GI and Hepatobiliary Pathology Flashcards
What are the microscopic features of a bronchogenic cyst?
pseudostratified columnar epithelium with cillia
What are the microscopic features of a duplication cyst?
Must have muscle layer! Usually squamous mucosa BQ! Closed relationship with main esophagus
What are common causes of achalasia? BQ! What organism can cause achalasia?
not common primary, usually secondary - defined by saccular dilitation - Scleroderma, Amyloidosis, Chagas - “SAC”
Organism? Trypanosoma cruzi from South America Glass side has been on board–lymphoid aggregates infiltrating myenteric plexus on glass slide
- What is the most common cause of ulceration in the GI tract?
- BQ! What anatomic location is the most common site for pill esophagitis?
- BQ! Most common medication associations with pill esophagitis/gastritis?
- Reflux (GERD) is number one cause of ulceration in GI
- This is more common mid esophagus where aorta crosses over! Expect to see ulcer with pill esophagitis–foreign material hopefully polarized or birefringent
- Iron very common etiology - esp stomach Alendronate - bone resorption
BQ! Etiology of esophageal SCC?
Tobacco, alcohol, vitamin A deficiency and zinc (aging population)
BQ! Esophageal squamous cell carcinoma can be associated with what rare autosomal dominant syndrome?
Palmaris et plantaris disseminata
Approx 1/3 will have esophageal carcinoma
What molecular alterations are found in esophageal adenocarcinoma?
Aneuploidy, loss of heterozygosity, mutation of p53, c-erbB-2 oncogene expression is present
What are the best predictors of survival for esophageal adenocarcinoma?
Depth of mural invasion, lymph node or distant metastasis
What does H pylori produce which enhances its binding to a certain blood group type?
urease and adhesion production–enhanced binding of blood Group O
What is Type A gastritis?
5% of gastritis, diffuse corporal gastritis, immune mediated (antiparietal and anti intrinsic factor Abs), high serum gastrin, F>M, low vitamin B12, H. pylori
What is Type B gastritis?
Multifocal atrophic gastritis, not immune mediated, normal or low serum gastrin, F=M, normal Vitamin B12, H. pylori 90-100%
BQ! What are some of the differences between fundic gland polyps secondary to PPI use and fundic gland polyps in someone with FAP syndrome?
PPI predisposes to fundic gland polyps, usually single or multiple, less than 1% dysplastic, have beta-catenin mutations
FAP syndrome usually multiple, large, 40% dysplastic BUT DO NOT PROGRESS to ADENOCARCINOMA usually, young patients, APC gene mutation
What is the mutation seen in Peutz-Jeghers? They have increased risk for what cancers?
Autosomal dominant, STK11/LKB1 mutation at 19p13 Increased risk for:
“PASS Boards”–Pancreatic adenoca, Adenoma malignum of cervix, Sertoli cell tumor, SCTAT, Breast carcinoma
How to distinguish inflammatory fibroid polyps from GIST?
Not cellular enough to be GIST, too many eosinophils, onionskins around vessels, CD34 positive CD117 negative except for MAST cells, usually 2-5 cm can be LARGE 11 cm, PDGFR mutation positive
What are the 3 types of gastric carcinoid and what are their associations?
Type I - type A gastritis
Type II - MEN, zollinger ellison
Type III - sporatic more aggressive, less amenable to resection, usually SINGLE, higher mitotic rate
*Type I and II are less aggressive because if you remove the gastrin stimulus, the carcinoid will go away. Sporadic ones should be treated as possibly malignant.
What are the staining characteristics of GIST?
90% positive CD117 look for MAST cells
70% CD34
20% SMA
10% S100 - not always schwannoma - LOOK For lymphoid cuffing to call it schwannoma
Criteria for grading GIST?
