Bowel cancer screening and prevention

Transcription

1 Bowel cancer screening and prevention

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3 Cancer Incidence and Mortality Victoria 2012 Number Incidences = 29,387 Mortality = 10,780 Incidence Mortality Prostate Breast Bowel Lung Cancer Type Victorian Cancer Registry 2012

4 New cases and deaths in 2012 for the leading cancers in Victorian men 6,000 New cases/deaths in ,000 4,000 3,000 2,000 1,000 0 Type of Cancer Prostate Bowel Lung Melanoma New cases Deaths Victorian Cancer Registry 2012

5 New cases and deaths in 2011 for the leading cancers in Victorian women 3, New cases Deaths New cases/deaths in ,000 1, Breast Bowel Lung Melanoma Type of Cancer Victorian Cancer Registry 2012

6 Signs and symptoms CRC Most early bowel cancers don t produce obvious signs or symptoms Symptoms often typical of several common conditions Most common presenting symptoms: - Bleeding from the rectum, mixed with or separate from faeces - Persistent change in bowel habit - Symptoms of anaemia - Colicky lower abdominal pain - Unexplained weight loss

7 Pathogenesis of colorectal cancer Polyp on long stalk Flat adenoma Adenomatous polyp that grows inside large bowel Slow growing (10+ years), many never progress Benign adenomas may become malignant over time Usually removed when observed through colonoscopy

8 Risk factors CRC Non-modifiable: aged 50 years+ inflammatory bowel disease strong family history of bowel cancer Modifiable: diet obesity smoking high alcohol intake physical inactivity

9 Familial risk factors for CRC

10 Familial Adenomatous Polyposis (FAP) Usually due to a mutation in one of two copies of a tumour suppressor gene Hundreds of adenomas throughout the colon and rectum - can develop into cancer, often at early age - consider prophylactic surgery May appear as teenager/ young adult

11 Hereditary Non-Polyposis Colorectal Cancer (HNPCC) Lynch Syndrome Inherited mutation in a copy of one of a group of DNA mismatch repair genes (MMR) Usually strong family history of colorectal cancer - early age onset, usual diagnosis before age 50 - multiple colorectal cancers Association with endometrial, ovarian etc cancers

12 Potentially high risk (FAP, HNPCC) Three or more 1 st degree relatives or a combination of 1degree/2 degree relatives on the same side of the family Two or more 1degree/2degree relatives on the same side of the family plus any of the following high risk features: - Multiple bowel cancers in a family member - Bowel cancer before the age of 50 - Family member who has/had an HNPCC related cancer At least one 1degree/2degreee relative with suspected FAP (i.e. hundreds of polyps in the large bowel) Member of a family identified with a high risk gene mutation

13 Evidence-based guidelines NHMRC and RACGP recommend Faecal Occult Blood Testing every two years for all men and women aged 50 and older It is important for GPs to remind patients to present if they develop signs or symptoms i.e. population screening may be inappropriate for these patients NHMRC Guidelines

14 National Bowel Cancer Screening Program (NBCSP)

15 Benefits of screening with FOBT Can detect CRC at early stage, with 90% chance of curing it Reduces the risk of dying from bowel cancer by at least 15-33% Most bowel cancers take up to10+ years to develop, so having an FOBT every 2 years is an appropriate interval Detects both pre-cancerous polyps as well as adenomatous polyps that may develop into cancer over time Bowel cancer has a defined natural history that makes screening by ifobt appropriate for early detection ifobt has an 85-90% sensitivity for lower GI bleeding FOBT can be done in the privacy of the home

16 Limitations of screening with FOBT Positive FOBT requires further investigation, usually colonoscopy. Most people who have a colonoscopy will not have cancer. Although rare, there are risks associated with colonoscopy. Not all bowel cancers detected by screening can be successfully treated Participants may be anxious waiting for results; however, NBCSP patients with a positive FOBT are fast-tracked to investigative colonoscopy The test involves faecal testing which some find unpleasant A negative result is not 100% conclusive because some bowel cancers don't bleed, or do so intermittently

17 Types of FOBT 1. Guaiac (pseudoperoxidase activity of haem) Cons: Dietary changes e.g. no red meat, eliminate certain vegetables Medication changes e.g. no Vit C, aspirin, iron supplements Not specific to human haem 50% sensitivity for bowel cancer Subjective visual result reading Pros: Low cost Accessibility

18 Types of FOBT, cont. 2. Immunochemical tests (antibodies to human globin) Pros: Cons: No diet or medication changes Greater cost 80-90% sensitivity Specific Limited for availability lower G-I for bleeding some programs Easy, hygienic, user-friendly Immediate stabilisation of Hb Automated lab processing High throughput for population screening Test recommended by national guidelines Cons: Greater cost Limited availability for some programs

