1. Colorectal Cancer When to refer ?
Dr Devinder Singh Bansi BM FRCP DM
Consultant Gastroenterologist
Imperial College
London

2. 2003 Estimated US Cancer Cases*
Men 675,300
Men 675,300
Women 658,800
Women 658,800
Prostate 222,849
Lung/bronchus 94,542
Colon/rectum 74,283
Urinary bladder 40,518
Melanoma of 27,012 skin
Non-Hodgkin 27,012 lymphoma
Kidney 20,259
Oral cavity 20,259
Leukemia 20,259
Pancreas 13,506
All other sites 114,801
210,816 Breast
79,056 Lung/bronchus
72,468 Colon & rectum
39,528 Uterine corpus
26,352 Ovary
26,352 Non-Hodgkin lymphoma
19,764 Melanoma of skin
19,764 Thyroid
13,176 Pancreas
13,176 Urinary bladder
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.

3. 2003 Estimated US Cancer Deaths*
Men 285,900
Women 270,600
Lung/bronchus 88,629
Prostate 28,590
Colon & rectum 28,590
Pancreas 14,295
Non-Hodgkin 11,436 lymphoma
Leukemia 11,436
Esophagus 11,436
Liver/intrahepatic 8,577 bile duct
Urinary bladder 8,577
Kidney 8,577
All other sites 62,898
67,650 Lung/bronchus
40,590 Breast
29,766 Colon & rectum
16,236 Pancreas
13,530 Ovary
10,824 Non-Hodgkin lymphoma
10,824 Leukemia
8,118 Uterine corpus
5,412 Brain/ONS
5,412 Multiple myeloma
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.

4. Colorectal cancer Some useful statistics
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

5. Bowel cancer -UK
males females New cases (2008) 22,097 17,894 Rate/100,00 pop yr survival (2001-6) 50% 51% (colon cancer) 5 yr survival ) 51% 55% (rectal cancer)

6. Colon Polyp

7. Colon Cancer

8. How Does Colorectal Cancer Develop?
Janne PA, Mayer RJ. N Engl J Med 2000;342:1960.

9. Colorectal cancer: At a local level
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
‘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

10. Colorectal cancer: Symptoms may be site specific
Classically tenesmus/rectal bleeding
Sigmoid cancer
Altered bowel habit, with tendency to looser stool
Right sided cancers
No or few GI symptoms
Palpable mass or anaemia

11. Colorectal cancer: Distribution of disease
Rectum %
Rectosigmoid junction 7%
Sigmoid colon 20%
Descending Colon 3%
Splenic flexure 2%
Transverse Colon 5%
Hepatic Flexure 3%
Ascending Colon 7%
Caecum %
Appendix 1%
Other and unspecified 9%

12. Colorectal cancer: The significance of rectal bleeding
Arguably the most diagnostically difficult symptom for GPs
Common and, in isolation, only rarely caused by bowel cancer
Only 3% of 1000 pts with only rectal bleeding sent to hospital for investigation
Conversely, of all patients with left-sided CRC, approx % report rectal bleeding as a principal symptom

13. Colorectal cancer: The significance of age
Only 1% of all CRC occur in individuals <40 yrs
4% CRC occur in age range yrs
Risk rises more rapidly >50 yrs
BUT
‘No one is too young to have bowel cancer’

14. Colorectal cancer: High Risk Individuals
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
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)

15. Other symptomatic groups
<40 with symptoms of CIBH ?
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
<40 with symptoms of bright red bleeding but no CIBH ?
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 !

16. British Journal of General Practice Aug 2004
Referral of suspected Colorectal Cancer: Have guidelines made a difference ?
British Journal of General Practice Aug 2004
Exeter Primary Care Trust
All 361 cases of CRC (population ) from Jan Sept 2002 identified as part of a study examining GP records for pre-diagnostic clues to a malignant diagnosis
200 cases randomly selected
160 GP referral letters for suspected CRC available for study

