Gi Pathology Board Review

Front 1

Infant with poor feeding and respiratory distress

Rads show esophageal duplication

1. % of all duplication in GI

2. when does problem occur?

3. Micro?

Back 1

1. 10-20%, mostly in lower esophagus

2. 5-8th week gestation

3. Cyst in muscularis propria with squamous, cuboidal, or ciliated epithelium. If cartilage, then it's a bronchogenic cyst

Front 2

Patient with dysphagia, regurgitation, halitosis, or neck mass. "gurguling" sound on swallowing.

Located at level of pharyngoesophageal junction

Micro: Cystic structure composed of all layers of the esophagus with attenuated muscle layer. Mucosa may be inflamed or ulcerated.

Back 2

Esophageal diverticulae, including Zenker's

Occur at triangle of Killian

0.3% chance of malignancy

Front 3

Young adults with severe dysphagia and chest pain that is progressive.

Micro: loss of myenteric plexus- chronic inflammation around ganglion cells.

Back 3

Achalasia

Front 4

Patient with heartburn, may have chest pain, asthma, or hiccups

Micro: 2 forms: A: esophagus with intraepithelial edema with areas of necrosis and balloon cells, and intramucosal lymphocytes, B: basal cell hyperplasia, elongated papillae, intraepithelial eosinophils

Back 4

GE reflux esophagitis (GERD)
A: acute, B:chronic

11% of the population

LES dysfunction

Front 5

Young patient with h/o eczema, food allergies, asthma; presents with feeding difficulties or dysphagia (in older children or adults)

Gross: Endoscopic: esophageal mucosal rings, furrows, granularity.

Micro: marked eosinophilic infiltrate, concentrated in luminal aspect, may form microabscesses. Basal zone hyperplasia, elongation of papillae.

DX criteria?

Back 5

Eosinophilic esophagitis

Must see 20 Eos/HPF

Front 6

Most common esophageal infections (in order)?

Typically in the immunocompromised patient.

Gross: 1. numerous white plaques that may obstruct the lumen. 2. Numerous ulcers. 3. Deep ulcers covered by yellow exudate

Brushings allow for Dx

B: Micro: What is a Cowdry A/B inclusion?

C: What cells are most affected in CMV?

Back 6

1. Candida 2. HSV 3. CMV

B: Cowdry inclusions are red intranuclear inclusions with a halo in HSV

C: endothelial and mesenchymal cells

Front 7

1. Features of radiation esophagitis?

2. How long after therapy is it seen?

Back 7

1. atypial with bizzare elnaged cells, preserved N/C ratios. vacuolated cytoplasm and pale nuclei. Multinucleation.

2. 2 weeks for injury, chronic form= strictures in 13-21 months

Front 8

Middle aged man with dysphagia or mass in neck

Gross: sausage-like pedunculated polyps in the wall of the esophagus

Micro: histologically uniform lesion comprised of admixture of mature adipose tissue lobules, prominent vasculature, fibrous stroma

Back 8

Fibrovascular polyp

Front 9

incidental distal esphageal endoscopic lesion

Gross: tiny polyps

Micro: bland polypoid squamous mucosa with fibrovascular cores

Back 9

Squamous papilloma

NOT associated with HPV

Papillomatosis in the larynx/trachea IS associated with HPV, see classic features

Front 10

middle aged white man with h/o GERD, hiatal hernia

Gross: edoscopy- tongues and patches of salmon colored mucosa.

1. Important distinction in gross?

Micro: Replacement of squamous epithelium with columnar epithelium- see intestinal metaplasia. May see dysplasia

SS: Alcian blue highlights goblet cells.

2. How is dysplasia graded?

IHC: CK7/20, CDX2
3. Markers for dysplasia?

Back 10

Barrentt's esophagus

1. length of involvement- short segment <3cm, long segment >3cm. Long segement has higher risk for CA

2. 4 features- surface maturation, architecture, cytologic features, inflammation; look for:
LGD- loss of surface maturation with architectural distortion (glandular crowding), but no marked cytologic atypia. Minimal inflammation.
HGD- lack of surface maturation, marked architectural distortion (cribiform, loss of intervening lamina propria), cytologic atypia= hyperchromatic with nuclear membrane irregularities and enlarged. Loss of nuclear polarity. minimal inflammation

If high inflammation, favors indeterminant for dysplasia

Intramucosal carcinoma defined as invasion into the LP, not through muscularis mucosa.

