Core Review GI Flashcards
Which enzyme may be elevated in pancreatic ductal adenocarcinoma?
CA19-9
Identify the following structures:

D: celiac a.
E: SMA
F: splenic v.
G: pancreas
H: distal esophagus
- Aspiration of a pancreatic pseudocyst will typically contain what?
- High levels of amylase.
Most common cause of this?

“Double duct” sign = pancreatic adenocarcinoma at the pancreatic head.
Name the most common met to the pancreas
RCC!
- 30% of all mets to panc are RCC.
- Presents as hypervascular mass-see below.
- They met quickly, i.e., w/in 6-12 mths post-presentation.
- Next most common = lung.

- What is the most common cause of this lesion in the spleen?

- Trauma. This is a simple pseudocyst.
- Splenic hematomas evolve & become liquefied seromas surrounded by a pseudocapsule.
- The cyst wall may sometimes calcify.
- True splenic cysts (lined w/epithelium) are rare & thought to be congenital.
What is the most likely etiology for these findings?

- Histoplasmosis.
- These are multiple splenic calcs.
- DDx: histo, TB, brucellosis, trauma.
- TB: usually <6 calcs, typically smaller than those in histo.
- Brucellosis: a few large rim-calcified lesions.
- When >6 calcified granulomas are seen, the most likely cause is histoplasmosis.
-
Histoplasmosis:
- Histoplasma capuslatum fungus endemic to the Ohio River Valley.
- The fungal spores are inhaled & taken up by bronchial LNs.
- They then disseminate hematogenously & some may be filtered by the spleen where they incite an inflammatory reaction, form granulomas & calcify.
Identify the following structures:

A: liver
B: stomach
C: portosplenic confluence
D: splenic vein
E: pancreatic body
F: SMA
Name the most common benign splenic tumour.
Hemangioma.

68yo female; Dx?

Dx: pancreatic serous cystadenoma.
- Grandmother tumour: grandmothers are serious!
- Benign cystic tumour.
- Often in the pancreatic head.
- Usually >6 cysts, each smaller than 2cm.
- If the cysts are small the lesion may appear solid on US.
- A central scar may be present, sometimes w/calcifications.
- Pancreatic duct dilation & parenchymal atrophy are usually not seen.
- Aspirate will not contain appreciable levels of amylase, CEA or CA 19-9.
- Mucinous cystic tumours will contain high CEA & high CA 19-9 if malignant.
Identify the following structures:

A: SMA
B: L renal vein
C: R renal artery
Name the most common primary to met to the spleen
Melanoma
These splenic findings are most commonly associated w/what process?
- Most sensitive sequence to find these?

Gamna-Gandy bodies = PHTN.
- GRE
- These are microhemorrhages which do not enhance, & contain a combo of iron, fibrosis & Ca2+.
- Found in ~10% of pts w/PHTN but can also be found in sickle cell pts.
Dx?

Angiosarcoma of the spleen & liver: complex cystic appearance w/central necrosis & irregular foci of internal nodularity.
- Can spontaneously hemorrhage.
- Early mets to liver, bone, lung.
- Assoc w/Thorostrast exposure.
What is the most common GI tract site for sarcoidosis?
Gastric antrum

If you see isolated gastric varices, what should you think of?
Splenic vein thrombosis.

Dx?

Brucellosis: solitary, large (>2cm) targetoid calcified, splenic lesion.

Name each of the structures

A: seg 7
B: seg 8
C: seg 4A
D: seg 2
E: seg 1/caudate
F: fissure of ligamentum venosum
G: seg 6
H: seg 5
I: 4B
J: fissure for falciform ligament
K: seg 3
L: interlobar fissure (for the GB, separates R & L lobes_
DDx hyperdense hepatic parenchyma

- Amiodarone
- Hemochromatosis (iron)
- Wilson disease (copper)
- Gold therapy
- Glycogen storage disease
List the LI-RADS major features favouring HCC.
- Arterial enhancement
- Washout
- Capsule
- Threshold growth

On what side of the bowel do jejunal diverticula occur?
Mesenteric

Dx?
- Do these communicate w/the biliary tree?

