Colorectal cancer Flashcards
most colorectal cancers are in what part of colon?
rectosigmoid
most common type colon cancer (think cellular level) and most common cause
> Most are adenocarcinomas
>Polyps form first and can transform into CRCs
How does colorectal cancer spread?
- Directly into tissue
- Through lymph
- Through blood
- Seeding: small piece of tumor breaks off and starts to grow somewhere else?
Complications from colorectal cancer
- Bowel obstruction
- Bowel perforation
- Abscess formation
- Fistula formation - especially if there is an obstruction
- Bleeding
Risk factors for CRC
- Age (>45)
- Genetics
- Crohn’s disease
- Familial adenomatous polyposis
- Ulcerative colitis
- John Cunningham virus
- HPV
- Smoking
- Obesity
- Physical inactivity
- Heavy alcohol consumption
- High fat diet especially with lower fiber
when do we start screening- average vs high risk
- 45 years of age screening = average risk
* Before 45 screening starts = high risk
types of screening tests for CRC
- FOBT (fecal occult blood test)* = testing stool for blood you cannot see, indicates bleeding, need to follow up with colonscopy
- if test negative does not mean you do NOT have cancer, just means no blood
- Fecal Immunochemical Test (FIT)
- FIT DNA Test
- Colonoscopy* - looking for precancerous polyps
- Double contrast barium enema
> > > > conversation with provider about right test
what does a negative FOBT mean?
= testing stool for blood you cannot see, indicates bleeding, need to follow up with colonscopy
*if test negative does not mean you do NOT have cancer, just means no blood
assessment for CRC (general vs 3 main)
- History: risk
- Changes in bowel habits
- Changes in stool
- Fatigue
- Pain
- Abdominal fullness
- Weight loss
- Distension
- Masses
3 MAIN:
- Rectal bleeding
- Anemia
- Changes in stool
Bleeding in CRC
- May be trace amounts
- Mahogany (bleeding further up) vs Bright red (bleeding lower down)
- Gross blood most common with tumors on left side of colon/rectum
• Gross blood most common with tumors on _______ side of colon/rectum
left
CRC and blockage: feels like , most common in
- Most common in transverse and descending colon
* Feels like: Gas pains, Cramping, Incomplete evacuation
partial vs complete bowel obstruction
• Partial bowel obstruction -->Visible peristaltic waves --> Tinkling bowel sounds • Complete bowel obstruction --> Absence of bowel sounds
Rectosigmoid Cancers characterized by
- Hematochezia
- Straining
- Narrowing of stools
Right Sided Tumors characterized by (3)
- Mahogany colored stools
- Anemia
- Palpable mass
diagnostics for CRC
- H&H
- Liver enzymes
- FOBT
- Carcinoembryonic antigen
- Double Contrast barium enema
- CT
- MRI
- CT-Guided virtual colonoscopy
- Sigmoidoscopy –> just take a look at lower portion of colon
- Colonoscopy –> look @ entire colon
colonoscopy vs sigmoidoscopy
- Sigmoidoscopy –> just take a look at lower portion of colon
- Colonoscopy –> look @ entire colon
Grossest thing I have ever seen since I have started working in healthcare
a ton of corn stuck in this dudes colon during his colonoscopy. It was like a disgusting treasure hunt
“What are these little easter eggs?”
said @sepik - ruining corn and easter egg hunts for the rest of my life
Interventions for CRC
- Surgery: Colon resection
- Radiation therapy
- Chemotherapy
- Comfort
Goal of surgery and approach for CRC
• Goal: Remove diseased tissue • Surgery approach depends on -Size of tumor -Condition of colon -Condition of patient -Location of tumor -Extent of disease -Color resection
When piece of colon is diverted through opening in abd wall in order to bypass part of colon
colostomy
entire colon is removed, ileum makes stoma
ileostomy
◦ Colostomy w/ mucous fistula
= 2 different stomas
‣ mucous fistula= bottom = drains mucous
‣ top fistula= drains stool
2 part surgery:
- ->remove colon and have ileostomy, form j pouch that has time to heal
- ->then reattach ileum to j pouch at anus , more control over BM
◦ Ileoanal pull through
