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

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

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

Colorectal Cancer Awareness March is colon cancer awareness month! Common Lethal Preventable Third most common cancer Second leading cause of cancer related death

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

Incidence Worldwide Worldwide: 500,000 lives will be lost

50 yrs of age is the Golden Age for Colorectal Cancer prevention 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

Incidence Age is a major risk factor Lifetime risk is about 5-6% 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

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

Probable Risk Factors Dietary – Environmental - Lifestyle -Diets high in fat & cholesterol -Diets low in fiber Alcohol consumption Cigarette smoking Sedentary lifestyle/physical inactivity Obesity -Specifically red meat (greater than 1 pound/week)

Questionable Risk Factors Diabetes mellitus Pelvic radiation Breast cancer

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

“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 -fever of unknown origin -unintentional weight loss -fatigue -abdominal tenderness -abdominal distention -ascites

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

Colorectal Polyps

Colorectal Polyps -Precursors for Screening- Polyps are the precursor for determining how often we screen a patient for colorectal cancer: it is also based on the (1) size (2) amount/number (3) histology Histology: Characteristic features under the microscope (Biopsy report proves)

Colon Cancer Where 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 -The vast majority of colorectal cancers are adenocarcinomas, which arise from pre-existing adenomatous polyps that develop in the normal colonic mucosa -Dysplasia: abnormal growth or development of cells, tissue, bone, or an organ

Histological Transition from normal colon mucosa to adenomatous polyps to dysplasia which subsequently results into colorectal cancer

Progression of Colorectal Cancer

-Right-sided colon cancers: larger and more likely to bleed -Left-sided colon cancers: smaller and more likely to obstruct

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

FOBTs Fecal occult blood test Simple 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 Detect hidden blood

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

Sigmoidoscopy Effectiveness Risks and Disadvantages 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

Flexible Sigmoidoscope

Provides a x-ray picture of the rectum and entire colon 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 Utilized in patients that are high risk for a procedure Those that could not tolerate a sedation/procedure

Barium Enema Effectiveness Risks and disadvantages: 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

Colonoscopy

Colonoscopy

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

Colonoscopy Effectiveness Risks and Disadvantages 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

Endoscopy

Polypectomy

Hidden Disease Processes of the Colon

Diverticulosis 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

Diverticular Bleed Can be a cause for anemia of unknown origin

IBD: Ulcerative Colitis

IBD: Ulcerative Colitis

Clostridium Difficile Colitis These are pseudomembranes *Antibiotics – is the major cause of C. diff (iatrogenic) *Major antibiotic: Clindamycin – which causes C. diff *Flagyl  antibiotics (treatment for C. diff) *Vancomycin (PO) is the second choice (expensive, and you don’t want to develop vancomycin resistant strains)

Pedunculated Polyp with Cancer Friable Non-mobile This patient most likely had rectal bleeding or at least occult + stool

Colorectal Carcinoma

Surgical Intervention

Wireless Capsule Endoscopy "The Camera in a Pill" Capsule Endoscopy is a term used to describe a miniature capsule used to record images through the digestive tract for use in medical purposes It is an imaging device for the detection of gastrointestinal diseases and has been hailed as a major breakthrough in medical technology. Many improvements in the product are enabling the Camera Capsule to see areas not possible with current endoscopic equipment.

Emerging Tests Virtual colonoscopy Fecal genetics 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

Virtual Colonoscopy Procedure Effectiveness 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

Virtual Colonoscopy

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

Fecal Genetics Procedure Effectiveness Risks and Disadvantages 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

Screening Average Risk Increased Risk Begin at age 50 American College of Gastroenterology recommends colonoscopy Discuss with your doctor a screening plan that is best for you Increased Risk Begin screening at age 40 or 10 years younger than the earliest diagnosis in your family, whichever comes first

Screening Personal history of IBD Depends on severity and duration of the disease Screening begins about 8 years after diagnosis of the disease if entire colon is involved (pan-colonic) Screening begins 15 years after diagnosis of disease if limited to left colon Repeated every one to two years thereafter

Colorectal cancer is about 90% curable if caught in the early stages Benefits of Screening Colorectal cancer is about 90% curable if caught in the early stages  

Summary http://www.chgastro.com/about.html Colorectal cancer is highly lethal, fortunately it is greatly preventable! Proper Diet and Lifestyle modifications are important for the health of your colon Colorectal cancer is the 3rd most common cancer risk and 2nd deadliest cancer for both men & women Colorectal cancer screening for average-risk patients begins at age 50! Colonoscopy remains the gold standard for colorectal cancer screening

Happy St. Patrick’s Day! Now you can make a Difference Educate your family and friends about the importance of Colorectal Cancer Screening!