Colorectal Flashcards
MC cause of death after TAC in FAP
How to prevent
duodenal adenomas and adenocarcinoma.
Prevention includes regular upper esophagogastroduodenoscopy every 2 to 3 years @ 20-25 YO
How to monitor anal tissue after TAC in FAP?
Regular procto with Bx
surveillance after TAC with IPAA in FAP?
q1 year vs q2 (elevated risk for rectal recurrence)
score says q1yr endoscopy
when to perfrom an IPAA after proctocolectomy
6 mos at least.. still need a DLI x 6-8 wks fr IPAA to heal
FAP surveillance?
Flex proctosigmoidoscopy @10 to 12 years (repeated every 1-2 years until age 35 and every 3 years thereafter)
Upper endoscopy every 1 to 3 years once polyps are identified
Cowden disease surveillance?
PTEN mutation (hamartoma dz)
Clinical thyroid examination (annually)
Mammography annually beginning at age 30 or 5 years before earliest breast cancer diagnosis in family members
Routine colonoscopic surveillance
Peutz Jeghers syndrome surveillance
HAMARTOMAS
Upper endoscopy
Small bowel radiographic study
Colonoscopy (every 2 years)
Pancreatic ultrasound (annually)
Gynecologic examination with pelvic ultrasound
Mammography annually (beginning at age 25)
CDH1 mutation (e-cadherin)
hereditary diffuse gastric cancer and increased risk for breast ca
when to ppx gastrectomy in hereditary diffuse gastric ca?
20-30 YO
Lynch syndrome = hereditary nonpolyposis colorectal ca
ADominant. DNA mismatch repair = MLH1, PMS2, MSH2, and MSH6.
A deletion in the epithelial cell adhesion molecule, which results in MSH2 promotor methylation, can also cause HNPCC.
how to dx HNPCC
AMSTERDAM CRITERIA.
3+ family members with CRC (1 first degree)
2+ generations
1 <50 YO
what kind of cancers pop up in HNPCC?
RIGHT sided colon cancer
Endometrial tumors
Ovarian tumors
Stomach ca
Urinary tract ca
Small bowel ca
CNS ca
APC somatic vs germline mutations
somatic: in more than 80% of sporadic colon cancers
germline: cause familial adenomatous polyposis (FAP).. TSG regulates intracytoplasmic B-catenin
HNPCC screening?
Colonoscopy at age 20 to 25 years (repeated every 1-3 years)
Transvaginal ultrasound or endometrial aspiration (females) at age 20 to 25 years (repeated every year)
colorectal met chemotherapy
bevacizumab, fluorouracil, and oxaliplatin/irinotecan
or FOLFOX (leukovorin, fluoro, oxali)
early stage rectal ca transanal excision margin
1cm; full thickness
rectal ca staging ERUS vs MRI
MRI is much better at detecting mesorectal fascial involvement for CRM (CIRCUMFERENTIAL MARGIN = important PROGNOSTIC indicator)
colon ca postop chemo indication
node positive or M1 AKA… .STAGE III AND ABOVE.
FOLFOX 6 mos (or 3/3)
primary peritoneal mesothelioma
2/2 asbestos
50+ YO
M>F
staging of primary peritoneal mesothelioma
The T-stage based on peritoneal cancer index (PCI) - size and distribution of the tumor
T1 is a PCI score of 1-10
T2 is a PCI score of 11-20
T3 is a PCI score of 21-30
T4 is a PCI score of 31-39.
T1N0M0 disease is classified as stage I disease
T2-3N0M0 is classified as stage II disease
stage III disease is any T4 disease, or any T1 or greater disease with the presence of node-positive or metastatic disease
mgmt primary peritoneal mesothelioma
HIPEC / CRS
pseudomyxoma peritonei mgmt
CRS HIPEC - does not travel lymphatically so can just do an appendectomy and not a R hemi
2.5mm nodules all removed; if cannot get <2.5mm, don’t do HIPEC (no survival benefit)…
NOT radiosensitive.
rectal carcinoid tumor mgmt
Transanal excision is adequate for tumors less than 2 cm in diameter
Proctectomy would be indicated with mesorectal excision for larger lesions (> 2 cm).
