Colorectal Cancer The Race to Cancer Prevention

1. Colorectal CancerThe Race to Cancer Prevention Meredith L. Cashdollar PA-C Chambersburg Gastroenterology Assoc., LTD

2. Colorectal Anatomy • The term “colorectal” refers to the lower gastrointestinal tract, which is divided into: 1. cecum 2. ascending (right colon) 3. transverse colon 4. descending (left colon) 5. sigmoid colon 6. rectum • Large Intestine (Colon) is approximately 5 to 6 feet in length and one to two inches in width • Primary role: salt & water absorption

3. Colorectal Anatomy • The rectum is located within the pelvis and is not a true intra-abdominal structure • The diameter of the rectum is larger than that of the colon • Primary purpose of the rectum: storage reservoir for stool

4. Colorectal Cancer AwarenessMarch is colon cancer awareness month! • Colorectal Cancer • Common • Lethal • Preventable • Third most common cancer • Second leading cause of cancer related death

5. Epidemiology • United States • (+)145,000 new cases each year -105,000 = colon cancer -40,000 = rectal cancer • 56,000 Americans will die of CRC/year

6. Incidence Worldwide • Worldwide: 500,000 lives will be lost

7. How many of you have parents, grandparents and relatives over the age of 50? 50 yrs of age is the Golden Age for Colorectal Cancer prevention

8. Incidence • Age is a major risk factor • CRC increases after the age of 50 • 90% of cases occur after the age of 50 • Rare to occur before age 40 (not unheard of) • Lifetime risk is about 5-6% • American Cancer Society recommends screening starting at age 50 for average-risk adults

9. Known Risk Factors • Personal history of adenomatous polyps • Personal/Family History of IBD • Crohn’s Disease & Ulcerative Colitis • Increasing Age • Genetic Predisposition • Family history of CRC/Adenomatous polyps • Familial Adenomatous Polyposis (FAP) • 100% chance of CRC by 30yrs. • Hereditary Nonpolyposis Colorectal Cancer

10. Probable Risk Factors • Dietary – Environmental - Lifestyle -Diets high in fat & cholesterol -Diets low in fiber • Alcohol consumption • Cigarette smoking • Sedentary lifestyle/physical inactivity • Obesity

11. Questionable Risk Factors • Diabetes mellitus • Pelvic radiation • Breast cancer

12. Protective Factors • Diet rich in fiber: fruits, vegetables, grains • Regular physical activity • Maintaining a healthy body weight • Regular use of aspirin • Diet high in calcium • Vitamin B6 • Folic acid • Omega-3 fatty acids

13. “Red Flag” Signs/Symptoms • 50% of patients present with abdominal pain • 35% present with altered bowels • 30% present with occult-bleeding • 15% present with intestinal obstruction

14. Colorectal Polyps • A colorectal polyp is a growth that sticks out of the lining of the colon or rectum • Polyps of the colon and rectum are usually benign and produce no symptoms, but they may cause painless rectal bleeding • There may be single or multiple polyps and they become more common as people age. • Over time, certain types of polyps, called adenomatous polyps, may develop into cancer • Another common type of polyp found in the colon is called a hyperplastic polyp, which is generally not at risk for developing into colon cancer

15. Colorectal Polyps

16. Colorectal Polyps-Precursors for Screening-

17. Colon CancerWhere Does It Begin? Adenoma-carcinoma Sequence Most colorectal cancers arise from polyps: • Adenomatous polyps • Adenomas progress  Dysplasia • Dysplasia progress  Cancer • Majority of colorectal cancers are adenocarcinomas *Takes approximately 7-10 years to occur

19. Progression of Colorectal Cancer

21. Screening • Two opportunities to prevent cancer and cancer related death • Finding and removing polyps • Removing early cancers to improve prognosis • Available tests • FOBTs (Fecal Occult Blood Test) • Flexible sigmoidoscopy • Double contrast barium enema • Colonoscopy • Virtual Colonoscopy

22. FOBTs • Fecal occult blood test • Colorectal cancers/polyps often bleed • FOBT detect microscopic amounts of blood in the stool • Simple test • Chemically coated cards • Place small amount of stool (2 samples) from 3 consecutive stools • Reduces the risk of cancer related death by up to one-third

23. Sigmoidoscopy • Allows direct visualization of the lining of the lower half of the colon • Area were half of all cancers occur • Approximately the first 60cm of the colon • Procedure • Thin maneuverable tube with a light and camera is advanced along the rectum and left-sided colon

24. Sigmoidoscopy • Effectiveness • Reduces cancer related death by 66% when done every 5 years • Risks and Disadvantages • Perforation occurs in about 2 per every 10,000 procedures • Does not exam the entire colon • Right-sided cancers/polyps can be missed

25. Flexible Sigmoidoscope

26. Barium Enema Provides a x-ray picture of the rectum and entire colon • Procedure: Liquid barium coats the entire inside of the colon • Reveals structural abnormalities such as polyps and cancers • Preparation is a laxative • Does not require sedation

27. Barium Enema • Effectiveness • Detects about half of large polyps & 40% of all polyps in the colon/rectum • Risks and disadvantages: • Relatively safe • Helps to reduce the risk of cancer related deaths but not definitively proven • If an abnormality is found, further testing is required

28. Colonoscopy

29. Colonoscopy

30. Colonoscopy • Allows direct visualization of the lining of the rectum and entire colon • Procedure • Thin maneuverable tube with a light and camera is guided throughout the entire colon • Preparation is laxative • Requires sedation in most instances

31. Colonoscopy • Effectiveness • Detects most small polyps and almost all large polyps and cancers • Polyps and some cancers can be removed at the time of the procedure • Risks and Disadvantages • Bleeding or perforation could occur in about 1 in 1,000 people • Requires sedation • Diagnostic & Therapeutic

32. Endoscopy

33. Polypectomy

34. Hidden Disease Processes of the Colon

35. Diverticulosis: Saclike herniations of the mucosal layer of the colon through the muscular wall Common among older persons (50%/50yr.) Usually producing no symptoms except occasional rectal bleeding Diverticulosis

36. Diverticulosis

37. Diverticular Bleed

38. IBD: Ulcerative Colitis

39. IBD: Ulcerative Colitis

40. Clostridium Difficile Colitis

41. Pedunculated Polyp with Cancer

42. Colorectal Carcinoma

44. Surgical Intervention

45. Wireless Capsule Endoscopy"The Camera in a Pill"

46. Emerging Tests • Virtual colonoscopy • CT scan of the bowel allows for visualization of the entire colon lining • Fecal genetics • PreGen-Plus • Detects presence of abnormalities associated with pathogenesis of colorectal cancer • DNA from colorectal cancers is shed in the stool and can be isolated

47. Virtual Colonoscopy • Procedure • CT scan is completed after air insufflation of the colon • Preparation is a laxative • Sedation is not required • Effectiveness • Conflicting results in studies to date

48. Virtual Colonoscopy

49. Virtual Colonoscopy • Risks and Disadvantages • Relatively safe • Uncomfortable • Lack of widespread availability • If abnormality is found, conventional colonoscopy is recommended • Size of polyp that should lead to optical colonoscopy has not been agreed upon

50. Fecal Genetics • Procedure • Complete bowel movement must be collected and shipped in ice to specialized lab • Effectiveness • More effective than FOBTs for advanced cancers in one study to date • Risks and Disadvantages • Not widely available • Complex and expensive