470 likes | 654 Views
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*. Men 675,300. Men 675,300. Women 658,800. Women 658,800. Prostate 222,849 Lung/bronchus 94,542
E N D
Colorectal CancerWhen to refer ? Dr Devinder Singh Bansi BM FRCP DM Consultant Gastroenterologist Imperial College London 29.09.2011
2003 Estimated US Cancer Cases* Men675,300 Men675,300 Women658,800 Women658,800 Prostate 222,849 Lung/bronchus 94,542 Colon/rectum 74,283 Urinary bladder 40,518 Melanoma of 27,012skin Non-Hodgkin 27,012lymphoma 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.
2003 Estimated US Cancer Deaths* Men285,900 Women270,600 Lung/bronchus 88,629 Prostate 28,590 Colon & rectum 28,590 Pancreas 14,295 Non-Hodgkin 11,436lymphoma Leukemia 11,436 Esophagus 11,436 Liver/intrahepatic 8,577bile 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.
Colorectal cancerSome 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
Bowel cancer -UK malesfemales New cases (2008) 22,097 17,894 Rate/100,00 pop. 58.5 37.8 5 yr survival (2001-6) 50% 51% (colon cancer) 5 yr survival 92001-6) 51% 55% (rectal cancer)
How Does Colorectal Cancer Develop? Janne PA, Mayer RJ. N Engl J Med 2000;342:1960.
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
Colorectal cancer:Symptoms may be site specific • Rectal cancer • 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
Colorectal cancer:Distribution of disease • Rectum 27% • Rectosigmoid junction 7% • Sigmoid colon 20% • Descending Colon 3% • Splenic flexure 2% • Transverse Colon 5% • Hepatic Flexure 3% • Ascending Colon 7% • Caecum 14% • Appendix 1% • Other and unspecified 9%
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. 60-70% report rectal bleeding as a principal symptom
Colorectal cancer:The significance of age • Only 1% of all CRC occur in individuals <40 yrs • 4% CRC occur in age range 40-50 yrs • Risk rises more rapidly >50 yrs • BUT ‘No one is too young to have bowel cancer’
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)
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 !
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 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 • 160 GP referral letters for suspected CRC available for study
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
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 69.8 69.3 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)
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 ?!
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
Is Colorectal Cancer Preventable? YES! • Screening • Chemoprevention
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).
Screening For Colon Cancer SAVES LIVES!!! MortalityTest Reduction Fecal occult blood testing 33% Flexible sigmoidoscopy 66% (in portion of colon examined) FOBT + flexible sigmoidoscopy 43% (compared to sigmoidoscopy alone) Colonoscopy ~76-90% (after initial screening and polypectomy)
Colorectal cancer screeningFirst 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: • 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 • 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 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.
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
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
Future techniques for colorectal cancer screening • Stool DNA testing • Capsule endoscopy (Givens capsule) • CT colography (virtual colonoscopy)
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
Videocapsule Lymphoma
CT Colography Colon Polyp
CT Colography Colon Polyp
CT Colography Colon Cancer
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
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