Invasion of the muscularis propria (T2) has been associated with lymph node metastases in up to 47% of patients.
Systemic chemotherapy is used in metastatic carcinoid lesions; however, its efficacy is limited
colon carcinoid mgmt
<1cm polypectomy
>1cm formal resection
Postop surveillance after oncologic colon cancer resection?
CEA every 3 to 6 months
CT chest/abdomen/pelvis every 6 to 12 months
Colonoscopy at 12 months
indications for proctocolectomy with or without IPAA in ULCERATIVE COLITIS
colorectal cancer, a non–adenoma-like dysplasia-associated lesion or mass (DALM), or high-grade dysplasia
which sx get better after colectomy in UC?
anemia, uveitis, arthritis, episcleritis improve
50% pyoderma gangrenosum, erythema nodosum
which sx do not get better after colectomy in UC?
PSC and ankylosing spondylitis
how long should an ileal J pouch be?
15-20 cm
what mutation associated with IBD
NOD2, HLA B27
pelvic floor dysfunction causing constipation
dx and mgmt
Sitzmarker study (distal accumulation) combined with an abnormal defecography or functional MRI
physical therapy and biofeedback training to retrain the pelvic floor muscles to relax properly to allow for normal defecation.
mgmt of toxic megacolon in UC
total colectomy without proctectomy (damage control) with end ileostomy
(can trial medicien first (NGT, fluds, steroid, bowel rest, CTX/Flagyl))
UC presentation
bloody diarrhea, pain, weight loss (less than Crohns)
UC dx
path colonoscopy = pseudopolyps, collar button ulcer, crypt abscesses, anal sparing
UC screening
8 years after dx, every 1-2 years
All abnormal lesions must be biopsied along with random biopsies performed in 4 quadrants every 10 cm along the colon and rectum
Crohns screening
8 yrs after dx q1yr
Surveillance should be performed using either random biopsies or chromoendoscopy every 1 to 3 years or more frequently if mandated by findings
MC site of perforation UC vs Crohns
transverse colon vs distal ieum
2cm+ mass on appendectomy
hemi
MC extraintestinal manifestation of UC requiring colectomy
FTT
mgmt of colovesical fistula with fecaluria presentation
- abx
- let all inflammation subside
- colectomy with fistula takedown, bladder closure, omentum interposition between colon and bladder
Gardner (desmoids and polyposis) encounter mesenteric desmoid during colectomy
core bx it; don’t resect (will end up resecting more than you should… short gut)
Crohn’s disease pathology on Bx
transmural involvement, segmental disease (skip lesions), cobblestoning, narrow ulcers, creeping at, GRANULOMAS
mgmt of Crohn’s maintenance
sulfasalazine, loperamide
refractory: remicade/infliximab (TNF-a inhibitor) good for fistulas
mgmt of Crohn’s acute
steroids
surgery in Crohn’s
NOT curative (unlike UC)… no LIS for fissure, no takedown of fistulas I.e.
rly only indication:
blind loop obstruction
anorectal advancement flap vs colostomy in anorectovaginal fistulas
strictures (see other card)
if resecting in Crohn’s, margins?
