Colon polys and Cancer Flashcards
Proximal colon
ascending and transverse colon
What are the 4 parts of the colon
- ascending
- transverse
- descending
- sigmoid
What vitamin does the colon absorb
vitamin K
What is a polyp
growth in the inner lining of the colon
How are polyps diagnosed
- colonoscopy
- barium enema
- sigmoidoscopy
Physical exams signs common with polyps
usually asymptomatic
can have GI bleed or intestinal obstruction
Symptoms of polyps
- BRBPR
- rectal tenesmus
- change in bowel habits
What are the 4 morphologic characteristic of polyps
- sessile
- flat
- pedunculated (polypoid)
- depressed
Which two shapes of polyps are associated with malignancy
flat and depressed
Classifications of non- neoplastic polyps
- mucosal
- inflammatory pseudopolyps
- hyperplastic
- submucosal
- hamartamous
Classification of neoplastic polyps
adenomatous polyps
What are muscoal polyps
small polyps that resemble adjacent tissue and are histologically normal
What are inflammatory pseudopolyps?
irregularly shaped islands of intact mucosal
What causes inflammatory pseudopolyps
mucosal ulceration and regeneration (inflammatory bowel disease process)
What are the most common non-neoplastic polyps
hyperplastic
What pattern do hyperplastic polyps present with
serrated or sawtooth pattern
Where are most hyperplastic polys found?
rectosigmoid
What are the types of submucosal polyps
- lymphoid
- fibromas
- lipoma (most common)
Why do hyperplastic polyps have to be removed
they are impossible to distinguish from adenomatous polys so they need to be biopsied
Which type of polyps do most polyposis syndromes derive from
hamartamous polyps
How long does it take adenomatous polyps to develop into cancer? What type of cancer?
7-10 years
adenocarcinoma
What are some risk factors for adenomatous polyps
- older age
- increased BMI
- lack of physical activity
- smoking
- men>women
What are the histological classifications of adenomatous polpys
- tubular
- tubulovillous
- villous
Which type of adenomatous polyp has the highest malignancy potential
villous
Which type of adenomatous polyp is most common
tubular
What characteristics of adenomatous polyps are associated with high CRC risk
- villous histology
- high grade dysplasia
- number and size (one or more greater than 1 cm or more than 3 of any size)
Screening/diagnostic tests for polyps
- FOBT
- double contrast barium enema
- CT colonography
- flex sig
- colonoscopy
What does an FOBT look for
blood in the stool–> bleeding polyp
What would a double contrast enema show if there were polyps
applecore narrowing of the colon with distension
What is the gold standard for examining polyps? What major benefit does it have?
colonoscopy
can remove the polyps immediately
What are the risk associated with colonoscopy
- perforation
- bleeding
- intolerance to sedation
- dehydration/electrolyte imbalance in elderly
What is a polypectomy
removal of polpys
What technique is used to remove a <5mm diminutive polyp
cold biopsy forceps or cold snare excision
What technique is used to remove a 5-10 cm polyp
standard snare excision
What technique is used to remove large sessile polyps (2-3cm)
piecemeal excision
or
saline assisted endoscopic mucosal resection
When should you do a follow up colonoscopy if you removed a polyp >2cm or you are concerned for incomplete removal of polyps
3-6 months
If you find >10 adenomas, when should you do a follow up colonoscopy
in less than 3 years
For most polyps found on endoscopy, when should a follow up colonoscopy be done?
3 years
If small tubular adenomas <10mm or sessile serrated polyps with no dysplasia are found when should a follow up colonoscopy be done?
5 years
If there are no polyps found or small hyperplastic polyps <10mm are found when should a follow up colonoscopy be done?
10 years
When do you consider that your patient might have a hereditary intestinal polyposis syndrome
- family history of CRC affecting more than one family member
- personal of family hx of CRC >50
- personal or family history of multiple polyps (>20)
- personal or familiy hx of multiple extracolonic malignancies
Which is the most common inherited colon cancer
lynch syndrome
What part of the colon does lynch syndrome typically affect? What kind of polyps does it cause?
right colon
adenomatous
What is the most common extracolonic malignancy with lynch syndrome
endometrial carcinoma
What is turcot syndrome
varient of extracolonic malignancy that affects the brain
What are the cancers/masses tested for if lynch syndrome is suspected
microsatellite instability
What is the treatment for lynch syndrome
colectomy
When are colonoscopies done in a patient with lynch syndrome
every 1-2 years starting at age 20-25
How is familial adenomatous polyposis characterized
> 100 adenomas
What other cancers does FAP increase a patients risk for
- small bowel
- gastric
- pancreatic
- thyroid
What is Gardner syndrome
FAP patients with extracolonic manifestations
What types of extracolonic manifestations do patients with FAP have
- desmoid tumors
- extra teeth or missing teeth
- congenital hypertrophy of the retinal pigment
- duodenal adenomas
- fundic gland polyps
What is the most common type of extracolonic manifestation in a patent with FAP
desmoid tumor
When does screening begin in patients with FAP
10-12 start with yearly flex sigs
How are patients with FAP treated
- prophylactic colectomy
- screen remaining rectum every 6 months- 2 years
- EGD at 20 to 25 every 1 to 3 years
- use NSADI and COX2 as chemoppx
What types of hamartomatous syndromes
- familial juvenile polyposis
- peutz jeghers polyposis
Where does familial juvenile polyposis present
- small bowel
- stomach
- colon
- rectum
What are the symptoms of familial juvenile polyposis
typically asymptomatic
can have
- painless rectal bleeding - rectal prolapse - failure to thrive
How are patients with familial juvenile polyposis screened
start at age 15 and every 1-3 years after
What things give a diagnosis of familial juvenile polyposis
- > 5 juvenile polys in the colon
- multiple juvenile polys in the GI tract
- family hx/genetic testing
What is Peutz- Jehgers syndrome
inherited GI diorders where patients develop polyps on the mucous lining of the intestine and dark discolorations on the skin and mucous membrane
How to patients with PJS present
GI bleeding, intussusceptions or obstructions
What are the most common extracolonic malignancies associated with PJS
breast and testicular cancer
What screening needs to be done in patients with PJS
- colonscopy every 2-3 years at age 18
- EGD every 2-3 years at age 10
- breast and testicular exams
How often should you do a colonscopy? flex sig? flex sig plus fit? CT colonography?