von Meyenburg complex: tiny T2 hyperintensities throughout the hepatic parenchyma.
- No!!!
What is the generic name for Bayer HealthCare’s Eovist?
Gadoxetate
Name 5 indications for Eovist use
- Distinguish FNH from adenoma: FNH shows early uptake & iso- to hyper on HPB phase.
- Bile leak detection: used w/MRCP to localize leaks on HPB phase.
- Assess colorectal mets burden: detects more lesions, esp <1cm than anything else.
- Assess biliary anatomy: can detect smaller order bile ducts on HPB phase.
- Screening for new HCC nodules in pts w/cirrhosis: once you’ve established a baseline MRI, it can better detect small (<1cm) HCCs.
- What is the Dx?
- Mnemonic for recalling iron vs. fat liver hypointensity on MR

- Hemochromatosis, 2dry (xsfusions): liver & spleen dark on in-phase imaging.
- Mnemonic:
- Iron on In: dark on in-phase (4.4ms on 1.5T).
- If you’re fat, get OUT! dark on out-of-phase (2.2ms).

Dx?

Hepatic AML, tuberous sclerosis: fat-signal lesion in the liver.
Dx, this finding?

THID: transient hepatic intensity difference: increased arterial flow (only seen on arterial, early PV phase) near a mass.
- Can be seen b/c of: masses, cirrhosis, PV clot, abscess/infection.
- What is a RF for malignant xformation of HCA (hepatocellular adenomas)?
- What is the % risk of xformation?
- Which is the subtype that is more common in men & at highest risk of xformation?
- MEN!
- 5-15% (it’s thought that HCAs are of hepatocellular origin).
- Beta-catenin-mutated subtype.

Dx? 30yo female, using Eovist.

Fibrolamellar HCC: T2 dark scar & mass does not enhance on delays, unlike FNH.
Most common cause of this & DDx?

“Starry-sky” = diffuse edema, acute hepatitis.
DDx: entities that cause diffuse edema/infiltration
- Toxic shock
- R heart failure
- Leukemia/lymphoma
Mnemonic for hypervascular hepatic mets

MR CT
Melanoma
RCC
Carcinoid
Choriocarcinoma
Thyroid
List the Milan criteria for pts w/cirrhosis & HCC & eligibility for liver transplant.
Milan criteria, pts must have:
- 1 HCC <5cm
- 3 HCC <3cm
- No vascular invasion in the liver, e.g., PV tumour thrombus.
- No extrahepatic mets.
The most common etiology of liver xplant graft failure?
Rejection
This mass may be associated w/what syndrome?

Giant cavernous hemangioma = Kassabach-Merritt
- Thrombocytopenia 2° to sequestration & destruction of platelets within the GCA.
- GCA size criteria: 4-10cm.
- Other GCA complications: pain, rupture, K-M syndrome.
Dx: arterial & delayed T1 Ixs w/conventional extracellular contrast.

Hepatic peliosis: delayed filling from inner to outer (opposite to hemangioma).
- Rare vascular disorder of dilated sinusoids & blood-filled cavities.
- Centrifugal pattern, unlike hemangioma which is centripetal.
- May also see this w/mets but mets will not show delayed enhancement.
- Can see this in AIDS pts b/c of Bartonella infection.
The most common cause of benign biliary stricture?
- Prior HPB surgery: 90%, and most 2° to prior cholecystectomy.
Name the structures:

- Common hepatic duct
- Proper hepatic artery
- Main portal vein

What % of UC have this?

~5% of UC pts have PSC.
Whereas ~70-90% of PSC pts have UC.
Dx: 34yo pt w/CD4 = 46/mm3.
- Most common feature of this process?

AIDS cholangiopathy, most often due to Cryptosporidium.
- 70% have papillary stenosis. Sometimes this can be in isolation.
The most common Ix presentation of GB carcinoma is?
A large mass replacing the GB (40-65%).
- This happens b/c the pts frequently present w/advanced disease.
- 2nd most common = a broad-based polyploid lesion on the GB wall.

DDx of this:

Vicarious excretion of contrast.
DDx:
- Impaired renal function: since most contrast is excreted by the kidneys but a small amount is excreted into the biliary tree.
- Higher contrast dose
- Reduced GB emptying, e.g., in the fasting state
Dx?

Schatzki ring: thickened, narrowed (<13mm) B-ring w/associated type 1 (sliding) hiatal hernia (classic association).
Dx, pt w/HIV.

