Screening and early detection of GI cancers.pptx

gi cancer screening

1. Screening and early detection of GI cancers Parag Dashatwar Consultant Gastroenterologist

2. GI Cancer in India Incidence of cancer Mortality Average years of life lost Cardiac causes - 11 years Cancer - 15 years

3. Frustrating quest to cure cancer Curative treatment “….we concluded that some 35 years of intense effort focused largely on improving treatment must be judged a qualified failure. Now, with 12 more years of data and experience, we see little reason to change that conclusion…..” NE JM,1997;336:1569-74 In 1986

4. Preventive medicine model refers to measures taken to prevent illness or injury, rather than curing them Primary prevention – avoids the development of a disease Secondary prevention – activities are aimed at early disease detection, thereby increasing opportunities for interventions to prevent progression of the disease or emergence of symptoms Tertiary prevention – reduces the negative impact of an already established disease by restoring function and reducing disease-related complications.

5. Rationale for screening and early detection

6. Screening vs early detection

7. Principles of screening Disease should be important health problem in terms of frequency and/or severity. Natural history of disease presents window of opportunity for early detection. Effective treatment should be available that favorably alters natural history of disease. Treatment should be more effective if initiated earlier than during the symptomatic stage. Suitable screening test should be available . Appropriate screening strategy for the target population (i.e. age to begin and screening interval)

8. Ideal screening test cheap Sensitive Specific Accessible Safe Acceptable

9. Pitfalls of screening Biases in screening Lead time bias: Early detection does not change outcome Length-bias sampling : Slow growing tumor are detected but fast growing tumors missed Referral/volunteer bias: People who volunteer to participate are more health conscious and compliant to advice – better prognosis. False-positive test result: Lead to anxiety and unnecessary invasive diagnostic procedures. Over diagnosis: Diagnosis of a condition that would not have become clinically significant had it not been detected by screening. False-negative test result: Falsely reassure an individual with subsequent clinical signs or symptoms of cancer and thereby actually delay diagnosis and effective treatment.

10. Types of screening Organized screening Mass screening – average risk population S elective or targeted screening – high risk population Opportunistic screening – going to screening on own initiative or doctor’s recommendation during medical visit for various reason

11. Esophageal cancer F ourth common cause of cancer-related deaths in India Two major types: Esophageal squamous cell carcinoma (ESCC) accounts for up to 80% Esophageal adenocarcinoma (EAC) is on the increase due to changing lifestyles Esophageal cancer presents late and therefore has a poor prognosis

12. Risk factors for EAC Gastroesophageal reflux (GERD) Male sex Age 50 years or older White race Hiatal hernia Obesity Tobacco smoking Family h/o BE or EAC in 1 St degree relative Caustic injury to esophagus Long standing achalasia cardia

13. Risk factors for ESCC The etiological factors for SCC tobacco consumption in various forms, Alcohol hot beverages poor nutrition h/o H&N cancers cervical webs Familial syndromes

14. Precursor lesions Barrett’s esophagus (BE) – Chronic inflammation due to GERD or other irritants leads to intestinal metaplasia. Continued irritation will lead to low-grade dysplasia, which will progress to high-grade dysplasia and then to adenocarcinoma. Barrett’s esophagus – (HGD – 6% and 19% per year, non dysplastic – 1%/pt yr )

15. Screening techniques for ESCC and EAC Upper GI endoscopy – gold standard, WLE, IEE, chromoendoscopy, TNE Breath testing – detect volatile organic compounds in exhaled air, sensitivity of 91% and specificity of 74% Cytosponge – ingestible capsule containing a sponge attached to a string. sensitivity of 73% and a specificity of 94% for lesion > 1cm

16. Effectiveness of screening meta-analysis also demonstrated a survival advantage for EAC detected from screening protocols compared to symptom-based EAC diagnosis (relative risk of mortality, 0.73; 95% CI, 0.57–0.94), associated with earlier-stage EAC diagnosis

17. Screening for esophageal carcinoma No Indian guidelines or data on systematic screening In the West No recommendation on ESCC screening find EAC in average risk population is not recommended because of low prevalence Screening is recommended in patients with GERD symptoms despite adequate treatment especially in those with GERD and dysphagia, bleeding, anemia, weight loss, or recurrent vomiting. No further surveillance is recommended if endoscopy shows negative results for BE. In patients with BE and no dysplasia, surveillance examinations should occur at intervals of 3 to 5 years; shorter intervals are indicated in BE

18. Screening for esophageal carcinoma In China In areas with low income levels and limited health care access - 1 screening endoscopy at age 50 years, with 5-year follow-up for low-grade dysplasia and 3-year follow-up for high-grade dysplasia. In areas with higher incomes and better health care access - 3 screening endoscopies at 5-year intervals starting at the age of 40 years, with the equivalent monitoring of low-grade and high-grade dysplasia.

