Gastrointestinal Flashcards
Active, chronic colitis with of multiple poorly formed nonnecrotizing granulomas.
Crohn’s disease
Differential diagnosis:
Infectious colitis (e.g salmonella/campylobacter, TB, yersinia)
Plan:
Correlate with clinical history, radiology, and endoscopic findings (e.g distribution of disease ?known Crohn’s ?immunosupressed ?infection ruled out clinically / microbiologically)
Correlate with any concurrent microbiological investigations (e.g. PCR, stool culture)
Special stains: Gram, PAS and GMS, ZN (to evaluate for any infectious agents)
Stomach polyp with elongated, architecturally distorted, irregular foveolae and edematous lamina propria with lymphocytes, plasma cells and eosinophils
Hyperplastic polyp
Plan
Correlate with clinical history and endoscopic impression (?solitary polyp in antrum ?chronic gastritis)
Examine deeper levels (for any areas of dysplasia)
Advice to clinician: frequently assiociated with chronic gastritis (e.g. H pylori, autoimmune gastritis). Sampling of adjacent mucosa is recommended.
Gastric polyp with cystically dilated glands (e.g. lined by chief cells, parietal cells and mucinous foveolar cells). Apocrine snouting of parietal cells may be seen.
Fundic gland polyp
Plan
Correlate with clinical history and endoscopic impression (?FAP ?PPI therapy)
Advice to clinician: may be associated with PPI use, or FAP, where multiple polyps can occur. Clinical correlation is required.
Flask shaped (undermining) colon ulceration with amoebic trophozoites within the ulcer bed and submucosa. The trophozoites have abundant dense bubbly cytoplasm and small round nucleus with peripheral rim of condensed chromatin and central dot-like karyosome.
Amoebic colitis
Plan:
Correlate with clinical history, radiology, and endoscopic findings (?travel to endemic area)
Correlate with any concurrent microbiology investigations - send fresh tissue urgently if not already performed
Special stains: PAS (highlight trophozoites)
Advice to clinician (urgent via phone): This patient has amoebic colitis and may require urgent antimicrobial treatment. This disease may also be reportable (public health implications)
Active colitis with injury and sloughing of superficial colonic mucosa with layer of fibrinopurulent debris (pseudomembrane)
Pseudomembranous colitis
Differential diagnosis:
Ischaemic colitis
Other forms of infectious colitis
Plan:
Correlate with clinical history, radiology, endoscopic findings (?recent antibiotic use ?C diff PCR ?CT angiogram)
Correlate with any concurrent microbiology investigations - send fresh tissue urgently if not already performed
Advice to clinician (urgent via phone): This patient may require urgent antimicrobial treatment and infection control precautions
Deposit on peritoneal surface of resembling appendiceal mucinous neoplasm
Peritoneal mucinous neoplasia (consistent with pseudomyxoma peritoneii)
Plan:
Correlate with clinical history and radiographic features (?history of appendiceal mucinous tumour ?mucinous ascites)
IPX to support Dx: CK20, CDX2, SATB2
Next steps: Discuss at MDT
Inflammation of appendix including neutrophils
Acute appendicitis
Differential diagnosis: Dual pathology (e.g. with endometriosis, NET)
Plan:
Correlate with clinical history and radiographic features (?abdo pain, raised inflammatory markers, CT scan)
Examine further blocks
Otherwise, no further action required for this benign diagnosis
Appendiceal tumour with ‘organoid’ architecture (includes nests, trabeculae, rosettes, follicules/pseudoglands, etc) of neuroendocrine cells - these can be polygonal (epithelioid) or spindled and have round to oval nuclei with finely granular ‘salt and pepper’ chromatin and inconspicuous nucleoli, and eosinophilic cytoplasm.
Appendiceal carcinoid / well differentiated neuroendocrine tumour
Plan:
Correlate with clinical history and radiologic features
Examine further blocks (e.g. for total size, relation to margins, areas of increased mitotic activity etc)
IPX to support Dx: Synaptophysin, chromogranin. Also Ki67 for grading.
Next steps: Formal grade (based on mitotic count and Ki67), synoptic report, discuss at MDT
Colon with empty cystic spaces lined by foreign body giant cells.