3. p53, Ki-67

Front 11

White man with h/o Barrett's presents with weight loss and dysphagia/odynophagia.

Gross: firm white mass in the distal esophagus in salmon-colored mucosa

Micro: malignant cells with glandular differentiation

1. % of barrett's patients that get it?

2. Other disease risk factors?

3. T staging

Back 11

Esophageal adenocarcinoma

1. 10%

2. white, man, obese; smoking, alcohol

3. T1- submucosa, T2- muscularis propria; must be within 5 cm of the GE junction

Front 12

African American man with h/o smoking and alcohol use presents with dysphagia, odynophagia, and weight loss

Gross: middle third of esophagus, firm white mass

Micro: invasive nests of cells with keratinization

1. Risk factors?

2. IHC

Back 12

Squamous cell CA

1. AA men, alcohol+smoking, then anything that irritates the mucosa (diverticulae, acalasia). also deficiency syndromes- Plummer-Vinson

2. CK5/6. p63

Beware spindled variants! R/O melanoma (can be primary!)

Front 13

Mesenchymal tumors that can arise in the esophagus?

Back 13

1. GIST
2. leiomyoma
3. granular cell tumor (1% of these)
4. neural tumors

Front 14

Patient present with acute onset of abdominal pain vomiting, GI bleeding

Gross: endoscopy- multiple gastric ulcers 2-5mm, round, dark.

Micro: range from subepithelial hemorrhage to mucosal sloughing and necrosis, neutrophil infiltration. Limited to mucosa.

1. associated history?

Back 14

Erosive gastritis

1. Aspirin, NSAIDs, steroids, alcohol, KCl, iron pills, Kayexelate, "cushing ulcers" (stress) hypoperfusion injury

Front 15

Patient with vague upper GI pain, nausea, vomiting, GI bleeding; h/o chronic NSAID use, smoking, drinking

Gross: gastric erosions or erythema

Micro: Antrum with foveolar hyperplasia with villiform surface and tortuous gastric pits "corkscrew". May show mucin depletion, nuclear enlargment without atypia, vascular congestion, SM proliferation. Focal erosions with eos or polys seen. Paucity of inflammatory cells

1. Important R/O for DX?

Back 15

Chemical (reactive) gastritis

1. H.Pylori organisms- both present with foveolar hyperplasia.

Front 16

AA/Asian with abdominal pain, nausea, vomiting, iron deficiency, GI bleeding

Gross: gastric erythema, nodularity, erosions.

Micro: antral and body mucosa with prominent superficial mucosa inflammation (mixed). Crypt absecesses seen. Foveolar hyperplasia. Erosions/hemorrhage, lymphoid follicles common. Small, "seagull" organisms in crypts.

IHC- organisms highlighted with WSS/immuno

1. Associated with what DZs(2)?

2. prevalence?

Back 16

H. Pylori gastritis

1. PUD (60%), MALT lymphoma. Next most common cause of PUD is NSAID use.

2. Worldwide 50%, 1st world 30%, poor- 75%

Front 17

Woman (3:1) with abdominal pain, weight loss, pernicious anemia, elevated serum gastrin. H/o DM, thyroiditis

Gross: Gastric body and fundus red and shiny. May have "pseudopolyps".

Micro: chronic gastritis (lymphoplasmacytic infiltrate in LP), loss of oxynic glands, pseudopyloric metaplasia, and intestinal metaplasia. May have pancreatic metaplasia. Antrum has gastrin cell hyperplasia.

1. Affected cell types and molecules?

2. Assc. with what tumor?

3. How do you know where you are in the stomach?

Back 17

Autoimmune gastritis

1. Antibodies against parietal cells and intrinsic factor. Loss of parietal cells results in hyper gastinemia.

2. Carcinoid tumor (2-9%), 2-3x risk of adenoCA

3. Gastrin IHC should be + in the antrum, and since everything looks like antrum, if - you are in the body.

Front 18

granulomatous gastritis causes (<1% of gastritis)

1.
2.
3.

Back 18

1. Gastric Crohn's

2. Sarcoid (10% of systemic patients), in antrum

3. Isolated granulomatous gastritis (idiopathic)

Front 19

Patient with dyspepsia, iron deficiency, and diarrhea.

Gross: normal stomach

Micro: marked intraepithelial lymphocytosis, and in LP (>25/HPF)

IHC: CD3, CD8+

1. Assc. with what (2) conditions

Back 19

Lymphocytic gastritis

1. H/ pylori and Celiac disease

TX for H. pylori resolves it.

