UK in 2008
(110 people/day)
>80% in people aged 60 or over
Incidence relatively stable in last 10 years
5 yr survival rates doubled in last 40 yrs
STILL REMAINS 2nd most common cause of
death from malignant disease in UK
Bowel cancer -UK
males
females
New cases (2008)
22,097
17,894
Rate/100,00 pop.
58.5
37.8
5 yr survival (2001-6)
(colon cancer)
50%
51%
5 yr survival 92001-6)
(rectal cancer)
51%
55%
Colon Polyp
Colon Cancer
How Does Colorectal Cancer Develop?
Janne PA, Mayer RJ. N Engl J Med 2000;342:1960.
Colorectal cancer:
At a local level
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Individual GP would expect to diagnose only 1-2 cases
per year
Bowel symptoms are common in the general
population
Increased number of ‘worried well’ patients
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‘well publicised large bowel cancer awareness campaigns
How to select patients with large bowel symptoms who
should be sent for urgent investigation ?
A selection policy will inevitably lead to missed cases
and potential litigation
Colorectal cancer:
Symptoms may be site specific
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Rectal cancer
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Sigmoid cancer
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Classically tenesmus/rectal bleeding
Altered bowel habit, with tendency to looser stool
Right sided cancers
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No or few GI symptoms
Palpable mass or anaemia
Colorectal cancer:
Distribution of disease
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Rectum
Rectosigmoid junction
Sigmoid colon
Descending Colon
Splenic flexure
Transverse Colon
Hepatic Flexure
Ascending Colon
Caecum
Appendix
Other and unspecified
27%
7%
20%
3%
2%
5%
3%
7%
14%
1%
9%
Colorectal cancer:
The significance of rectal bleeding
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Arguably the most diagnostically difficult
symptom for GPs
Common and, in isolation, only rarely caused
by bowel cancer
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Only 3% of 1000 pts with only rectal bleeding sent
to hospital for investigation
Conversely, of all patients with left-sided
CRC, approx. 60-70% report rectal bleeding
as a principal symptom
Colorectal cancer:
The significance of age
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Only 1% of all CRC occur in individuals <40
yrs
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4% CRC occur in age range 40-50 yrs
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Risk rises more rapidly >50 yrs
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BUT
‘No one is too young to have bowel cancer’
Colorectal cancer:
High Risk Individuals
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Anaemia or palpable mass (any age)
>50 yrs with CIBH >6 weeks to looser stool
and/or increased stool frequency
Rectal bleeding with CIBH (all ages)
>50 with rectal bleeding
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The danger of not investigating this group, even if it appears to be
from benign ano-rectal causes, is that the patient may be falsely
reassured and not represent when symptoms persist or change
Patients of any age with symptoms and a
strong FH of CRC
Iron deficiency anaemia without an obvious
cause (all ages)
Other symptomatic groups
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<40 with symptoms of CIBH ?
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<40 with symptoms of bright red bleeding but
no CIBH ?
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May be acceptable to adopt wait and see approach for 6
weeks as in most cases symptoms will be self-limiting
However, important to have arrangements in place to review
the patient and investigate if symptoms persist
Patients with ‘bloody diarrhoea’ may have IBD so should be
referred urgently
Do not require urgent referral but a definitive diagnosis
should be made
Rectal examination/sigmoidoscopy as minimum.
Possibly watch and wait for 6 weeks but may be pressure to
refer to specialist
If in doubt: REFER !
Referral of suspected Colorectal Cancer:
Have guidelines made a difference ?
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British Journal of General Practice Aug 2004
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Exeter Primary Care Trust
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All 361 cases of CRC (population 132000) from
Jan 1998- Sept 2002 identified as part of a study
examining GP records for pre-diagnostic clues to
a malignant diagnosis
200 cases randomly selected
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160 GP referral letters for suspected CRC
available for study
Features of importance in CRC identified by GPs
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Rectal bleeding
CIBH (usually diarrhoea)
Weight loss
Iron deficiciency anaemia
Abdominal mass
History of IBD
History of colorectal polyps or signs of CRC on
previous investigation
FH of CRC
GPs opinion that patient has CRC
Mucus per rectum
Abdominal pain
Referrals made before and after the introduction
of national cancer guidelines for CRC
June 1997-June 2000
Mean age
Men
Patients referred urgently
Satisfied criteria for urgent
Referral
Satisfied criteria and had
Urgent referral
Did not satisfy criteria
And had urgent referral
Duke’s A or B cancer
June 2000-Sept 2002
n= 92
n=65
69.8
51(55%)
38 (41)
69.3
32 (49)
32 (49)
64/89 (72)
48/64 (75)
35/64 (55)
27/48 (56)
2/25( 8)
49/87 (56)
5/16 (31)
31/50 (62)
Lessons ?
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Positive predictive value of symptomatic guidelines
for diagnosing CRC is only 10%
Significant number of patients diagnosed outside the
‘stream-lined’ referral route eg via A/E, other
specialties
Little increase in numbers of urgent referrals may
represent the fact that many colorectal cancers do
not meet the criteria for urgent referral.
Urgent referrals outside the guidelines may be
appropriate
WHAT TO DO ?!
Referring Patients for Suspected Colorectal Cancer:
Common reasons for litigation
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Failure to refer a patient with high-risk large bowel
symptoms and so provide inappropriate reassurance
Failure to do a rectal examination in a patient who
subsequently proves to have a rectal cancer
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In the event that a practitioner has decided upon urgent
referral to a specialist , a rectal examination is not necessary
In the case of a ‘watch and see ‘ policy, better to do a rectal
examination since the majority of expert witnesses tend to be
of the ‘old school’ !!
