Histopathology Flashcards
Histopathologist Report
- Patient Details
- (Working) Diagnosis
- Gross description of specimen
- Microscopic description of specimen
- Final working diagnosis
- Signature
Congo Red?
Amyloid stains red
- Amyloidosis
- CAA
- Alzheimers
Masson’s Trichrome
Collagen stains blue
Helps visualize fibrosis
Luxol fast blue
Stains myelin
Dx of Demyelinating disorders (MS, PML,
Neuromyelitis Optica, ADEM)
Grocott Silver Stain?
Fungi
Pneumocytis jirovecii
Ziehl Neelsen (Acid fast)?
TB
(also stained by
Auramine stain)
India Ink
Cryptococcus
Coagulative (most solid organs) necrosis?
Gross: Triangle-shaped “wedge infarct”
Micro: Loss of nuclei (anucleated cells), Eosinophilic (red)
Liquefactive (Abscess/Brain infarction) necrosis?
Gross: Liquid, creamy (pus) consistency to lesion
Micro: Increased space, accumulation of debris,
Accumulation of neutrophils, macrophages
Fat necrosis (Pancreas/Breast)?
Gross: White deposits (Lipids precipitate out Ca2+)
Micro: Necrotic, anuclear adipocytes
Fibrinoid Necrosis (Vasculitis)
Histological Triad of vasculitis:
- Inflammatory infiltrate
- Thrombotic vascular occlusion
- Fibrinoid necrosis -> Deposition of fibrin in vessel walls
Caseous Necrosis (TB)?
Gross: Cheese-like lesion
Micro: Caseating Granuloma (see later slides)
Apoptosis
Acute Inflammation
chronic inflammation:
Granulomas
Cellular features of dysplasia
- Hyperchromasia
- Increased Nuclear :Cytoplasmic ratio
- Mitotic features
- Cellular pleomorphism
Tissue features of malignancy
- Invasion through basement membrane
- Distortion of tissue architecture
- Invasion into surrounding tissues
- Metastasis
TTF-1 IHC - indicates?
Lung cancer
CK7/CK20 IHC - indicates?
COLORECTAL cancer
cytokeratin IHC - indicates?
Tumours of epithelial origin
Synaptophysin IHC - indicates?
Neuroendocrine tumour
chromogranin IHC - indicates?
Neuroendocrine tumour
CD99 IHC - indicates?
Ewings sarcoma
TdT IHC - indicates?
Blast cells -> ALL/AML
Ki-67 IHC - indicates?
Proliferation index - cancer
Pneumonia - histology?
- Actue inflammatory cells and RBC filling alveolar spaces uniformly
- Congested capillaries in the alveolar septa
Pneumonia - lung
Bronchiectasis - pathology?
- Neutrophillic exudate in bronchi
- Widened bronchi into periphery
Abscess
Walled-off pus-filled cavity
TB
Micro: Caseating Granuloma
* Caseous necrosis in centre
* Macrophages/Giant cells around centre
* Lymphocytes in periphery
Pan-acinar Emphysema
A1AT deficiency
Asthma - histology?
- Thickened basement membrane
- Smooth muscle hypertrophy
- Mucous plugging
- Goblet cell hyperplasia
- Eosinophilia
Adenocarcinoma?
- Back-to-back glands
- Mucin rich
Squamous Cell Carcinoma
SCC
* Keratin pearls
* Intercellular bridges
Small cell carcinoma
(Synaptophysin +ve)
Adenocarcinoma - lung
Squamous Cell Carcinoma - lung
Large Cell Carcinoma - lung
Oesophagus: (Pre-)malignant process?
Eosinophilic oesophagitis
- Eosinophilic micro-abscesses in proximal oesophagus
Eosinophil
Signet ring cells - Stomach cancer
Trophozoites in lumen - Giardiasis
Whipples disease - Periodic Acid Schiff +ve
macrophages (deep pink)
Appendicitis
- Fibrosis/ haemorrhage
- Widespread inflammatory infiltrate
- Erosion/ destruction of mucosa
Ulcerative Colitis - histology?
Continuous inflammation
Microscopic Appearance
* Partial thickness change
* Crypt abscesses, Goblet cell depletion
Crohn’s Disease histology?