CMV-related esophageal ulcer: large, flat, diamond-shaped ulcer.
Dx, 25yo male w/dysphagia & atopia.
- Tx?

Eosinophilic esophagitis: multiple concentric rings or corrugated appearance.
- Steroids; they fail Tx w/PPIs.
- High association w/food allergies.
- Also, asthma.
Name the structures:

A: pyriform sinus
B: true cord
C: false cord
D: laryngeal ventricle
Name the structures:

E: vallecula
F: epiglottis
G: laryngeal vestibule
H: trachea
List the components of normal pharyngeal phase of swallowing
- Elevation of the soft palate to seal the nasopharynx.
- Elevation & anterior movement of the hyoid & larynx.
- Adduction & apposition of the vocal cords & laryngeal closure.
- Epiglottic inversion & upper esophageal sphincter relaxation.
Dx, 65yo male, immunohistochemistry + for CD117.
- Name 2 associated conditions.

Gastric GIST: large mass w/central ulceration.
- NF-1
- Carney’s triad: (Carneys Eat Garbage) pulmonary chondroma, extra-adrenal pheo, GIST.
- CD117 = a KIT protein, specific for GIST.
H. pylori:
- Most common location for gastritis b/c of it?
- What type of Gram bacterial rod?
- What 2 entities can it cause?
- Antrum!
- Gram-negative!
- Gastric adenoca, 1° gastric (MALT) lymphoma.

- What are the borders of the Z-E gastrinoma triangle?
- Where are the gastrinomas commonly found in the triangle?
- Borders:
- Superiorly: junction of cystic duct & CBD.
- Medially: pancreatic neck/body junction.
- Inferiorly: 2/3 duodenum junction.
- 50% pancreas, 50% duodenum.

DDx?

Gastric emphysema: gas in the stomach wall.
- Emphysematous gastritis: most commonly from E. coli (60-80% mortality).
- Caustic ingestion
- EtOH abuse
- Iatrogenic: from ERCP or NG tube insertion; benign.
- COPD: when pt is coughing, but more likely in the bowel.
- Gastric outlet obstruction: can lead to intragastric pressure.
- Mucosal disruption: from ulcer/tumour.
Dx, 39yo female w/Hx of bloating & abdo pain.

NSAID-related SB stricture: thin, diaphragm-like stricture in a pt who has used NSAIDs on a long-term basis.
The most common malignancy assoc w/untreated celiac is?

T-cell lymphoma of the SB
- Most common location for GI carcinoid?
- 2nd?
- Most common site for small bowel carcinoid? PRIOR EXAM Q!!!
- Rectum-34%
- Small bowel-26%
- Ileum (prior exam Q!!!).

The most common tumour involving small bowel? (PRIOR EXAM Q!!!!)
Mets!!!
- Most commonly intraperitoneal spread from ovarian, colonic or appendiceal.
Most common cause for SBO in the US?
Adhesions
What other anomaly may arise from the same embryologic origin as a Meckel diverticulum?
vitelline duct cyst
- Both come from the omphalomesenteric duct.
- This is the embryonic communication b/w the yolk sac & developing midgut.

- What’s the name of the watershed area in the colon b/w the SMA & IMA arterial territories at the splenic flexure?
- Rectosigmoid area?
- Griffiths point
- Sudeck point

(G comes before S)
DDx of this

Colonic pneumatosis
- Bowel ischemia
- If asymptomatic:
- Meds: steroids
- Recent endoscopy, colonic insufflation or surgery
- Emphysema
- Barotrauma
- Lupus
- C. diff is what kind of bacterium (Gram-wise)?
- Which C. diff toxin produces pseudomembranous colitis?

- Gram-positive anaerobe.
- Toxin B.
T-stage?

T3: nodular projection along the L lateral rectal wall extending into the perirectal fat.

The most common cause of colovesical fistula?
Diverticulitis
What is the most common cause of large bowel obstructions?
Neoplasm.
Where is the most common site for perforation due to an obstruction from a sigmoid colonic neoplasm?
The cecum
- B/c of Laplace’s law as the cecum has the greatest diameter of any segment of colon.
Which is the most common of the hereditary colorectal cancer syndromes?
Lynch syndrome aka hereditary nonpolyposis colorectal cancer