1 / 48

Colonoscopy in crc screening

Colonoscopy in crc screening. NINA MARKOUTSAKI Gastroenterologist Specialised in Digestive Oncology Diplôme Inter Universitaire (DIU) de Cancérologie Digestive – Ile-de- France, Paris V, Université de Versailles. Colon cancer-Epidemiology.

trinaj
Download Presentation

Colonoscopy in crc screening

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Colonoscopy in crc screening NINA MARKOUTSAKI Gastroenterologist Specialised in Digestive Oncology Diplôme Inter Universitaire (DIU) de Cancérologie Digestive – Ile-de- France, Paris V, Université de Versailles

  2. Colon cancer-Epidemiology • Colorectal cancer (CRC) is a common and lethal cancer • CRC is infrequent before age 40 • CRC is the second most commonly diagnosed cancer in women and third most common in men • It has been estimated that more than 432,000 new CRC cases and 212,000 CRC deaths occur annually in Europe

  3. Colon cancer-Epidemiology • The incidence of CRC is slightly higher in men than in women • The prevalence of colorectal polyps in the general population is roughly 30 %.

  4. Crc-aetiopathogenesis • Most colorectal cancers (CRCs) arise from adenomas • Neoplastic changes result from both inherited and acquired genetic defects • Approximately 20% have a familial or congenital mutation(s) -earlier stage of life. • 80% are sporadic, with no obvious genetic causes-later in life Rao,Yamada Front Oncol 2013

  5. Crc types

  6. Sporadic crc • Development of sporadic cancer is a slow, age-influenced process with progressive acquisition of genetic mutations and/or epigenetic alterations under the influence of environmental and other external factors. Rao,Yamada Front Oncol 2013

  7. SUPPRESSOR OR CANONICAL PATHWAY-Fearon and Vogelstein model

  8. MSI (MUTATOR) PATHWAY

  9. Risk of crc • Increases with adenoma size, number, and histology • The polyp examined is representative of the individual’s propensity to form polyps and cancer • The number and types of lesions found will determine the appropriate interval for subsequent surveillance colonoscopy

  10. Rationale for screening • Most CRC are slow growing (doubling time of approx. 600 days) • Adenoma-Carcinoma Sequence >10 years • Removal of premalignant adenomas can prevent CRC and removal of localized cancer may prevent CRC-related death • Cancers discovered by screening tend to be less advanced and associated with greater probability of curative resection

  11. Adenoma-carcinoma sequence • Polypoid adenomas • Nonpolypoid adenomas (22-36% of adenomas) -Flat -Depressed • Hyperplastic polyps

  12. Screening for crc • Stool-based tests -Guaiac-based fecal occult blood test  -Fecal immunochemical test  -FIT-DNA 

  13. Screening for crc • Endoscopic and radiologic examinations -Colonoscopy -CTC (Virtual colonoscopy) -Flexible sigmoidoscopy +/- FIT or gFOBT

  14. GUIDELINE RECOMMENDATIONS • Guideline recommendations vary, depending on : - the prevalence of disease in a given population, - the availability of resources, - health care priorities, -aggressiveness with which preventive health care is promoted

  15. WORLDWIDE GUIDELINES • European Union • U.S. Preventive Services Task Force • U.S. Multi-Society Task Force on Colorectal Cancer Screening and Surveillance • American Cancer Society • American College of Physicians • Canadian Cancer Society, Canadian Association of Gastroenterology • British Society of Gastroenterology

  16. Screening-A suggested approach • Identifying a patient as average risk for CRC • Reviewing risks and benefits of screening options with the patients • Colonoscopy, for those, willing to undergo the procedure • Initial screening by FIT or CTC, for those, unable or unwilling to have a colonoscopy; - if positive FIT or CTC, then colonoscopy, within 3 months

  17. Colonoscopy

  18. Why Colonoscopy ? • Method of high sensitivity and specificity • Both detects and effectively removes pro-malignant and malignant lesions (Polyps, precursor of cancer) • Recommended by almost all international and national gastroenterology and cancer societies, as an initial screening modality

  19. Colonoscopy for average risk population • Colonoscopy represents the most important diagnostic and therapeutic modality for CRC prevention and treatment. • Recommended to be performed every 10 years for individuals of average risk starting from the age of 50 •  It is the final common pathway for all positive screening tests

  20. Screening Colonoscopy for high risk population • Patients whose first-degree relatives developed colorectal cancer before the age of 50 years -at 40 years or 10 years before cancer was diagnosed in the youngest affected family member, whichever is earlier • Hereditary non polyposis syndrome (HNPCC/Lynch syndrome) - at 20 to 25 years of age and every 1-3 years thereafter • Familial adenomatous Polyposis -at puberty and every 1-2 years thereafter

  21. Screening Colonoscopy for high risk population • Inflammatory Bowel Disease (IBD)-mainly UC -Initial colonoscopy, 7- 8 years after the diagnosis of pancolitis and 12 to 15 years after the diagnosis of left-sided colitis. Every 2 years thereafter.