Pneumatosis cystoides intestinalis
Plan:
Correlate with clinical history and radiographic findings
Examine further blocks
Advice to clinician: This is a non-neoplastic pathology
Stomach body with lymphoplasmacytic infiltrate in lamina propria, atrophy of oxyntic glands, intestinal/pyloric metaplasia (gastric body may resemble antrum), neuroendocrine cell hyperplasia
Autoimmune atrophic gastritis
Differential diagnosis:
H. pylori gastritis
Antral biopsy (wrong biopsy site)
Plan:
Correlate with clinical history and endoscopic features (?H pylori testing ?autoantibodies)
IPX to support Dx: Synaptophysin and chromogranin (highlight ECL hyperplasia)
IPX to discount DDx: Gastrin (positive would indicate antral biopsy), H. pylori
Anal squamous and colonic mucosa with dilated and congested submucosal veins
Haemorrhoid
Differential diagnosis:
Haemorrhoid with assiociated squamous intraepithelial neoplasia
Prolapse type polyp (inflammatory cloacogenic polyp / solitary rectal ulcer syndrome)
Plan:
Correlate with clinical history and endoscopic findings
Examine further blocks (ideally entire lesion) for any areas of squamous dysplasia
Otherwise, no specific action is required for this benign diagnosis
Small bowel polyp with arborizing smooth muscle cores dividing lobular compartments of mucosa
Peutz-Jegher polyp
Plan:
Correlate with clinical history and endoscopic findings (?known/suspected Peutz-Jegher syndrome)
Examine further blocks (ideally entire lesion) for any areas of dysplasia
Advice to clinician: May be assiociated with familial syndrome. Clinical correlation is required.
Colon polyp with hyperplastic surface and disorganised bundles of smooth muscle splaying between crypts. Often has congested blood vessels and haemorrhage
Mucosal prolapse type polyp
Plan
Correlate with clinical history and endoscopic impression (?distal colon ?diverticular disease)
No specific action required for this benign diagnosis
Well circumscribed, submucosal spindle cell lesion in GIT. Elongated bland nuclei and may have paranuclear vacuoles. Cells have eosinophilic cytoplasm, indistinct cell borders and form short fasicles/palisades.
Gastrointestinal stromal tumour (spindle cell type)
Differential diagnosis:
Schwannoma
Leiomyoma
Plan:
Correlate with clinical history and radiology
Examine further blocks (e.g. for total size, relation to margins, areas of differing morphology / increased mitotic rate)
IPX to support Dx: CD34, cKIT, DOG1 (expect positive)
IPX to discount DDx: S100, SMA and desmin
Next steps: Risk stratification, synoptic report, discuss at MDT
Well circumscribed nodule in submucosa of stomach composed of bland spindled cells with prominent eosinophils.
Inflammatory fibroid polyp
Differential diagnosis:
Gastrointestinal stromal tumour
Schwannoma
Plan:
Correlate with clinical history and radiology
IPX to support Dx: CD34
IPX to discount DDx: S100, cKIT, DOG1
Glands resembling endometrium with surrounding stroma, haemorrhage/haemosiderin pigment
Endometriosis
Plan:
Correlate with clinical history and radiology
Examine further blocks
IPX to support Dx: CD10, ER, PR
No specific action required for this benign diagnosis
Small intestine with trophozoites resembling fallen leaves between villi. May show villous blunting, increased intraepithelial lymphocytes, and increased inflammatory cells and prominent lymphoid aggregates in lamina propria
Giardiasis
Villous colorectal polyp with serrated architecture, lined by goblet cells and tall columnar cells with abundant eosinophilic cytoplasm and pencillate, hyperchromatic nuclei (low grade dysplasia)
Traditional serrated adenoma
Plan:
Correlate with clinical history and endoscopic findings
IPX to support Dx: Not required (MUC2, MUC5AC)
Small bowel lamina propria expanded by abundant foamy macrophages
Whipple’s disease (Tropheryma whipplei infection)
Differential diagnosis:
Other infectious agents (e.g. mycobacterium avium complex, histoplasma)
Plan:
Correlate with clinical history and endoscopic findings (?immunsupression)
Correlate with any concurrent microbiology investigations
Special stains to support Dx: PAS/DPAS
Special stains to discount DDx: AFB, GMS (stain MAC and histoplasma respectively)
Advice to clinician: This is a rare infectious disease. Patient may require antibiotic treatment
Infiltration of the appendiceal wall by tubules, nests, and clusters of cells with prominent intracytoplasmic mucin vacuoles resembling goblet cells, often admixed with variable numbers of Paneth cells and neuroendocrine cells.
Goblet cell adenocarcinoma of appendix
Plan:
Correlate with clinical history and radiology
Examine further blocks - entirely submit appendix (e.g. for depth of invasion/stage, high grade features, relation to margins, LVI/PNI)
IPX: Not required for diagnosis
Next steps: Synoptic report, discuss at MDT
Tubular of tubulovillous adenoma with mucosal prolapse type changes and misplaced glands below the muscularis mucosae, but with only low grade dysplasia, and assiociated lamina propria, in well circumscribed islands.
Tubular/tubulovillous adenoma with pseudoinvasion
Plan:
Correlate with clinical history and endoscopic impression
Examine further blocks - entire polyp (to search for any high grade dysplasia or true invasion)
Small bowel mucosa with markedly reduced plasma cells within lamina propria
Common variable immune deficiency