2 cm away from gross disease
severe colonic disease in Crohn’s necessitating surgery
proctocolectomy and ileostomy is procedure of choice
NO POUCHES/IPAA In CROHNS
incidental Crohn’s disease when suspected appy
take out appy (will confound in future)
stricture disease in Crohn’s
MC is resection if SHORT ISOLATED SEGMENT
consider stricturoplasty if impending short gut
<10cm: (longitudal incision close transversely = Heineke-Mikulicz)
10-20cm: FINNEY (fold stricture segment and make common channel
>20cm: MICHELASSI: same as finney but longer
Make sure to Bx if stricturoplastying
CI to stricturoplasty: malnutrition, presence of inflammatuion/fistula, malignancy
MC complication after stricturoplasty?
bleeding! not perf/restricture interestingly
;.;;oxalate stones in Crohn’s s/p TI resection
decrease oxalate binding to Ca 2/2 increased intraluminal fat
oxalate goes into colon
released in urine
ca-oxalate kidney stones
Rectal prolapse management
high fiber diet
if old/sick: Altemeier = perineal rectosigmoid resection transanally - HIGHER RECURRENCE, LESS DURABLE
if can tolerate: transabdominal rectopexy (open vs lap) +/- LAR or sigmoidectomy if CONSTIPATION concurrent.
What is positive node
0.2 mm of cancer deposit
circular layer of muscle in colon?
muscularis PROPRIA
what is haustra?
transverse bands made up of plicae semilunares
taenia coli
3 bands; splay at rectosigmoid junction
quick measurements from verge
dentate
end of rectum
\every 1/3 of rectum
top of rectum
dentate 2 cm
end of rectum 4 cm (where levator ani is)
thirds of rectum split by 4 cm16 cm
middle rectal artry origin
internal iliacs** but follows portal venous flow
inferior rectal artery origin
pudendal from internal iliac
superior/middle rectal VEINS drain into
IMV to portal
inferior rectal vein drains into
internal iliacs and then cava system
superior and middle rectum VS inferior rectum nodal drainage
superior/middle = IMA nodes
inferior = IMA and internal iliacs
below dentate = internal iliacs
external sphincter muscle & innervation
puborectalis (continuation of levator ani) mm AND internal pudendal nerve (voluntary)
internal sphincter muscle and innervation
smooth muscle cotinuation of muscularis propria… AND pelvic splanchnic nerves (involuntary)
plexus of colon wall
Meissners plexus INNER
Auerbachs plexus OUTER
pelvic splanchnics para vs sympa?
PARA.
crypts of Lieberkuhn
mucin secreting goblet cells in rectum
pouchitis abx of choice
flagyl (and cipro),
consider budesonide enema if persistent
if intractable, consider Crohns; and resect. end ileostomy 4 life.
denonvilliers fascia
ANTERIOR fascia; rectovesicular/rectoprostatic/rectovagial fascia
waldeyers fascia
POSTERIOR fascia; rectoSACRAL
cancer risk with villous adenoma
50% have cancer
polyp high risk features
> 2cm
villous
sessile
carcinoma in situ vs high grade dysplasia? in colonic polyp
THE SAME THING.
definition of invasive colon cancer
invades submucosa (T1)
COLON CANCER screening recommendations
@50, q10yr - colonoscopy or @50, q5yr sigmoid + FOBT
or @40 q5yr or 10 yr before earliest dx if first degree family hx*
Or @40 q10yr if first degree > 60YO or two 2nd degree
Or @10-12 YO q1yr sigmoidoscopy FAP
Or @20-25 YO q1-2 yrs or 10 yrs before dx HNPCC
alternative to colonoscopy surveillance
fecal occult blood test q3yr with flex sig q5yr
OR
fecal occult blood test q1yr
polypectomy shows T1 lesions (villous or nonvillous)
all good! as long as 2mm margin & well differentiated
low rectal villous polyp that shows T2 lesion*
APR or LAR
colon ca bacterial association
Clostridium septicum
genetic mutations with colon ca
APC
DCCC
p53
KRAS
most important prognostic factor colon ca
NODAL STATUS
batsons plexus
in breast AND rectum (spine mets… but colon doesn’t rly go to spine)
lymphocytic penetration in colon ca
better** prognosis
worst prognosis type of colon ca
mucoepidermoid type
rectal cancer resection goals
2 cm margin
rectal ca mgmt
T1: excise if <3cm, <1/3 circumference, close to verge; otherwise APR/LAR
otherwise surgerize
NEOADJUVANT:
Stage II and III: chemoXRT 5000 cGy with 5-Fu to make radiosensitive x 5-6 wks
Re-image for response.