● Low mitotic rate: 5 or fewer per 50 HPF
● High mitotic rate: over 5 per 50 HPF
Grading
TX: Primary tumor cannot be assessed
T0: No evidence for primary tumor
T1: Tumor 2 cm or less
T2: Tumor more than 2 cm but not more than 5 cm
T3: Tumor more than 5 cm but not more than 10 cm
T4: Tumor more than 10 cm in greatest dimension
Stage IA: T1-2 N0 M0 low mitotic rate
Stage IB: T3 N0 M0 low mitotic rate
Stage II: T1-2 N0 M0 high mitotic rate or T4 N0 M0 low mitotic rate
Stage IIIA: T3 N0 M0 high mitotic rate
Stage IIIB: T4 N0 M0 high mitotic rate
Stage IV: N1 or M1
BQ! What is the most common protozoal infection in the US?
Giardia is most common protozoal infection in USA
5% of usa have it
In the world? Amoeba most common by worldwide standard 10%
What is the differential diagnosis when you see macrophages in the small bowel?
Mycobacterium avium intracellular vs Whipples
What organism causes Whipple’s disease? BQ! Where are the organisms located?
Tropheryma whipplei bacteria IN MACROPHAGES and in the lamina propria! (not only in macrophages) Stain with PAS-D!
Even patient’s after therapy will be positive so be careful! Need to use PCR to test after treatment. MAI can also be positive for PAS-D but the organisms look very different
What infectious agent is shown here ?
Cryptosporidium
BLUE BLEBS on surface of mucosa
Found in crypts, gallbladder and intestine
It is a coccidio infection usually animal infection, more in immunocompromised
What parasitic GI infection is endemic to Kentucky and Eastern Tennessee?
Strongyloides stercolaris
Can live as larval form for years, is an eosinophillic rich disease; however there are higher eosinophils in southern region anyway
hyperinfection filariform larvae - upper right
BQ! What is the Splendore-Hoeppli phenomenon?
Radiating or anular eosinophilic deposits of host-derived materials (Charcot Laden crystals) and possibly of parasite antigens, which form around fungi, helminths, or bacterial colonies in tissue
What is diaphragm disease and what causes it?
Use of slow release NSAIDS may lead to this peculiar form of strictures called diaphragm disease in the small bowel (terminal ileum)
Characterized by strips of fibrosis perpendicular to lumen
BQ! What is gluten sensitive enteropathy?
Systemic autoimmune disorder induced by exposure to gliadin or prolamin graction of gluten proteins in wheat, barley, rye, etc.
BQ! Is gluten sensitive enteropathy always a diagnosis of kids?
NO! Adults can develop it from adenovirus 12 exposure E1B protein which has alpha gliadin crossreaction–sensitizes the T cells so patient can develop gluten sensitive enteropathy
What is refractory sprue?
Celiac patients that stop responding to diet restrictions. Normal IELs should be both CD3 and CD8 positive. If the IELS are CD3+ and CD8-, sign they are developing refractory sprue which puts them at risk for EATL - enteropathy associated T-cell lymphoma
BQ! What do you see in tissue specimens from patients with Waldenstrom macroglobulinemia?
Deposit IgM in mucosa, can be PASD positive–deposits pink accellular material and Congo red neg
What is goblet cell carcinoid?
Specific to appendix, prognosis between carcinoid and adenocarcinoma - more aggressive prognosis Suggested term–adenocarcinoid, older than 30 with acute appendicitis
What is a small bowel tumor with psammoma bodies and is associated with NF1?
Pseudopsammomatous somatostatinoma
Also called psammomatous carcinoid–EXCLUSIVELY in the periampullary region
Commonly misdiagnosed as adenoCA, near ampulla of vater, glandular appearance, large
LOOK FOR PSAMMOMA BODIES
May not be somatostatin positive, physiologic effect vs stain, cut deeper - synaptophysin, neurofibromatosis I syndrome association
What 3 molecular alterations do periampullary adenocarcinomas exhibit and which of those is predictive of a short survival?
p53, c-neu (predictive of short survival) and TGF-alpha
What are the microscopic characteristics of amebic colitis?
FLASK SHAPED ULCER turns out to undermine normal mucosa not FISSURE (as in Crohn’s disease–how you distinguish).