colonoscopy: 10 years
flex sig: 5 years
flex sig with FIT: 10 years
CT colonography: 5 years
How often should you do cancer detection tests? What are they?
annually
- fecal immunochemical test
- fecal occult blood test
- fecal DNA
When should cancer prevention and cancer screening tests begin?
over 50
over 45 in African Americans
When do patients stop getting screened for CRC
at age 85
When do you begin to screen patietns with a 1st degree relative w/ CRC <60 or two 1st degree relatives of any age? When do you repeat it?
40 or 10 years before family member was diagnosed
repeat every 5 years
When do you screen a patient with a personal history of CRC
-total colon examination 1 year after resection
-repeat a 3 years
if normal repeat at 5
When should you screen a patient with IBD?
8 years after onset of pancolitis, repeat every 1-2 years
Most common location for colorectal cancer
left side (rectum, rectosigmoid)
Where does colorectal cancer commonly metastasize to
lymph nodes, liver, lung, peritoneum
What are some modifiable risk factors for colorectal cancer?
- “western diet”
- obesity
- smoking
- alcohol consumption
- diabetes
What are non modifiable risk factors for colorectal cancer?
- being african american
- heriditary polyposis syndromes
- family hx
- IBD
- abdominal radiation in childhood
Symptoms of right sided colon cancer
- vague abdominal pain
- iron deficiency anemia
- fatigue/weakness
- GI bleeding
Symptoms of left sided colon cancer
- obstructive sx
- colicky abd pain
- change in bowel habits
- stool streaked with blood
Symptoms of rectal cancer
- rectal tenesmus
- urgency
- recurrent hematochezia
- narrow caliber stools
Physical exam findings of a patient with colon cancer
- rectal bleeding
- abdominal pain
What physical exam findings would indicate progressive colon cancer
- cachexia/weightloss
- back pain
- urine or bowel changes
- acites
- pallor
What tests do you need to get before you can stage colon cancer?
- CBC with diff
- LFTs
- CEA level (tumor marker)
- CT chest/abd/pelvis
- endorectal ultrasound
How many lymph nodes do you need to dissect to stage colon cancer
12
What is the treatment for colorectal cancer
- surgery: resection is treatment of choice
- chemo (stages III or IV)
- radiation plus chemo stages II-IV
What are the surgical options for colon cancer?
- laprascopic colectomy
- open colectomy
+/- ostomy
What are the surgical options for rectal cancer
- total mesorectal excision
- transanal excision
- transanal endoscopic microsurgery
- transsphincteric excision
- low anteriorrescection with colorectal anastamosis
- abdominoperineal rescection with a colostomy
Treatment of stage I colon cancer
colectomy
Treatment of stage II colon cancer
colectomy
*adjuvent therapy typically not indicated
Treatment of stage III colon cancer
colectomy + adjuvent therapy
CapeOx or 5-FU/leucovorin or folfox
Treatment of stage IV colon cancer
chemotherapy
folfox or folfiri +/- biologic
+/- resection of lung or liver met
+/- colectomy
How often is a physical exam done after surgery for colorectal cancer
every 3-6 months for two years then every 6 months for three years
When is a abd/pelvic CT done after surgery for colorectal cancer?
anually for 5 years
EXCEPT if resceted metastasis
every 3-6 months for 2 years then every six months for 5 years
When are colonoscopies done after surgery for colorectal cancer
1 year after surgery then every 3 years, can do every 5 years if negative
When are proctoscopies done after surgery for rectal cancer
every 6 months for 3-5 years
What is the most common type of anal cancer
small cell carcinoma
Non keratinizing SCC of the anus
tumors arising above the dentate line of the anal canal
Keratinizing SCC of the anus
tumors arising distal to the dentate line
What are other types of anal cancer you can get?
- adenocarcinoma
- melanoma
- sarcoma
What is anal cancer caused by
HPV
Risk factors for anal cancer
- HPV
- HIV
- genital warts
- smoking
- receptive anal intercourse
- chronic immunosuppressive conditions
Initial tests for diagnosis of anal cancer
- endoscopy with biopsy
- anoscopy
- rigid proctosigmoidoscopy
Tests for workup of anal cancer
- CT or MRI or abd/pelvis
- PET scan
- fine need aspiration or biopsy of node if noted on imaging
Treatment of stage 0-III anal cancer
neoadjuvant chemotherpay and surgery
Treatment of stage IV anal cancer
- systemic chemotherapy
- palliative chemoradiotherapy
What is the post treatment surveillance for a patient that had rectal cancer? How often is it done?
- DRE
- anoscopy
- inguinal node palpation
every 3-6 months for 5 years
+/- CT annually for three years