Skip lesions
Microscopic appearance
* Full thicknessinflammation
* Granulomas/Inflammatory cell infiltrate
UC
Chrons
Pseudomembranous Colitis
Erosion of
mucosal surface
“Volcano sign”
= Pseudomembrane
(inflammatory cells +
fibrin)
Colorectal Cancer
Liver – Acute inflammation
Liver – Cirrhosis
Bridging
fibrosis
Regenerative
nodules
Primary Biliary Cholangitis
Primary Sclerosing Cholangitis
Onion skin fibrosis
Autoimmune Hepatitis
Stains Iron
Haemochromatosis?
Perls Prussian Blue
A1AT deficiency - stain?
Periodic Acid Schiff
Stains Copper
Wilson’s Disease
Rhodamine Stain
“Ground glass” hepatocytes -> HBsAg
MI infarct at 7 days
- Angiogenesis
- Fibrosis
- Fibroblasts
- Macrophages
Acute infarct @48h
Necrosis of myocardium
* Loss of nuclei
* Hypereosinophilic
Acute inflammatory infiltrate
MI
Contraction bands
(associated with reperfusion)
MI - “Wavy” fibres
Hypertrophic Obstructive Cardiomyopathy (HOCM)
Disorganised fibres
HSV Inclusion Bodies
Encephalitis
Herpes encephalitis
- Bilateral temporal
lobe involvement
Alzheimers
Atrophic Gyri, widened sulci
(relative sparing of occipital lobe)
Alzheimers
Amyloid (plaques/angiopathy)
Alzheimers
Hirano bodies
Phosphorylated tau
-> Neurofibrillary tangles NOT specific for AD!
Alzheimer’s Disease
Granulovacuolar Degeneration (Lysosomes)
Alzheimer’s Disease
Granulovacuolar Degeneration (Lysosomes)
Neuritic Placques
ALZHEIMERS
Frontotemporal Dementia
Atrophy of frontal and temporal lobes
Pick Bodies (composed of tau)
H&E ON LEFT IHC for tau ON RIGHT
Frontotemporal Dementia
Loss of neurons/pigmentation in the
substantia nigra of the midbrain
Parkinson’s
Lewy Body Dementia
Pigmented neuron of
Substantia nigra NEXT TO Lewy Body
IHC: Alpha-synuclein
Lewy Body Dementia
Huntington’s Disease
Loss of the striatum (esp. caudate and putamen)
-> Enlargement of ventricles
Huntington’s Disease
Psammoma body
* Serous ovarian cystadenocarcinoma
* Papillary Thyroid Cancer
GBM
Giant cells
Oligodendoglioma
- Fried egg appearance
- 1p19q co-deletion
Biphasic Antoni A/B pattern
Associated with Neurofibromatosis Type II (bilateral Schwannomas)
Pilocystic astrocytoma
Associated with Neurofibromatosis Type I
Homer Wright Rosettes
- neurobalstoma
- Medulloblastoma
- Pineoblastoma
Flexner-Wintersteiner rosette
- Retinoblastoma
- Medulloepithelioma
Perivascular pseudo rosette
- Epidemyoma
- Central neurocytoma
- Glioblastoma
Lobular Carcinoma in situ
No Lump, Often Bilateral
Loose, blue cells
Ductal Carcinoma in situ
Lump, Unilateral
Ductal carcinoma
Lump, Unilateral
Classical Adenocarcinoma features
Lobar carcinoma
No lump, often bilateral
Loss of E-Cadherin
Tumour cells intersperse within tissue
Medullary Breast Cancer
Renal tumour
Nephroblastoma/Wilm’s Tumour
Triphasic Tumour
Large hyperchromatic nuclei
= Anablastic nephroblastoma (bad)
Adrenal tumour
Neuroblastoma (Synaptophysin +ve, MYC amplification)
Renal Clear Cell Carcionma - kidney
Transitional Cell Carcinoma - bladder
Adenocarcinoma prostate
- Nuclear enlargement of cuboidal cells
- Loss of basal cells
- Classical cellular features of malignancy (N:C ratio, hyperchromasia)
- Classical tissue features of adenocarcinoma: Back-to-back glands
Testicular cancer Subtypes associated with key tumour markers
– Seminomas: Secrete PALP
– Embryonal: Secrete beta-hCG
– Yolk Sac Tumour: Secrete AFP
– Choriocarcinoma: Secete beta-hCG
– Sex cell tumours:
■ Testosterone (Child: Premature puberty)
■ Oestrogen (Child: Delayed puberty, Adult: Gynaecomastia, ED)