SURGERY:
Upper 1/3: mesorectal excision with 5cm distal margin (like colon)
Lower 2/3: total mesorectal excision with LAR or APR, 2 cm distal margin; 1cm if very distal otherwise need APR
ADJUVANT: FOLFOX
for Stage III or higher who did not get NEO (were understaged)
for high risk Stage II (high grade)
Stage IV: chemoXRT +/- SURGERY (maybe just colostomy)
TNM staging colon and rectal ca
T1: into submucosa
T2: into muscularis propria
T3: into subserosa or thru propria if no serosa present
T4: through serosa into free cavity/adjacent organs if no serosa present
N0: none
N1: 1-3 positive (0.2mm deposit of cancer cells)
N2: 4+
N3: central nodes positive
M1: distant metss
staging based off TNM
0: TisN0M0
I: T1-2N0M0
IIA: T3N0M0
IIB: T4N0M0
IIIA T1-2N1M0
IIIB T3-4N1M0
IIIC anyTN2M0
IV M1
colon ca mgmt
All resectable: 3 mo FOLFOX then surgery then 3 mo FOLFOX
III and IV: adjuvant chemotherapy (NO RADIATION)
5 cm margin, 12 nodes
f/u colonoscopy after cancer resection?
1 yr to look *for another primary
Amsterdam criteria for Lynch syndrome 321
3 first degree relatives
2 generations
1 cancer < 50 YO
surveillance start in Lynch
@25 YO or 10 years before relative
mgmt Lynch
total proctocolectomy
sigmoid volvulus dx and mgmt
XR RUQ pointed
decompress with colonoscopy if not peritonitic - leave tube 1-3 days (high rate recurrence)
perform OPEN sigmoid colectomy primary anastomosis same admission
If unstable: HARTMANNS
cecal volvulus dx and mgmt
XR LUQ pointed
20-30 YO
just go to OR for R hemi or ileocecectomy > pexy
Do not decompress!
Ogilvies mgmt
if colon > 12 cm or >6 days (high perforation risk)
tx:
1. fluid resuscitation, correct lytes, NGT decompression
2. neostigmine (AE: bradycardia)
3. cscope decompression if neo fails
4. if no improvement @ 6 days, R hemi vs subtotal
If just failed obs, just tube cecostomy vs resection
If ischemia/perforation: OR resection (anast can be considered)
travel to Mexico presents with bloody diarrhea
dx: endoscopy with ulceration/trophozoites, 90% have E.histolytica Abs
mgmt: Flagyl, diiodohydroxyquin
azotemia after GIB
urea from bacterial action on intraluminal blood. increase BUN and Total BILi
arteriography speed of bleeding
at least 0.5 cc/min
Tagged RBC study speed of bleeding
at least 0.1 cc/min (so wont see it on CTA again. just embolize)
divertiular bleeding cause
vasa recta (arterial bleeding) disruption
angiodysplasia in colona
mostly RIGHT
associated with aortic stenosis (improves after valve surgery)
cold vs hot snare polypectomy
cold in general… push in and pull
hot if: 1cm+ sessile/pedunculated polyp
otherwise use cold.
Length of colon and rectum
5-6 ft, 15cm rectum
Arc of riolan vs marginal; which is closest to the colon WALL (SMA IMA connection)
Marginal is closer.
Middle colic artery vs RIGHT/LEFT
Middle colic perfuses 2/3 of transverse; left takes over distal 1/3 to descending.
