Colon Cancer Flashcards
Which two polyp types are not precancerous?
- Hyperplastic
2. Pseudopolyps (IBD)
Which two polyp types are precancerous?
- Adenomas*
- Tubular adenoma*** (MC)
- Tubulovillous adenoma
- Villous adenoma - Sessile serrated polyps
What 3 characteristics of polyps influence surveillance interval recommendations
- #
- Size
- Histology (degree of dysplastic change)
Most common type of colon cancer?
adenocarcinoma
- MC on left side (sigmoid, rectum)
- Right-sided are increasing in prevalence
Colorectal cancer risk factors
- Age >50
- IBD (>8-10 years)
- African American
- Family history (familial Adenomatous Polyposis, Hereditary nonpolyposis colon cancer)
- Smoking
- Alcohol
- DM type 2
- Obesity
- Red meat
What test may be elevated if colorectal cancer spreads to the liver?
Alk phos
What lab is a good prognostic indicator and is used to monitor for recurrence?
Carcinoembryonic antigen (CEA)
Hemoccult SENSA test
- take home
- 2 specimens on 3 consecutive stools
- Avoid red meat, iron supplements, Vitamin C and NSAIDS before test
FIT (CRC screening test)
Preferred CRC detection test**
- tests for human hemoglobin
- Fewer false positives
- 1 specimen
FIT DNA (Cologuard)
- $$$$
- Higher false positive rate than the FIT
- Excellent negative predictive value
When should normal healthy folks begin screening for colorectal cancer?
age 50
45 if African American
When should you start screening for colorectal cancer in increase risk individuals?
Family history:
- one first degree relative with CRC, or advanced adenoma before age 60
- two 2nd degree relatives
- *Start at 40 or 10 years prior to age of diagnosis
- ->Colonoscopy every 5 years
When do you stop screening for colorectal cancer?
age 75 (if they are up to date with screening)
or
life expectancy <10 years
If a patient has never been screened for colorectal cancer, up to what age can you consider to screen?
85
How often should the FIT test be done?
annually
Familial Adenomatous Polyposis (FAP)
- Autosomal dominant
- Increased risk of other cancers: duodenal and gastronomas**, thyroid (so–>also need endoscopy)
Screening: start annual colonoscopy 10-12 through age 40 if negative
Tx: prophylactic colectomy **
Hereditary NonPolyposis Colon Cancer
- “Lynch Syndrome”
- Autosomal Dominant
- right sided colon CA**
- Increased risk of endometrial cancer**
-Amsterdam Criteria for diagnosis: "3-2-1" 3 affected members 2 generations 1 under age 50
Screening:
-colonoscopy starting at age 20-25 (or 2-5 years prior to earliest age of onset in affected family member)
- Pelvic exam with endometrial bx with transvaginal US
- EGD at age 30-35 every 2-3 years