  22. Evaluation of colonoscopy • Data from randomized controlled trials on the effects of screening colonoscopies on colorectal cancer (CRC) incidence and mortality, not available.  • Observational studies suggest that colonoscopy in the prior 10 years, reduced CRC incidence and mortality by over 60 % • Only 50% of eligible adults screened

  23. The National Polyp Study • 1418 patients • Colonoscopy-removal of one or more polyps • Mean follow-up of six years • Incidence of colon cancer : -88-90 % lower than in patients reported in other studies who had polyps that were not removed -76 % lower than in the general population. Winawer et al. N Engl J Med. 1993

  24. Efficacy in standard clinical practice of colonoscopic polypectomy in reducing colorectal cancer incidence • 1693 subjects of both sexes, aged 40-69 years • A total colon examination  • 1980-1987 • Removal of at least one adenoma larger than 5 mm in diameter • Mean follow up 10.5 years Citarda et al.Gut 2001

  25. Efficacy in standard clinical practice of colonoscopic polypectomy in reducing colorectal cancer incidence • Results: -Colonoscopic polypectomy substantially reduced the incidence of colorectal cancer in the cohort compared with that expected in the general population.(6 versus 17.7) Citarda et al.Gut 2001

  26. Reduced Risk of Colorectal Cancer Up to 10 Years After Screening, Surveillance, or Diagnostic Colonoscopy • Population-based case-control study • 3148 patients with a first diagnosis of CRC • 3274 subjects without CRC  • Detailed information on previous colonoscopy Brenner et al.Gastroenterology 2014

  27. Reduced Risk of Colorectal Cancer Up to 10 Years After Screening, Surveillance, or Diagnostic Colonoscopy • Results: • A previous colonoscopy was associated with a reduced subsequent risk of CRC, independently of the indication for the examination (1.7% vs 12.0%) • Colonoscopy was associated with a reduced risk of cancer in the right colon, regardless of the indication Brenner et al.Gastroenterology 2014

  28. Endoscopic Polypectomy

  29. Colonoscopy-barriers • Risks • Availability • Cost • Inadequate knowledge or awareness of CRC risk • Compliance

  30. Quality in colonoscopy • Vigorous bowel preparation • Cecal intubation rate (CIR) • Withdrawal time • Increased ADR • Complete resection rate • Complications • Patient satisfaction

  31. Adenoma detection rate (adr) • The proportion of screening colonoscopic examinations performed by a physician that detect one or more adenomas • The estimation of adenoma detection rates should be now considered as a current standard of care for endoscopists

  32. Adenoma Detection Rate and Risk of Colorectal Cancer and Death • Strong inverse association between the adenoma detection rate and the risk of interval cancer  • Every 1% increase in ADR, 3% decrease in the risk of interval CRC Corley et al. N Engl J Med 2014

  33. increased adr • Cecal intubation • Increased withdrawal time • Higher quality bowel prep • Antispasmodic use • Earlier procedure start • Greater colonoscopist experience

  34. Colonoscopy-limitations • Location of polyps: 2/3 of missed polyps, on proximal aspect of haustral folds • 12-24% of polyps in flexures and folds are missed • Nonpolypoid flat lesions may be missed. • Suboptimal bowel preparation • Endoscopists’ Training and Experience Pickhardt et al.Ann Intern Med 2004 Pab et al. Gastrointestinal Endosc 2005

  35. Blind areas difficult to observe

  36. Safety of screening colonoscopy • An invasive procedure • The complication rate not over 1 %, in large series -sedation related complications -colon perforation -post polypectomy bleeding - bowel preparation can lead to dehydration and electrolyte abnormalities

  37. New tech colonoscopy • High Definition Colonoscopy • Cap-assisted colonoscopy • Image enhanced colonoscopy (NBI, iScan , FICE) • FUSE colonoscopy • EndoRings/Endocuff colonoscopy • Third-Eye Retroscope

  38. Fuse-colonoscopy

  39. New tech colonoscopy • Majority of additionally detected adenomas are diminutive • Cost effectiveness • Better training to improve ADR with standard forward viewing colonoscopy

  40. Take home messages • Colorectal cancer (CRC) is a common and lethal cancer • CRC is infrequent before age 40 • Most colorectal cancers (CRCs) arise from adenomas • Before deciding how best to screen and when to initiate screening, clinicians should determine the individual patient's level of risk.

  41. Take home messages • Colonoscopy recommended by almost all international and national gastroenterology and cancer societies, as an initial screening modality • Removal of premalignant adenomas can prevent CRC and removal of localized cancer may prevent CRC-related death • Colonoscopy is the final common pathway for all positive screening tests

  42. Take home messages • Support for the role of colonoscopy in CRC prevention derives entirely from indirect evidence and observational studies • Colonoscopy reduces CRC incidence and mortality by over 60 % • Need to optimize the quality and effectiveness of colonoscopy

  43. Take home messages • The estimated adenoma detection rates should be now considered as a current standard of care for endoscopists • Limitations to successful screening colonoscopy: the blind location of polyps, nonpolypoid flat lesions, poor bowel preparation and lack of endoscopists’ experience • New frontiers in screening colonoscopy will focus on improving colonoscopy techniques

  44. Get the test. Get the polyp. Get the cure.

  45. Thank you

More Related