19. Gastric cancer In India, the incidence rate of gastric is very low compared to that in western and far eastern countries Approximately 50,000 new gastric cancer cases will be reported annually in India. National survey of cancer mortality in India – gastric carcinoma was the second most common cause of cancer-related deaths amongst men and women Regional variation – South India, Mizoram

20. Risk factors for gastric cancer Non modifiable Male sex Age Ethnicity Family history Modifiable Obesity Smoking tobacco High salt diet Low fresh fruits and vegetable intake H pylori infection

21. Precursor lesions – The Correa Cascade Chronic gastritis seems to lead to atrophic gastritis, which leads to intestinal metaplasia, which can develop into dysplasia and, ultimately, cancer

22. Within 5 years of diagnosis, the annual incidence of gastric cancer 0.1% for patients with atrophic gastritis 0.25% for intestinal metaplasia 0.6% for mild-to-moderate dysplasia 6% for severe dysplasia. The progression depends on the histologic subtype of intestinal metaplasia Risk of progression: incomplete metaplasia > complete metaplasia

23. Screening Techniques for Gastric Cancer Upper GI endoscopy – Gold standard Gastric imaging – sensitivity 40-60%, part of mass screening programmes in Korea and Japan Other modalities Serum pepsinogen Serum trefoil factor 3 (TFF3) MicroRNA Multianalyte blood tests

24. Effectiveness of gastric cancer screening Observational studies in areas of high gastric cancer incidence: early stages and an overall decline in gastric cancer mortality no data from large randomized trials demonstrating lower gastric cancer-related mortality in screened populations Risk of bias Screening for gastric cancer may be cost-effective for high-risk subgroups, but not low-risk populations

25. Screening strategy Universal or population-based screening – countries with a high incidence of gastric cancer ( eg , Japan, Korea, Venezuela, and Chile) In Japan: individuals older than 50 years with conventional double-contrast barium radiograph every year or upper endoscopy every two to three years. In Korea: upper endoscopy is recommended every two years for individuals aged 40 to 75 years

26. In areas of low gastric cancer incidence – screening with upper endoscopy should be reserved for specific high-risk subgroups Effect of H. pylori eradication – uncertain Individuals at increased risk for gastric cancer include those with the following: Gastric adenomas Pernicious anemia Gastric intestinal metaplasia Familial adenomatous polyposis Lynch syndrome Peutz-Jeghers syndrome Juvenile polyposis syndrome

27. Colorectal cancers In India, the annual incidence rates (AARs) for colon cancer men - 4.4 per 100000 women - 3.9 per 100000 Colon cancer ranks 8th and rectal cancer ranks 9th among men. For women, rectal cancer does not figure in the top 10 cancers, whereas colon cancer ranks 9th. In the 2013 report, the highest AAR in men for CRCs was recorded in Thiruvananthapuram (4.1) followed by Bangalore (3.9) and Mumbai (3.7) . The highest AAR in women for CRCs was recorded in Nagaland (5.2) followed by Aizwal (4.5)

28. Globally, colorectal cancer (CRC) is one of the leading cause of mortality and morbidity from cancer. Several developed Asians countries have surpassed the United States and other Western European countries in burden of CRC. Although the incidence of CRC in India has increased only marginally, it is now the fifth most common cause of cancer mortality among Indian men and women

29. Risk factors of CRC Advancing age Inflammatory bowel disease family h/o CRC or polyps. Genetic syndromes such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colorectal cancer (Lynch syndrome) Lack of regular physical activity A diet low in fruit and vegetables A low-fiber and high-fat diet, or a diet high in processed meats Overweight and obesity Alcohol consumption Tobacco use

30. Precursor lesion – Adenoma carcinoma sequence Most CRC arise from adenomatous colon polyps that progress from small (<8 mm) to large (≥8 mm) polyps, then to dysplasia and carcinoma. Adenomatous polyps occur in about 30 percent of men and about 20 percent of women. Progression from adenoma to carcinoma is believed to take an average of approximately 10 years

31. Screening techniques for CRC Colonoscopy Fecal immunochemical testing (FIT) Multitarget stool DNA testing CT colonography Simgoidoscopy combined with FIT Sigmoidoscopy Guaiac-based fecal occult blood test Capsule colonoscopy

32. Effectiveness of CRC screening biennial FIT, gFOBT , single/5-yearly FS, and 10-yearly colonoscopy screenings reduced CRC-specific mortality significantly, and 10-yearly colonoscopy is the most effective with a mortality reduction of 73%. The effectiveness of screening increases at younger screening initiation ages and higher adherences. Cancers (Basel). 2023 Apr; 15(7): 1948.

33. Screening strategy For average risk individual Age 50-75 – Grade A Age45-49 – grade B Age > 85 – not recommeded Stool-based screening tests and intervals are as follows: Guaiac-based fecal occult blood test (FOBT), every year Fecal immunochemical test (FIT), every year FIT-DNA, every 1 or 3 years Direct visualization screening tests and intervals are as follows: Colonoscopy, every 10 years Computed tomographic (CT) colonography, every 5 years Flexible sigmoidoscopy, every 5 years Flexible sigmoidoscopy with FIT; sigmoidoscopy every 10 years, with FIT every year

34. Take home points Overall incidence of cancer in India rising because of epidemiological transition, aging population and changing lifestyles GI cancers are among leading causes of cancer related mortality in India Increased mortality is likely attributable to late stage presentation GI cancer for the most part evolve slowly from clearly defined precursor lesions, hence are the ideal candidates for screening At present targeted and opportunistic screening can help identify precursor lesions and early stage cancer