Front 20

Immunocompromised patient with gastritis.
A. Viral causes:
1.
2.

B. Bacterial:
1.
2.
3.
4.

C. Fungal
1.
2.
3.
4.

D. Parasites

E: Patient with dibilitation, crepitus in stomach wall

Back 20

Infectious gastritis

A. Viral
1. CMV- typical inclusions- perivascular
2. HSV- assc. with necrosis

B: bacterial
1. TB- caseating granulomas
2. MAI- seen in AIDS. also AFB stain
3. Syphillis- hourglass somach, plasmacytosis. spirochetes seen with WSS
4. Whipple's dz

C: Fungi

1. Histo
2. Apergillis
3. Mucor
4. Candida

D: Parasites
1. Anisakiasis (raw fish)
2. Strongyloides- larvae in gastric pits
3. Schistosomiasis- AIDS
4. Giardia- seen in atrophic gastritis

E: Supprative gastritis- caused by strep, staph, e coli, clostrifium.

Front 21

Patient with weight loss, watery diarrhea, andominal pain, anemia

Gross: antrum and body nodularity and erythema

Micro: superficial mucosa a diffuse or patchy distribution of subepithelial collagen. It traps capillaries and inflammatory cells. LP has increased inflammation.

IHC: trichrome, - for amyloid, - for collagen IV and laminin (normal BM components)

1. Assc. with what other findings?

Back 21

Collagenous gastritis

1. Collagenous colitis, celiac sprue, lymphocytic gastritis, other autoimmune dz

Front 22

Man (3:1) with hypoproteinemia, epigastric pain, edema, dyspepsia. progressive.

Gross: giant polypoid mucosal folds, cribiform and spongy stomach.

Micro: Marked elongation and tortuosity of gastric foveolar hyperplasia in the body. Deep glands have cystic dilitations.

IHC: overexpression of TGFa, r/o CMV, H. Pylori.

Back 22

Menetrier's disease

Front 23

Patient with multiple and reccurent gastric ulcers. Hypergatrinemia

Gross: Marked hypertrophy of mucosal folds in stomach, ulcers.

Micro: hypertrophic parietal cells that extend to the foveolar neck and antrum.

IHC: gastrin, Chr, Syn

1. what is the cause?
2. Genetics?

Back 23

Zollinger-Ellison syndrome

1. gatrinomas in the pancreas/SI.
2. 80% sporadic, 20% due to MEN1

Front 24

Patient with abdominal pain, GI bleeding, nausea, vomiting, weight loss.

Gross: broad or sessile polyp on the stomach wall

Micro: hyperplastic, tortuous, gastric foveolae. Papillary infoldings seen. Surface maturation is present. Look for dysplasia

1. MC site?

Back 24

Gastric hyperplastic polyp

Common- 3-6% of all adults, MC gastric polyp in world (not US)

1. antrum

Front 25

middle age woman (2:1) eith asymptomatic gastric lesion

Gross: fundic/body polyposis, 1-7 mm in size

Micro: proliferation of oxynic mucosa with cystically dilated fundic glands lined by parietal cells, chief cells, mucous neck cells.

What is associated with this lesion?

Back 25

Fundic gland polyp

MC gastric polyp in the US

1. FAP patients, PPI use

Front 26

Patient with h/o gastroenterostomy, now with gastric mass near site.

Gross: 1-3 cm polypoid masses around ostomy sites

Micro: foveolar hyperplasia, regenerative changes, and cystically dilated pyloric-type glands that can be either A) superficial or B)deep. Chronic inflammation and fibrosis present

Back 26

Gastritis cystica polyposa
A) gastritis cystica superficialis
B) gastritis cystica profunda

Front 27

60 YO man with bile reflux; dyspepsia, abdominal pain, nausea, vomiting.

Gross; small sessile yellow nodule in the antrum. May be multiple , 1-5 mm

Micro: loose clusters of lipd-laden macrophages (foamy) in the LP. Surrounding stomach may show evidence of chemical gastropathy or gastritis

IHC: Oil red O, sudan black, CD68

Back 27

Gastric xanthomas

Front 28

middle aged patient with incidental stomach mass, or may have obstruction, pain, nausea.

Gross: sessile or polypoid mostly submucosal mass

Micro: expands the base of the mucosa and splays the muscularis mucosa, consists of proliferation of spindle cells with mixed chronic inflammatory infiltrate. May have "onion skin" appearance.