You will also erythrophagocytosis! Organisms are Giemsa stain positive
BQ! What are the differences between MSI adenoCA and typical adenoCA?
Mucinous appearance >50% of lesion, Crohn-like response lymphoid aggregates, tumor infiltrating lymphocytes (only 2 is significant)
What is the mode of inheritance and mutated gene in Peutz-Jegher syndrome?
AD, STK11 (LKB1) at 19p13 Intestinal lesions–Hamartomatous polyps, small bowel most common Extraintestinal lesions–Up to 40% risk of CRC and >50 % risk of Breast CA. Also pancreatic and gastric CA
What is the mode of inheritance and mutated gene in familial juvenile polyposis?
AD, SMAD4 (18q21.1) or BMPR1A (10q22.3) Intestinal lesion–Lobulated hamartomatous polyps Extraintestional lesions– >50% risk of GI CA including small bowel and stomach
What is the mode of inheritance and mutated gene in Cronkhite-Candada syndrome?
TRICK QUESTION! None, No known inhertiance
Intestinal lesions– Broad based hamartomatous polyps with edema
Extraintestinal lesions–Severe disease, electrolyte imbalance and protein loss; greater than 50% mortality
What is the mode of inheritance and mutated gene in Cowden’s disease (facial trichilemmomas, acral keratosis, gastrointestinal hamartomatous polyposis)?
AD, PTEN at 10q23
Intestinal lesions– Hamartomatous polyps throughout the GIT
Extraintestinal lesions–Up to 50% risk of breast CA, up to 10% risk for thyroid CA and unknown risk of CRC
What is the mode of inheritance and mutated gene in Familial adenomatous polyposis?
AD, APC (5q21-22)
Intestinal lesions–CRC, fundic gland polyps, duodenal adenomas, and CA
Extraintestinal lesions–100% risk of CRC, Up to 5% risk of duodenal CA
What is the mode of inheritance and mutated gene in Gardner’s syndrome?
AD, APC (5q21-22)
Intestinal lesions–CRC, fundic gland polyps, duodenal adenomas, and CA
Extraintestinal lesions–100% risk of CRC, Up to 5 % risk of duodenal CA and osteomas, epidermoid cysts, fibromas, and desmoid tumors
What is the mode of inheritance and mutated gene in Turcot syndrome?
AD (66%), AR (33%), Gene is APC (5q21-22) but also involves mismatch repair dysfunction
Intestinal lesions–CRC, fundic gland polyps, duodenal adenomas, and CA
Extraintestinal lesions–PNET of CNS, Glioblastoma
To clarify:
Turcot Types: GBM + HPNCC and medulloblastoma + FAP
What is the mode of inheritance and mutated gene in Type I Lynch Syndrome?
AD Genes: MLH1 (39%), MSH2 (38%), MSH6 (6%), PMS2 (7%) (3p21.3, 2p22-p21, 2p16, 7p22) Intestinal lesions–CRC at age 50 years of age Extraintestinal lesions–None
What is the mode of inheritance and mutated gene in Type 2 Lynch Syndrome?
AD Genes: MLH1 (39%), MSH2 (38%), MSH6 (6%), PMS2 (7%) (3p21.3, 2p22-p21, 2p16, 7p22) Intestinal lesions–CRC at age 50 years of age Extraintestinal lesions–Endometrial CA, also gastric, small bowel, HCC, cholangioCA, and CA of pancreas, ovary, renal pelvis, brain, and skin
What is the triad in Plummer-Vinson syndrome?
Glossitis, esophageal webs, and iron-deficiency anemia
What is the most common site for extrapulmonary small cell carcinoma?
Esophagus
How are FAP associated fundic gland polyps different from somatic fundic gland polyps?
If FAP-related, they have been associated with somatic mutations of the APC gene with high-risk of dysplasia (up to 42%).
If sporadic, they are associated with mutations in the b-catenin gene with a low risk of dysplasia. There is a controversial association with the use of proton pump inhibitors.
