Upper GI Flashcards
Biopsy take from oesophagus.
Dx:
Stains to confirm
Key histo features
DDx:
Dx: candida oesophagitis
Stains: PAS, GMS
Key histo features:
ExpertPath
Neutrophilic inflammatory response most common (NB: variable inflammatory response)
Candida stains with GMS and PAS
C. albicans and Candida tropicalis
- Mixture of budding yeast forms, pseudohyphae, occasional true hyphae
Candida (Torulopsis) glabrata
- Tiny budding yeast forms similar to Histoplasma, no pseudohyphae or hyphae
NB: Hyphae usually angled perpendicular to squamous epithelium.
DDx:
- Aspergillosis
- > septate true hyphae branching at acute angles
- Histoplasmosis
- > Histoplasma are smaller than candida, almost exclusively intracellular, halo effect around histoplasma in tissue
Invasion vs superficial colonization? Look for invasive funi in tissue sections. Presence of just a few yeasts without pseudohyphae is not evidence of infection. Appropriate inflammatory response to organiss.
Dx:
IHC:
Histo features
Dx: candida oesophagitis
IHC: PASD/GMS
Histo features: Densely matted pseudohyphae and budding spores in squamous debris, fibrinopurulent exudate or necrotic debris
Adenoid cystic carcinoma (salivary gland tumour)
gastric biopsy N&V in man with anaemia
Dx?
Key features
Dx: Iron pill gastritis
Mucosal injury in the form of erosion, ulceration and granulation tissue, according to the extent of the injury Acute inflammation in surrounding tissue, inflammatory exudate and reactive epithelial changes Crystalline, metallic, brown-black pigmented material deposition in the superficial mucosa and ulcer bed Iron is refractile but does not polarize
antral polyp
dx
Key features demonstrated
ddx
key genetic mutations
Juvenile polyp
hyperplastic non-dysplastic foveolar epithelium and oedematous stroma. (These polyps are characterised by lamina propria oedema, abundant disorted and dilated and mucin filled glands +/- inflammatory cells).
DDx: inflammatory polyp; other syndromic polyps i.e. Peutz-Jeghers polyps or Cronkhite-Canada syndrome polyp
Germline mutations in SMAD4 and the related gene GMPR1A
Below: SMAD4 loss
gastric polyp
dx
IHC
etiology
Gastric pyloric gland adenoma
Key features:
consist of closely packed pyloric-type glands, lined by cuboidal/low columnar epithelia with foamy, ground-glass cytoplasm;
No apical mucin (c.f foveolar type adenoma); nuclei basally orientated.
High-grade PGAs consistently exhibit disturbed architecture, crowded nuclei, and loss of nuclear polarity. High-grade dysplasia is observed in 40–50% of cases,
.
NB: Adenocarcinoma (even focal) is observed in almost half of all cases, however, submucosal invasion does not exceed 10% .
If high-grade dysplasia is present, this is staged as pTis.
IHC: MUC6 (v +), MUC5AC +
Aetiology: sporadic cases normally occur in context of autoimmune gastritis.
stomach lesion
dx?
IHC?
Molecular
GIST with epithelioid morphology
IHC: C-KIT/DOG1, CD34 (nb epithelioid GISTs less consistently (+) for CD34 than spindle cell GISTs.
This image shows cytoplasmic vacuoles.
gastric lesion
dx
IHC
GIST with spindle cells and perinuclear vacuolisation.
IHC: C-kit/DOG1; CD34 (+ more in spindled cell GIST than epithelioid); consider SDHB or SDHA IHC with multinodular/plexiform growth > a/w lymph node involvement
Image: GISTS composed of cytologically bland spindle cells that may feature distinctive perinuclear vacuolization.
GISTs
subtypes
Sclerosing type (a/w calcs)
Pallisaded-vacuolated subtype
GISTs
SDH-deficient GISTs
describe histology
relevance
associated syndrome
Multinodular/plexiform growth, lymphovascular invasion
LVSP/LN mets; more likely to metastasise and are resistant to imatinib therapy
Carey-Stratakis syndrome
gastric biopsy
Atrophic pattern of gastritis:
Key histo features:
Pitfalls:
Common causes:
multifocal loss of th oeriginal gastric glands +/- metaplsia +/- inflammation
NB: Atrophic pattern as an advanced stage of damage is often accompanied by metaplastic pattern. Metaplastic and atrophic pattenrs often coexist as a mixed pattenro f atrophic metaplastic gastritis.
Pitfalls: mistaking of transitional zones of the gastric mucosa (antrum and body, fundus and cardia) that may show a reduciton of expectednormal components as atrophy).
Common causes (2): AIG and HPG
1. autoimmune gastritis: oxyntic gland atrophy + antral sparing
2. HPG shows antrophyloric gland atrophy (oftne a/w IM)
Therefore, antral predominant gastritis is consistent with Hpylori associated chronic atrophic gastritis whiel antral sparing gastritis is typical fo AIG.
stomach, intestinal metaplasia
Endoscopic findings:
Types:
Endo: multiple white plaques
Type 1: metaplastic glands phenotypically resemble those of the small intestine, with eosinophilic absorptive neterocytes with a brush border, alternating with mucus-producing goblet cells and Paneth cells. “Complete IM” or “small intestinal type metaplasia”. When advanced may show villiform architecture.
Type 2: Incomplete IM shows irregular goblet cells interspersed within the gastric epithelium and lacks the brush border, absorptive cells, and paneth cells and resembles colonic mucosa, called “colonic metaplasia”. in type 2 IM, the presence of sulfomucins within the non-goblet cells is beieved to be a/w an icnreased risk of progressio to gastric cancer.
Immunohistochemical markers for subtyping intestinal metaplasia
Complete (type 1) IM vs Incompete (type 2)
Complete (type 1) IM: shows expression of MUC2 in goblet cells, (intestinal mucin) as well as luminal CD10 expression highlighing the presence of enterocytes and decreased expression of “gastric” mucins (MUC5AC and MUC6)
Incomplete IM shows “gastric” mucins (MUC5AC and MU6) coexpressed with “intestinal” mucins MUC2 and lacks CD10 representing an aberrant differentiation.
IM occurs frequently in a/w Paneth cells. The presence of paneth cells should prompt vigilant search for goblet cells.
Mucins by IHC
positive cells:
MUC2
MUC5AC
MUC6
MU1
MUC2: Goblet cells (“intestinal”)
MUC5AC: Foveolar epithelium (cytoplasmic)
MUC6: Pyloric glands (cytoplasmic)
MUC1: not expressed in non-neoplastic stomach.
IHC used to confirm pseudopyloric metaplasia from trual antral mucosa
Gastrin. confirms presence of G cells which are not seen in PPM.