IHC: vimentin, CD34, SMA, Calponin, CD68, Cyclin D1 +

Back 28

Inflammatory fibroid polyp

Front 29

Patient with unexplained blood loss in the GI tract. H/o autoimmune dz, like Raynaud's phenomenon.

Gross: Parallel, red vascular stripes travering the antrum and converging on the pylorus.

Micro: foveolar hyperplasia, dilated mucosal capillaries with fibrin thrombi, fibromuscular hyperplasia. No inflammation. Submucosal vessels are dilated and tortuous.

1. chief DDX?

Back 29

Gastric antral vascular ectasia (watermellon stomach) GAVE

1. A: Portal hypertensive gastropathy- seen with cirrhosis- no thrombi, thickened gastric walls with dilated veins, in the body B: Dieulafoy's lesion- is an ARTERY that is massively dilated and causes massive intermittent bleeding.

Front 30

Patient with gastric polyp in a background of atrophy

Gross: MC in the antrum

Micro: polypoid lesions with predominantly foveolar glands with low-to-high grade dysplasia, as seen in the colon

Back 30

Gastric adenoma

2nd MC gastric polyp in the US (after FGP)

Front 31

Elderly man from asia with a h/o chronic gastritis presents with a stomach mass

Gross: polypoid/fungating mass based on the pylorus/antrum (50-60%).

Micro: well-formed glands that have a range of cytologic atypia that invade into the MP, prominent desmoplastic response, dirty background.

IHC: CK7+, CK20-
CEA, EMA +

1. Incidence?
2. risk factors

Back 31

Gastric adenocarcinoma

1. 2nd MC Ca worldwide

2. Diet rich in nitrites, smoking, salt, smoked food, H. Pylori, EBV, and atrophic gastritis

Front 32

Patient with vague abdominal pain, vomiting, hematemesis, weight loss. May have carcinoid syndrome.

Gross: small polypoid lesion in the stomach

Micro: small round cells in trabeculae or gland-like formations, uniform central nuclei, salt-n-peppa nuclei.

1. 3 types?

Back 32

Neuroendocrine tumors of the stomach (carcinoid)

A:
1. autoimmune atrophic gastritis (65%)
2. MEN-1 or ZE syndrome (ECL cell hypertrophy)(15%)
3.larger, unassociated (20%)

Front 33

Patient with vague abdominal pain, increased bowel movements, weight loss, weakness. H/o autoimmune disorder.

Gross: attenuated duodenal villi

Micro: intraepithelial and LP chronic inflammation and villous atrophy.

1. Incidence?
2. Genetics?
3. Definitive DX?

Back 33

Celiac disease

1. 1%
2. HLA DQ2, DQ8
3. improvement with GFD

Front 34

middle-aged man with diarrhea, weight loss, fever, lymphadenopathy.

Gross: yellowish-white plaques in the distal dudenum/jejunum

Micro: blunted villi with distension of LP by foamy macs. Macs contain PAS+ rods.

Back 34

Whipple's disease

Front 35

Patient with h/o stem cell transplant, with anorexia, nausea, food intolerance. Secretory diarrhea


Gross:
normal appearing mucosa

Micro: Epithelial cell apoptosis in deep crypts, crypt drop-out. May get crypt abscesses, villous blunting in severe cases.

1. when does it occur?
2. Incidence (in this population)?
3. Grading (I-IV)?

Back 35

GVHD

1. 3 weeks after TX

2. 10-40%

3. I- mild apoptosis; II- apoptosis with abscess; III- extensive crypt drop-out; IV- denudation of mucosa

Front 36

Most common cause of protracted diarrhea in early childhood/infancy?

Gene associated?

Back 36

1. Autoimmune enteropathy

2. FOXP3

Front 37

AA man with obstructing abdominal mass, may have jaundice, GI bleeding.

Gross: Small intestine with ampillary exophytic mass or distal "apple core" lesion with circumferential bowel involvement

Micro: cellular pleomorphism, complex gland architecture, luminal necrosis, invasion of LP and bowel wall.

IHC: CK7+/CK20+/-

1. predisposing risk factors?
2. MC location?

Back 37

Adenocarcinoma of the small intestine

1. Smoking, red meat, fats, any condition that causes chronic inflammation

2. Duodenum (preampullary). If Crohn's- Illeum

Front 38

middle aged man with peptic ulcers, elevated gastrin levels. May have history of endocrine malignancies.