17. Features of importance in CRC identified by GPs
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

18. Referrals made before and after the introduction of national cancer guidelines for CRC
June 1997-June 2000 June 2000-Sept 2002
n= 92 n=65
Mean age
Men 51(55%) 32 (49)
Patients referred urgently 38 (41) 32 (49)
Satisfied criteria for urgent
Referral 64/89 (72) 48/64 (75)
Satisfied criteria and had
Urgent referral 35/64 (55) 27/48 (56)
Did not satisfy criteria
And had urgent referral 2/25( 8) 5/16 (31)
Duke’s A or B cancer 49/87 (56) 31/50 (62)

19. Lessons ?
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 ?!

20. Referring Patients for Suspected Colorectal Cancer: Common reasons for litigation
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
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’
Demonstration of disseminated disease which would therefore not effect prognosis

21. Survival by Dukes Stage

22. Symptoms of Colorectal Cancer
Time Course
Symptoms
Findings
Early
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

23. Staging of Colorectal Cancer

24. Frequency of Colorectal Cancer by Dukes Stage

25. Treatment of Colorectal Cancer by Stage

26. Is Colorectal Cancer Preventable?
YES!
Screening
Chemoprevention

27. Screening Techniques for Colorectal Cancer
Fecal occult blood test (FOBT) every year, or
Flexible sigmoidoscopy every 5 years,or
A fecal occult blood test every year plus flexible sigmoidoscopy every 5 years (recommended by the American Cancer Society), or
Colonoscopy every 10 years (recommended by the American College of Gastroenterology).

28. Screening For Colon Cancer SAVES LIVES!!!
Mortality Test Reduction
Fecal occult blood testing %
Flexible sigmoidoscopy %
(in portion of colon examined)
FOBT + flexible sigmoidoscopy %
(compared to sigmoidoscopy alone)
Colonoscopy ~76-90%
(after initial screening and polypectomy)

29. 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 4

30. 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:
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

31. Fecal Occult Blood Testing
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

32. FOBT improves survival
Years after diagnosis

33. Trends in FOBT,
Source: Behavioral Risk Factor Surveillance System, , 1999, 2001, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention and Prevention, 1999, 2000, 2002.

34. Site Distribution 17. Site Distribution
At one time, conventional wisdom held that half of all colorectal tumors could be reached with the examining finger, or at least the rigid sigmoidoscope. This reflects the distal predominance of colorectal cancer, whose distribution roughly corresponds to that of adenomas. A gradual shift toward a more proximal distribution may be occurring. Whether this is due to improved detection of right-sided tumors, to a change in dietary carcinogen-related exposure of the mucosa, or to other factors, is unknown.
• Vukasin AP, Ballantyne GH, Flannery JT, et al: Increasing incidence of cecal and sigmoid carcinoma. Data from the Connecticut Tumor Registry. Cancer, 66:2442-9, 1990.
• Shinya Y, Wolff WI: Morphhology, anatomic discribution, and cancer potential of colonic polyps. Ann Surg, 190:679-83, 1979.

35. Flexible sigmoidoscopy
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 Stewart et al Aust NZ J Surg 1999; 69:2
Newcomb et al. JNCI 1992; 84:1572 Painter et al Endoscopy 1999; 3:269
Rex et al. Gastrointest Endosc 1999; 99:727

36. Colonoscopy 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

37. Chemopreventive agents
Fiber
Not effective
Aspirin
May be effective
NSAIDs (ibuprofen, etc)
Probably effective
Vitamin E, vitamin C, beta carotene
Folate
Effective if obtained in diet
Calcium
Effective
Estrogen
Effective, but has other problems

38. Future techniques for colorectal cancer screening
Stool DNA testing
Capsule endoscopy (Givens capsule)
CT colography (virtual colonoscopy)

39. Fecal Testing for Gene Mutations

40. Fecal Testing for Gene Mutations
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

41. Videocapsule

42. Videocapsule
Lymphoma

43. CT Colography
Colon Polyp

44. CT Colography
Colon Polyp

45. CT Colography
Colon Cancer

46. CT Colography Pros No sedation necessary
20 min procedure vs. 25 min for colonoscopy
Low risk
Extracolonic lesions may be detected
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

47. Summary
Colorectal cancer is the third most common cancer and cause of cancer death in the U.S.
Chemopreventive agents have modest benefit in average risk individuals
Screening for colorectal cancer saves lives!
Patient and physician compliance with screening is poor