Colon Polyps and Cancer Flashcards Preview

X Clin Med III Exam 2 > Colon Polyps and Cancer > Flashcards

Flashcards in Colon Polyps and Cancer Deck (47)
Loading flashcards...
1

What is a polyp?

Growth on inner surface of colon

2

How a polyp might look on endoscopy

Pedunculated (attached by stem/stalk)
Sessile (flat)
*they influence the screening tests

3

Histologic classifications of polyps

Hyperplastic (non-neoplastic and benign)
Pseudopolyps (nonneoplastic-IBD/UC)
Adenomas (neoplastic and pre-cancerous)
Sessile serrated polyps (pre-cancerous)

4

Types of adenomatous polyps

Tubular adenoma (most common)
Tubulovillous adenoma
Villous adenoma

5

Tell me about colon adenomas

2/3 of all polyps
Common in adults>50
Usually asymptomatic (large may bleed)
More than half of colorectal cancers arise from these (progression about 10 yrs so early detection and removal)

6

When is a polyp a high risk adenoma?

"Advanced"
>1 cm, villous component, high grade dysplasia

7

When does the risk of colorectal cancer increase with adenomatous polyps?

The number, size and histology (influence surveillance intervals)

8

Sites of colorectal cancer

Left sided is most common presentation
Right sided rates are rising tho

9

Non-modifiable risk factors of colorectal cancer

Personal or family hx (adenomas or colon cancer, FAP or HNPCC-hereditary sxs)
Age >50
IBD>8-10 yrs
African American

10

Modifiable risk factors of colorectal cancer

Tobacco use
Excess alcohol consumption
Diet (high fat and low fiber or more red meat)
Obesity
Diabetes

11

Red flags in the presentation of colorectal cancer

Change in BH
Hematochezia or occult blood in stool
Iron deficiency anemia
Anorexia/weight loss
Abd pain

12

Presentation of colorectal cancer

Often asymptomatic
Cachetic, pallor, LAD
Abd distension, ascites, mass, organomegaly
DRE-hemoccult positive or rectal mass

13

Diagnostics for colorectal cancer

CBC-for IDA
Liver tests (alk phos with liver mets)
Carcinoembryonic antigen
Colonoscopy
Chest/abd/pelvic CT to look for tumor

14

What is carcinoembryonic antigen used for?

Prognostic indicator and monitor for recurrence of colorectal cancer

15

Colon cancer on imaging

Classic apple core lesion

16

How to stage colon cancer

Depth of tumor invasion
Status of regional nodes
Presence of absence of mets

17

Surveillance needed for colorectal cancer

Serial CEA levels
Annual surveillance with CT chest/abd/pelvis
Periodic colonoscopy

18

Screening vs surveillance

Screening is early detection looking for early stage of precancerous lesions in asymptomatic ppl with no history
Surveillance (follow up testing in pts with polyps, CA or IBD)

19

Types of preventative tests for colon cancer

*detect colon polyps and CRC
Colonoscopy, flex sig, CT colonography, double contrast barium enema no longer used!

20

Stool tests for colon cancer

*detect but don't precent cancer
gFOBT
FIT (fecal immunochemical test)
FIT-DNA (cologuard)

21

Colonoscopy for colon cancer

Gold standard (diagnostic and therapeutic)
-See whole colon, remove polyps and take biopsies
-Detect precancerous lesions and CRC

22

Downside to colonoscopy

Invasive
Risk of major complications like perf or bleeding
Operator dependence

23

Colonoscopy following a polypectomy

Surveillance depends on number, size and histoloy
Check with the endoscopist

24

Flex sig for colon cancer

Lower benefit in protection against right sided colon CA
If find polyps, probably need colonoscopy to r/o proximal lesions
-Limited prep, no sedation, lower cost and lower risk of perf

25

Downside to CT colonograpy for colon cancer

Can miss flat or small polyps (virtual)
There is also radiation exposure (no sedation but need bowel prep)

26

What must be done with a positive CT colonography

Colonoscopy

27

What is gFOBT?

Fecal occult blood test- stool guaiac (indicates hgb by a peroxidase rxn)
-Hemoccult SENSA is a take home test and recommended
2 specimens on 3 consecutive stools
False positives

28

Diet before gFOBT

Avoid red meats, iron supplements, Vit C and NSAIDs

29

Preferred colon cancer detection test

FIT

30

FIT colon cancer test

Non invasive
Tests for presence of human hb and less false positives than FOBT
Single specimen of spontaneous stool
No diet restrictions