Gross: small sumucosal polypoid lesion in the duodenum

Micro: monotonous proliferation of small bland polygonal cells with moderate cytoplasm and round nuclei with salt and pepepr chromatin. May have psammoma bodies.

1. associated with what genetic disorder?

2. What other hormone also secreated, what is the phenomenon called?

3. What percent are functional?

Back 38

Duodenal Carcinoid tumor (gastrinoma)

1. MEN-1

2. Somatostatin- von Ricklenhousen's disease, although not all features seen

3. 1/3

Front 39

Patient with abdominal pain or small bowel obstruction, intussusseption. May also have watery diarrhea, flushing, endocardial fibrosis.

Gross: may be multicentric (30%), large jejunal mass.

Micro: monotonous proliferation of small bland polygonal cells with moderate cytoplasm and round nuclei with salt and pepepr chromatin.

1. what is the cause of the symptoms?

2. what is also often seen with this lesion?

Back 39

Jejunoilial Carcinoid tumor

1. serotonin production by the tumor cannot be broken down by MAO in liver and lungs. This is the most common cause of carcinoid syndrome

2. Metachronous carcinoma elsewhere.

Front 40

Most common metastases to the small bowel?

1.
2.
3.
4.

Back 40

SI- most common site of mets to the bowel

1. Melanoma
2. breast
3. colon
4. lung

Front 41

middle aged person with a abdominal pain, GI bleeding, and a mural mass. Can occur anywhere in the GI tract.

Gross: usually solid/cystic mass with hemorrhage in the muscularis propria

Micro: spindled and epithelioid cells, typically mostly spindled cells that are short, uniform with tapered nuclei and eosinophilic fibrillary cytoplasm. Can be palisading, whorled, or fascicles. Stroma can look myxoid. "Skeoid fibers"

IHC: CKit, DOG1, CD34, actin, S100, PDGFRa

1. Genetics?

2. Syndromes associated?

3. How is it staged?

4. MC location? Mets?

Back 41

GIST

1. C-KIT or PDGFRa mutations (chr 4)

2. Neurofibromatosis1, Carney's triad

3. mitotic count and tumor size (less than 5/50 HPF, <2 cm)

4. Stomach, then SI. MC mets to the liver, peritoneum

Front 42

Incidental mural mass found in screening colonoscopy/endoscopy

Gross: polypoid mass in the submucosa, mucosa, or muscularis propria. Well circumscribed, white surface.

Micro: NON encapsulated lesion with lymphoid cuff c germinal centers, may have intralesional lymphocytes. composed of interlacing bundles of spindle cells that are loosely palisading. Tapered nuclei.

IHC: S100, C34, GFAP, Collagen IV +.
CKIT, p75 -

Back 42

Gastric/GI Schwannoma

Front 43

incidental sessile lesion found on routine colonoscopy. Can be sporadic, or h/o cancer syndrome (when diffuse)

Gross: 1-3 cm sessile polyp in the colon. can be diffuse

Micro: expanded LP by collections of spindled cells within a fibrillary matrix and irregular nests of ganglion cells

1. what are the associated syndromes?

Back 43

Ganglioneuroma

1. MEN2B, NF1, FAP

Front 44

Child with abdominal mass, can be solitary or multinodular (30%).

Gross: white and infiltrative, up to 20 cm

Micro: myxoid and inflamed stroma (mixed) spindled cells that resomble histiocytes (MFH), or sclerotic dosmoid-like areas with calcification.

IHC: SMA, ALK.

Genetics: ALK gene rearrangements

Back 44

Inflammatory myofibroblastic tumor (IMT) of the GI tract

Front 45

Young woman with clinical suspicion of appendicitis- features wax and wane

Gross: cysts on the GI tract filled with brown fluid

Micro: serosal or MP involvement by columnar glands with hemosiderin deposition and a fibroblastic response.

1. MC location?

Back 45

Endometriosis of the GI tract

1. Sigmoid colon, then appendix

Front 46

Common Viral infections of the GI tract:
Virus, feature, and MC site:
1.
2.
3.

Back 46

1. CMV- colitis/cryptitis, ulcers- anywhere

2. HSV- ulceration, sloughed cells- anorectum

3. Adenovirus- surface apoptosis, focal inflammation- colon

Front 47

DDX in patient with chronic diarrhea and BX that shows apoptosis in the colonic crypts

1.
2.
3.
4.

Back 47

1. GVHD
2. chemo/drugs
3. CMV
4. AIDS enterocolopathy

Front 48

Bacterial infections of the GI tract and their key histologic feature

1.
2.
3.
4.