What is Menetrier disease and what is the genetic mutation?
Extreme foveolar hyperplasia that spares the antrum. Patients present with abdominal pain, nausea and vomiting, and anemia (due to gastric bleeding). Hypochlorhydria results from loss of parietal cells, whereas hypoproteinemia and edema result from gastric protein loss. In adults, the disease is progressive; however, in children, it tends to resolve spontaneously and may be CMV-related. Although the etiology is uncertain, Ménétrier disease probably results from local TGF-a overproduction and increased signaling through the EGFR pathway. Preliminary evidence suggests that pharmacologic blockage of EGFR signaling is beneficial and may obviate the need for gastrectomy for intractable disease.
Which entity in the stomach has a “watermelon” appearance endoscopically?
GAVE (Gastric Antral Vascular Ectasia)
Red patches or longitudinal, nearly parallel linear streaks radiating proximally from the pylorus are identified endoscopically, imparting a watermelon-like appearance. The cause of GAVE is unknown, but it is associated with cirrhosis and portal hypertension, bone marrow transplantation, renal insufficiency, and scleroderma.
Hypertrophic gastritis: what are the 4 things in the DDx?
Menetrier’s disease, lymphoid lesions, Zollinger Ellison syndrome, and signet ring cell carcinoma
The phenomenon of duplication of the musclaris mucosa is associated with what?
Barrett’s esophagus
This is important in assessing the depth of invasion because infiltration of dysplastic glands into or between the two layers of duplicated muscularis mucosae should not be interpreted as submucosal invasion
What is Carney’s triad?
multiple GISTs, extra-adrenal paraganlioma, and pulmonary chondroma
If you see a gross picture of a tumor that is causing kinking of the mucosa which has lead to a stricture causing a small bowel obstruction, what tumor should be on the top of the differential?
Carcinoid due to the desmoplasia
Random fact: carcinoids >2cm have 90% chance of metastasizing and those <1cm have 5% chance of metastasizing
What benign neuronal tumor is seen exclusively in the duodenum (periampullary)?
Gangliocytic paraganglioma
*associated with NF1
Other than C. Diff, in what other condition can pseudomembranous colitis be seen?
ischemic colitis, Enterohemorrhagic E. coli and rarely collagenous colitis
What is shown in this GI biopsy?
Balantidium coli
What is shown in this GI biopsy?
Trichuris trichiura
What is shown in this GI biopsy?
Amebiasis
Colonic cystica profunda: when this is solitary what is the assocation and when it is multiple what is the association?
When solitary it is associated with solitary rectal ulcer syndrome
When multiple it is associated with IBD
According to 2010 Crohn’s and Colitis Foundation guidelines, when should surveillance begin following initial diagnosis of pancolitis or left-sided colitis?
8-10 years following initial diagnosis of pancolitis or left-sided colitis
A repeat colonoscopy should be performed within 1-2 years. After two negative exams, colonoscopy is performed every 1-3 years provided the duration of disease does not exceed 20 years. Current guidelines also recommend that for an adequate surveillance, a minimum of 33 biopsies should be obtained using jumbo forceps.
What organism is shown on this GI biopsy?
Giardia lamblia
Pear shaped trophozoites with two ovoid nuclei and a central karyosome.
What features are specific for ischemic colitis?
Hyalinization of lamina propria, lamina propria hemorrhage and withered/atrophic crypts are typically associated with an ischemic etiology
What flagellate organism is implicated in causing megaesophagus and megacolon?
Trypanosoma cruzi
Due to inflammatory destruction of the myenteric plexus
What primary immunodeficiency disorder results from mutation in TNFRSF13B gene and is associated with celiac disease as its most common noninfectious GI complication?