Defence based on ‘lack of causative consequences’
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Demonstration of disseminated disease which would
therefore not effect prognosis
Survival by Dukes Stage
Symptoms of Colorectal Cancer
Time Course
Symptoms
Findings
Early
None
None
Occult blood in stool
Mid
Rectal bleeding
Change in bowel
habits
Rectal mass
Blood in stool
Late
Fatigue
Anemia
Abdominal pain
Weight loss
Abdominal mass
Bowel obstruction
Staging of Colorectal Cancer
Frequency of Colorectal Cancer by
Dukes Stage
Treatment of Colorectal Cancer
by Stage
Is Colorectal Cancer Preventable?
YES!
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Screening
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Chemoprevention
Screening Techniques for Colorectal
Cancer
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Fecal occult blood test (FOBT) every year, or
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Flexible sigmoidoscopy every 5 years,or
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A fecal occult blood test every year plus flexible
sigmoidoscopy every 5 years (recommended by
the American Cancer Society), or
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Colonoscopy every 10 years (recommended by
the American College of Gastroenterology).
Screening For Colon Cancer
SAVES LIVES!!!
Test
Mortality
Reduction
Fecal occult blood testing
33%
Flexible sigmoidoscopy
66%
(in portion of colon examined)
FOBT + flexible sigmoidoscopy
43%
(compared to sigmoidoscopy alone)
Colonoscopy
(after initial screening and polypectomy)
~76-90%
Colorectal cancer screening
First assess RISK
AVERAGE RISK INDIVIDUAL
• All patients age 50 years and older, the
asymptomatic general population
HIGH RISK
• Personal history – polyp or cancer
• Family history – polyp or cancer in first
degree relatives
Why aren’t more people screened for
colon cancer?
Reasons for refusal of fecal occult blood testing
• Fear of further testing and surgery
• Feeling well
• Unpleasantness of stool collection procedure
But:
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Strongest predictor of whether a patient will be
screened = physician encouragement
Hynam et al. J Epidemiol Comm Health 1995;49:84
Mandelson et al. Am J Prevent Med 2000;19:149
Fecal Occult Blood Testing
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Examination of stool for occult (“hidden”)
blood
Can detect one teaspoon or less of blood in a
bowel movement
Uses chemical reaction between blood and
reagent
FOBT improves survival
Years after diagnosis
Trends in FOBT, 1997-2001
Prevalence (%)
30
25
20
1997
1999
2001
15
10
5
0
Total
Men
Women
Less than High High School Some college
School
graduate
or greater
Source: Behavioral Risk Factor Surveillance System, 1996-1997, 1999, 2001, National Center for Chronic Disease
Prevention and Health Promotion, Centers for Disease Control and Prevention and Prevention, 1999, 2000, 2002.
Site Distribution
Flexible sigmoidoscopy
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Pros
• May be done in office
• Inexpensive, cost-effective
• Reduces deaths from rectal cancer
• Easier bowel preparation, usually done without
sedation
Cons
• Detects only half of polyps
• Misses 40-50% of cancers located beyond the
view of the sigmoidoscope
• Often limited by discomfort, poor bowel
preparation
Selby et al N Engl J Med 1992; 336:653
Newcomb et al. JNCI 1992; 84:1572
Rex et al. Gastrointest Endosc 1999; 99:727
Stewart et al Aust NZ J Surg 1999; 69:2
Painter et al Endoscopy 1999; 3:269
Colonoscopy
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Pros
• Examines entire colon
• Removal of polyps performed at time of exam
• Well-tolerated with sedation
• Easier bowel preparation, usually done without
sedation
Cons
• Expensive
• Risk of perforation, bleeding low but not negligible
• Requires high level of training to perform
• Miss rate of polyps < 1 cm ~25%, > 1 cm ~5%
Rex et al. Gastroenterology 1997; 112:24-8
Postic et al. Am J Gastroenterol 2002; 97:3182-5
Chemopreventive agents
Fiber
Not effective
Aspirin
May be effective
NSAIDs (ibuprofen, etc)
Probably effective
Vitamin E, vitamin C, beta Not effective
carotene
Folate
Effective if obtained in
diet
Calcium
Effective
Estrogen
Effective, but has other
problems
Future techniques for colorectal
cancer screening
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Stool DNA testing
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Capsule endoscopy (Givens capsule)
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CT colography (virtual colonoscopy)
Fecal Testing for Gene Mutations
Fecal Testing for Gene Mutations
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Pros
• No sedation or preparation necessary
• Home-based (sample mailed to physician)
• No risk
Cons
• Current tests not very good (~50% of cancers
missed)
• Cost
• Frequency of exam unknown
• Not therapeutic
• Not covered by insurance
Videocapsule
Videocapsule
Lymphoma
CT Colography
Colon Polyp
CT Colography
Colon Polyp
CT Colography
Colon Cancer
CT Colography
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Pros
• No sedation necessary
• 20 min procedure vs. 25 min for colonoscopy
• Low risk
• Extracolonic lesions may be detected
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Cons
• Preparation (residual fluid cannot be aspirated)
• Air insufflation
• Cost (? need for more frequent exams)
• Radiation dose (similar to barium enema)
• Not therapeutic
• Not covered by insurance
Summary
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Colorectal cancer is the third most common
cancer and cause of cancer death in the U.S.
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Chemopreventive agents have modest
benefit in average risk individuals
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Screening for colorectal cancer saves lives!
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Patient and physician compliance with
screening is poor