Back 48

1. Yesinia- granulomatous appendicitis
2. Clostridium- volcano lesion/pseudomembrane
3. Mycobacteria- caseating granulomas
4. Spirochetosis- "fringe" of lumenal surface in the colon

Front 49

Parasitic infections of the GI tract
Organism/common site/ feature

1.
2.
3.

Back 49

Parasitic infections of the GI tract

1. Entmoeba histolytica/ Cecum/ 10% of world population. in ulcers- foamy cytoplasm with ingested RBCs

2. Leishmaniasis/ anywere in GI/ sanfly bites; macs with organisms (amastigotes) that have kidney bean nucleus and cillia.

3. Enterobius (pinworms)/ anus/large bowel/ 2-5 mm worms with lateral ala and intestines/uterus visible. Cause granulomas

Front 50

young patient with recurrent episodes of bloody diarrhea.

Gross: diffuse large bowel involvement- erythema, granular mucosa

Micro: Increased LP chronic inflammation and crypt architectural distortion. Can have polys in the colonic crypts during active disease

1. What is the familial association?

Back 50

Ulcerative colitis

1. 25%

Front 51

Young adult patient with intermittent cramping abdominal pain, non-bloody diarrhea, and fever. May mimic appendicitis.

Gross: multifocal process along GI tract that resemble apthous ulcers, cobblestoning. May see "rake" erosions.

Micro: cryptitis/absecesses, adjacent to normal crypts. Lymphoid aggregates, non-caseating granulomas, transmural inflammation.

Back 51

Crohn's disease

Front 52

middle aged WOMAN with chronic watery diarrhea

Gross: normal or linear ulcers

Micro: intact crypt architecture with increased superficial plasma cells and thick subepithelial collagen (2-5x size). Intraepithelial lymphocytes seen.

1. Associated with what drug use?

2. Assc with what other Go condition?

3. What is this called when all features are present EXCEPT the thick collagen band? what drugs are associated?

Back 52

Collagenous colitis

1. NSAIDs
2. celiac disease
3. Lymphocytic colitis- also assc. with celiac disease, ranitidine, sertraline, asprin, PPIs

Front 53

older patient with heart disease or younger patient post surgery or drug use present with abdominal pain and bloody diarrhea.

Gross: rads may show "thumbprinting", geographic areas of ulceration, pseudomembranes, submucosal edema. MC at splenic flexure

Micro: acutely shows superficial mucosal necrosis that spares deeper crypts, crypt drop out.

Back 53

Ischemic colitis

Front 54

Patient with h/o ostomy and abdominal pain with mucous discharge

Gross: erythema and friable mucosa in bypassed colon

Micro: large, nodular lymphoid aggregates with prominent germinal centers. Apthous lesions were mucosa erodes over lymphoid aggregate

Back 54

Diversion colitis

Front 55

1. What feature is characteristic of mucosal prolapse/solitary rectal ulcer syndrome?

2. Who gets this?

Back 55

1. fibromuscular hyperplasia with strands growing vertically along elongated crypts in the LP.

2. young women with dysfunction of the puborectalis muscle= excessive straining

Front 56

1. Most common polyp in the colon?

2. Risk for malignancy?

Back 56

1. Hyperplastic polyp

2. no

Front 57

Colorectal adenocarcinoma

1. Distinguish adenocarcinoma of whites from blacks?

2. Incidence/rank?

3. Associated risk factors?

4. IHC?

Back 57

1. Whites have left sided, blacks right sided CA

2. 3rd MC DXed CA and cause of death in the US (20%).

3. FAP, HNPCC, H/o IBD

4. ck20, CK, CAM5.2, EMA, CEA +.

Front 58

60s YO white woma with perianal/vulvar dermal mass.

Gross: well circumscribed, unencapsulated brown/papillary lesion

Micro:complex papillary pattern of fibrovascular cores within a cystic structure. Papillae lined by double layer luminal layer of cuboidial epithelium with apical snouts, and a myoepithelial layer

Back 58

Hidradenoma papilliferum

Front 59

1. Eponym for sqamous dysplasia of the perianal skin? In the anal canal?

2. Associated risk factors?

3. IHC?

Back 59

1. Bowen's disease; AIN (anal canal intraepithelial dysplasia)

2. HPV 16/18, female, AA, AIDS

3. P16 for HPV

Front 60

MC site for primary melanoma in the GI tract?

Back 60

Anorectum