Selective IgA deficiency
*both CVID and selective IgA deficiency show mutations in this gene
All of the choices listed are categorized as secondary causes of intestinal lymphangiectasia except:
1) constrictive pericarditis
2) lymphangioma
3) mesenteric tuberculosis
4) Milroy disease
5) neuroblastoma
Milroy disease
This is primary aka hereditary lymphedema and results from congenital obstruction of lymphatic flow or presence of abnormal lymphatics. It can involve multiple organs. Patients usually present with protein losing enteropathy, malabsorption and secondary immunodeficiency. In general, secondary lymphangiectasia occurs due to cardiovascular disorders or from conditions leading to lymphatic obstruction (the other choices listed)
Which finding in a GI biopsy is specific for H. pylori gastritis?
Lymphoid aggregates with germinal centers is considered to be the most specific finding
Which segment of GI tract is most commonly involved by eosinophilic gastroenteritis?
Stomach
Eosinophilic gastroenteritis is characterized by eosinophilic infiltration within one or more segments of the GI tract along with peripheral blood eosinophilia. Most patients also have a clinical history of allergies or asthma. Stomach is the msot common site of involvement. Based on the layer of bowel wall involved, three subtypes have been described: mucosal, mural and subserosal.
The DDx of eosinophilia in the GI tract includes parasitic infections, vasculitis, collagen vascular disease, drugs, and Crohn’s disease
What protein is deleted in 55% of pancreatic carcinomas and loss of its staining supports a diagnosis of a pancreatic primary?
DPC4
Why doesn’t AE1/AE3 stain hepatocellular carcinomas and what is used in addition to help confirm this diagnosis?
AE1/AE3 does not contain CK18 and hepatocytes express CK18.
Cam5.2 is a good complement because it does cover CK18 (this is a low molecular weight keratin stain that covers CK8 and CK18
This is a lesion from the small bowel composed of nodules with pinpoint white areas. Patient’s with this lesion present with protein losing enteropathy (steatorrhea) and malabsorption (should give you that history in stem). What is it?
Cavernous hemangioma/lymphangioma
Patients with intestinal lymphangectasia present with malabsorption and protein losing enteropathy
In fibrous obliteration of the appendix, what do the spindle cells stain for?
S100
Therefore this process has also been referred to as neural hyperplasia or neuroma
What is the most common parasitic infection of the appendix?
Enterobius vermicularis
The hyperplastic gastropathy in Menetrier’s disease is from excessive secretion of what?
Transforming growth factor alpha (TGF-alpha)
Which lymphoma most commonly presents as lymphomatosis polyposis of the GI tract?
Mantle Cell Lymphoma
Ileocecal valve region tends to contain the largest number of polyps
In Cowden’s syndrome, besides hamartomatous polyps, what other GI lesions are common?
Colonic lipomas, fibrolipomas, fibromas, ganglioneuromas, and adenomas
In sessile serrated polyps, what genetic mutation do most of them harbor?
Most show BRAF mutations and show a high rate of DNA methylation
MSI is usually not associated with these lesions unless they develop epithelial dysplasia or carcinoma
What autosomal recessive syndrome is from a germline mutation in a gene associated with DNA base pair excision repair and results in numerous colon polyps and colon cancer?
MUTYH associated polyposis (MAP)
MUTYH is part of the DNA base excision repair system that protects genomic information from oxidative damage. MAP is a hereditary colon cancer syndrome inherited in an autosomal recessive pattern. It is caused by biallelic mutations in the MUTYH gene. Usually, the MUTYH gene product excises adenine bases from DNA at sites where adenine is inappropriately paired (such as with guanine or cytosine). When the MUTYH gene product is impaired by bi-allelic germline mutation, it leads to the mutation of cancer-related genes, such as APC, from inappropriate G:C to T:A transversions. The clinical features of MAP include 10-100 adenomatous polyps in the colon, and early onset of colorectal cancer. MAP is currently the only known recessive hereditary colon cancer syndrome. Approximately two-thirds of colon cancers in MAP are right-sided.
What genotype accounts for >85% of the cases of hereditary hemochromatosis?
One genotype (C282Y/C282Y) accounts for >85% of all cases of hereditary hemochromatosis (HH)