Watershed areas
Splenic = GRIFFITHS SMA/IMA connection
Rectosigmoid = SUDECKS Sup/middle rectal aa
Rectum boundaries
Prox: where taenia SPLAY [colaesce at the cecum]
Distal: ANAL CANAL (15cm from verge)
Anal canal boundaries (15 cm, like rectum)
Prox: puborectalis sling (anorectal ring)
Distal: the verge
Define the anal margin
5cm radially from VERGE (squamous mucocutaneous junction)
Diverticulitis - Hinchey classification
I: Pericolic abscess < 4 cm
II: >4 cm
III: Purulent peritonitis
IV: Feculent peritonitis
“Complicated” diverticulitis
Perforation (not just extraluminal gas or phlegmonous changes)
Abscess
Fistula
Obstruction
Stricture
So… Hinchey Ib or higher.
Treatment of complicated diverticulitis?
II: perc drainage
III, IV: Hartmann’s
Timing of colonoscopy (if not recent) after resolution of uncomplicated divertiulitis?
6 wks - to r/o underlying ischemia, IBD or neoplasm
Elective colectomy in diverticulitis?
Complicated - resolved: Yes. Offer.
Uncomplicated: not necessarily higher risk of emergent colectomy/stoma so can consider individual basis.
C. diff dx
send stool PCR: Ag and toxin B
C. Diff treatment
PO vanc, alt: fidaxomicin, flagyl
Fidaxomicin: PO marolide
How to change surveillance based on scope findings?
1-2 tubular adenoma: 5 years
>3 tubular adenomas: 3 years
ANY Advanced (>1 cm, HIGH GRADE, dysplasia, VILLOUS): 3 years
Hyperplastic polyps: 10 years (average risk)
How to change surveillance based on scope findings?
1-2 tubular adenoma: 5 years
>3 tubular adenomas: 3 years
ANY Advanced (>1 cm, HIGH GRADE, dysplasia, VILLOUS): 3 years
Hyperplastic polyps: 10 years (average risk)
Colon cancer resection goals?
5-7cm margins, 12 nodes
high quality colonoscopy
90%+ CECUM INTUBATED
6 MINUTES withdrawal
perforation rate <.1 in 1000 screening, <1 in 500 overall
<1% post polypectomy bleeding
post polypectomy bleeding is ok nonop in 90+% cases
postpolypectomy syndrome
full thickness without perforation after thermal injury
return with fever and pain
tx: obs, exams, bowel rest, IVF, abx
colonic lipoma
pillow sign
resect if sx or > 2 cm
abx ppx to prevent SSI in SCIP for elective colon surgery
(clean contaminated)
cefoxitin/erta/ancef+flagyl within 1 hour
PREP = 1 g neomycin + 1 g erythromycin (or 500 flagyl) PO 18 hr, 17 hr, and 10 hrs
amifostine
IV infusion to prevent radiation enteritis
fecal incontinence from babies
probably sphincter defect; get ENDOANAL US FIRST TO DX
tx: overlapping sphincteroplasty
clinical presentation radiation enteritis/proctitis
ACUTE: n/v, pain, diarrhea within 6 wks
CHRONIC: obstruction, pain, diarrhea, bleeding in 8-12 mos
mgmt radiation enteritis/proctitis
ACEi, statins, AMIFOSTINE********
hnpcc with sebaceous gland tumors + GU cancers
MUIR-TORRE SYNDROME
hnpcc screening
20 YO c scope
30-35 EGD and UA
25 endometrial vacuum curettage
appendiceal carcinoid (NET) mgmt
> 2 cm needs hemi
positive margin
LV invasion
positive margin
3 mm mesoappendix invasion
ALL NEED HEMI
appendiceal ADENOcarcinoma mgmt
hemi
serosa
not on rectum; yes on colon
typhlitis dx
WBC < 3…. can mimic surgical emergency with pneumatosis intestinalis (not an indication alone for OR!!!!!!0
typhlitis tx
Abx… get WBC up…. surgery ONLY for free perforation
what GI bug looks like appendicitis
Yersinia
Yersinia tx
tetracycline or Bactrim
