Colon Flashcards
a growth on the inner surface of the colon is referred to as
a polyp
some polyps undergo what type of transformation?
malignant transformation, others do not
types of colon polyps
pedunculated which are attached by stem or stalk
sessile which are flat
three type of colon adenomas? which of these is most common
tubular adenoma, the most common
tubulovillous adenoma
villous adenoma
which types of colon polyps are neoplastic (precancerous)
adenomas (2/3 of all colon polyps), and sessile serrated adenomas
which types of colon polyps are non-neoplastic
hyperplastic and pseudopolyps (associated with inflammation/ IBD)
large polyps may
bleed
70% of ________ arise from adenomas
colorectal carcinomas (CRC), this takes about 10 years therefore early detection and removal is key
what is considered an advanced adenoma (3 criteria)
greater than 10 mm, villous component, high grade dysplasia
what increases the risk of colorectal cancer
the number of adenomas, the size, and the histology
malignant growth on the inner wall of the colon and/or rectum is called
colorectal cancer
over 95% of colorectal cancers are
adenocarcinomas
what is the non screen rate
1/4 of adults aged 50-75
pertaining to colorectal cancer, what are the left side and right side differences
left side is most common, but right side is on the rise
risk factors for colorectal cancers (9)
age personal or family history IBD after 8 to 10 years African American Smoking ETOH diet obesity diabetes
diet factors for colorectal cancers risk
high fat low fiber
increased amounts of red and processed meats
colorectal cancer red flags (5)
changes in bowel habits hemattochezia IDA (iron deficiency anemia) anorexia or weight loss abdominal pain
colorectal cancers patients are often?
asymptomatic, why screening is important
when presenting with symptoms what are the common colorectal cancers presentations
cachectic, pallor of the skin, lymphadenopathy, abdominal distention, ascites, mass, oragnomegaly, positive hemocult, rectal mass
colorectal cancer- why are we performing a CBC?
used to check for IDA due to chronic blood loss
colorectal cancer- what abnormalities may be seen on a liver function test?
Alk phos may be elevated with liver metastasis
what is CEA used for and what is it not used for?
can be a helpful prognostic indicator and allow for monitoring for recurrence, it is not used for screening
what test. allows for both biopsy and pathologic confirmation?
colonoscopy
why would you order a chest/abdominal/ pelvic CT when assessing for colorectal cancer?
to asses for tumor extension or complication, regional lymphatic metastases and distant metastases
what type of lesion is classic on colonoscopy for colorectal cancers
a classic apple core lesion
what is the colectomy management of colorectal cancers
Partial colectomy with wide margins and adjacent lymph node removal
when is chemotherapy used for CRC treatment
use when metastasis are present
when is radiation therapy commonly used for CRC
rectal adenocarcinomas
CRC surveillance consist of what 3 things
serial CEA levels
annual surveillance CT
periodic colonscopy
gold standard for CRC screening
colonoscopy, it is both diagnostic and therapeutic
In what way is a colonoscopy therapeutic?
Able to detect and remove polyps to PREVENT them from turning into cancer
Post polypectomy surveillance interval depends on endoscopist recommendations, size number, histologic features
complications of colonoscopy
perforation/bleeding
what can influence results of a colonscopy
bowel prep and operator skill
flex sigmoidoscopy reaches, this causes limited detection of what area?
the distal 1/3 of the colon, lower benefit in protection again right sided colon cancer
if a polyp is found on a flex sig, what is the next step?
They will then need a colonoscopy to rule out proximal lesions
Which less invasive test can miss flat or smaller polyps (less than 6 mm)?
CT colonography
gFOBT sensitivity and use
sensitivity for one time screening is not ideal, annual use is recommended which can influence compliance
diet modifications of gFOBT (what food must be avoided)
avoidance of red meat, iron supplements, Vitamin C and NSAIDS
what are the 3 stool based screenings
gFOBY, FIT, abd FIT DBA
When do we start CRC screening in IBD patients
8 to 10 years after onset of symptoms
when to start CRC screening in patients with Single 1st degree relative w/ CRC or documented advanced adenoma dx > 60 y/o
age 40 and if it is normal screen as average risk
when to start CRC screening in patients with Single 1st degree relative w/ CRC or documented advanced adenoma dx < 60 y/o or ≥ two 1st degree relatives dx at any age
Colonoscopy every 5 years beginning at age 40 or 10 years younger than the age at which the youngest 1st degree relative was diagnosed
whichever comes first
Which colorectal cancer screening test is used in individuals with increased risk?
colonoscopy
which condition is autosomal dominant with a mutation in the APC gene? what does this put them at an increased risk for?
Familial Adenomatous Polyposis, Increased risk of extracolonic malignancies
how many adenomatous polyps are common in Familial Adenomatous Polyposis? What age do these polyps being to form?
over 100, they typically begin at age 16
with Familial Adenomatous Polyposis, nearly all of them will develop what by age 39? How do we manage this risk?
CRC, therefore a prophylactic colectomy is typically recommend
4 examples of increased risk of extracolonic malignancies which Familial Adenomatous Polyposis
Gastric/Duodenal/Ampullary carcinoma
Follicular or Papillary thyroid cancer
Hepatoblastoma
CNS tumors
screen for these with FAP Screening
FAP screening
Sigmoidoscopy/Colonoscopy starting at age 10-12 and repeating every 1-2 years
Routine EGD recommended
what is “Lynch syndrome”
Hereditary NonPolyposis Colon Cancer (HNPCC), multiple family members will be affected
Hereditary NonPolyposis Colon Cancer patients have an increased risk for what? and at what age?
for CRC (usually right-sided); aged 45-60 years and other cancers
what is the most common additional cancer for Hereditary NonPolyposis Colon Cancer
Endometrial cancer
Hereditary NonPolyposis Colon Cancer 321 rule (Amsterdam criteria)
3 relatives associated with Lynch syndrome associated cancer, 2 successive generations affected and 1 should be diagnosed before age 50
Hereditary NonPolyposis Colon Cancer screening
Annual colonoscopy beginning between the ages of 20-25
or 2-5 years prior to the earliest age of CRC diagnosis in the family (whichever comes first)
other exams for patents diagnosed with HNPCC
pelvic exam with endometrial bx and transvaginal US
any screening regime is better than _________?
nothing, but advised patients that colonoscopy is required for further evaluation if anything is found on the less invasive test
diet modifications to decrease CRC risk (6)
encourage fiber rich foods limit red and processed meats limit ETOH (1-2 savings a day) exercise maintain healthy body weight stop smoking
pseudopolyps are associated with what condition?
IBD