19 Correct storage for ifobt Complete and post the test within 10 days of collecting the first sample Samples should be stored in a cool dry place, preferably between 2-10 degrees Can be stored in the refrigerator if necessary Avoid posting on hot days, or post the envelope in an indoors mail box, or post just prior to collection times

20 Positive FOBT i.e. low grade bleeding NBCSP (data from Qld public sector) FOBT positivity rate 7.7% PPVs for: - bowel cancer 4.3% - advanced adenoma 23% - non-advanced adenoma 25% i.e. 52% of people with a positive FOBT will have some sort of cancer or adenoma times more likelihood of finding bowel cancer with positive FOBT than with negative FOBT M. Appleyard et al (2011)

21 Referral for colonoscopy The patient should be referred for colonoscopy within four weeks if symptoms are highly suggestive of bowel cancer Ideally refer to a physician or surgeon who has Conjoint Committee recognition of their training in colonoscopy

22 Who should have a colonoscopy? Symptoms Strong Family History Past Bowel Cancer or AA Positive FOBT Targeted Colonoscopy

23 Why colonoscopy inappropriate for screening Colonoscopy: Low yield Lack of high level evidence for benefit outweighing harm Inappropriate for population screening of 5 million Australians Cost Patient inconvenience/ compliance Potential complications: - difficulties with preparation - anaesthetic complications - perforation of colon (1/ cases) - bleeding following procedure (1/500 cases) - death (1/10,000 cases) - ~ 5% are not completed

24 Colonoscopy reports what to look for Look Quality of bowel preparation Length of bowel examined and action to take if caecum could not be reached Withdrawal time Size, type, number and site of any adenomas or cancers Suggested repeat procedure interval Biopsy comments

25 NBCSP participation rates National Bowel Cancer Screening Program monitoring report: phase 2, July 2008-June 2011

26 Key Messages (Two ways to screen) NBCSP National Bowel Cancer Screening Program Screen in between FOBT kits provided by the government for males and females turning 50, 55, 60 and 65 years, who have no symptoms or family history of bowel cancer Can be done in the comfort and privacy of your own home. Involves taking samples from 2 bowel motions using a test kit Recommended every 2 years for all people aged 50+ who have no symptoms or family history of bowel cancer Can be done in the comfort and privacy of your own home. Involves taking samples from 2 bowel motions using a test kit Samples sent to the lab are tested for invisible blood in the bowel motion Samples sent to the lab are tested for invisible blood in the bowel motion If blood is found, further tests are needed. This is likely to be a colonoscopy If blood is found, further tests are needed. This is likely to be a colonoscopy Full biennial (every two years), implementation of the National Bowel Screening Program should be in place by Tests are available by visiting the cancer council website, Calling and from some pharmacies and health organisations.

27 Role of general practice Determine appropriateness of screening for individual patients Assess and manage high-risk individuals according to NHMRC guidelines Receive FOBT results where nominated by a participant Manage participants with a positive FOBT Notify NBCSP central registry of outcomes where applicable Recognise and assess individuals with symptoms that could be related to cancer, and in whom diagnostic investigations (rather than screening) are required Recommendation from a GP is shown to enhance participation rates in FOBT screening

28 Bowel screening intervals FOBT 2 yearly screening after age 50 recommended NHMRC, for all asymptomatic people The program should be fully implemented as biennial screening by 2020 NHMRC guidlines

29 Notification of the register of +ve results Important that GPs notify the register (on-line or hardcopy form) Allows for: Follow up of patients with a positive FOBT result Accurate data collection Which leads to: Accurate evaluation of the program Successful program = more lives saved

30 Follow-up of a +ve FOBT The Register will issue follow up letters and make follow up phone calls to participants and GPs if: No GP visit is recorded within 8 weeks of a positive FOBT result No GP visit is recorded within 6 months of a positive FOBT result No colonoscopy is recorded 4 months after a positive result No colonoscopy is recorded 6 months after a positive result

31 Duty of care Legal advice was obtained by DoHA Advice indicated that there was no additional duty of care imposed on medical professionals in regard to the National Program Practices will fulfill their duty of care by acting in accordance with existing professional standards and best practice More information:

32 Where patients can get an FOBT Free kit from National Bowel Cancer Screening Program for 50, 55, 60 and 65 year olds currently. With two yearly implementation by 2020 Purchase InSure kit from Cancer Council Victoria on or for $32.50 Purchase InSure kit from Enterix on or for $39.95 GPs; some local pathology services Some pharmacies see for participating suppliers Note - screening FOBTs are not Medicare rebatable unless doctor has given a pathology form and recommended the test be done

33 Key messages Regular screening using an FOBT can significantly reduce the number of Australians who die each year from bowel cancer It is estimated that the National Program has the potential to save lives per year General practice support of the program is integral to its success

34 For more information National Bowel Cancer Screening Program: (including multilingual information) Information Line FOBT Helpline Cancer Council Victoria: Helpline