Spindle​ ​cells
Cell​ ​types
- Connecive​ ​tissue:​ ​fibroblasts/​ ​fibrocytes
*collagen*
- Bone:​ ​Osteocytes/​ ​osteoblasts
- Cartilage:​ ​Chonodroblasts/​ ​chondrocytes
- Muscle:​ ​Myocytes
Morphology
- Nucleus​:​ ​basophilic,​ ​medium​ ​sized,​ ​ovoid​ ​or
elongate,​ ​well​ ​defined,​ ​pale​ ​to​ ​moderate​ ​density
- Cytoplasm​:​ ​pink​ ​(eosinophilic),​ ​elongated
Behaviour
- Individual​ ​cells,​ ​but​ ​can​ ​form​ ​sheets,​ ​or
structures​ ​such​ ​as​ ​tendons,​ ​muscles,​ ​bone.
- Often​ ​associated​ ​with​ ​extracellular​ ​matrixes
(collagen,​ ​bone,​ ​cartilage)
Round​ ​cells​ ​*immune​ ​cells*
Cell​ ​types
- Lymphocytes
- Plasma​ ​cells,
- Granulocytes
- monocytes/​ ​macrophages
- Mast​ ​cells
Morphology
- Nucleus:​ ​varies​ ​with​ ​cell​ ​type,​ ​basophilic,​ ​well
defined
- Cytoplasm:​ ​round,​ ​other​ ​features​ ​vary​ ​with​ ​cell
type
Behaviour​ ​or​ ​arrangement
- Individual​ ​cells
- Can​ ​lie​ ​against​ ​each​ ​other​ ​but​ ​don’t​ ​form
structures
Steps:
1. Look​ ​at​ ​the​ ​general​ ​structure​ ​(architecture)​ ​with​ ​low​ ​power
- What​ ​is​ ​this​ ​tissue​ ​(given)
- List​ ​the​ ​structural​ ​elements
- Take​ ​note​ ​of​ ​the​ ​arrangement​ ​of​ ​the​ ​elements,​ ​to​ ​see​ ​whether​ ​they​ ​are​ ​all​ ​in​ ​their​ ​normal​ ​place
2. List​ ​and​ ​take​ ​notes​ ​of​ ​constituent​ ​elements​ ​and​ ​non-constituent​ ​elements
Structures
Liver
Stained​ ​in​ ​pink​ ​(connective​ ​tissue)
- Hepatic​ ​lobule​ ​(central​ ​vein​ ​and​ ​portal
triad,​ ​portal​ ​triad​ ​includes​ ​hepatic​ ​portal
vein,​ ​bile​ ​duct​ ​and​ ​hepatic​ ​artery)
- Blood​ ​vessels​ ​(with​ ​RBCs)
Cancer:​ ​Liver​ ​cancer
Microscopy​ ​(normal)
Intestine
-
Skin
-
Epithelial​ ​layer​ ​(simple​ ​columnar
epithelium)
Connective​ ​tissue
Smooth​ ​muscle​ ​tissues
Capillaries​ ​(with​ ​RBCs)
Epidermis
Dermis
Hair​ ​follicles
Blood​ ​vessels
Sweat​ ​gland
Sebaceous​ ​(Exocrine)​ ​glands​ ​→​ ​secrete
oil​ ​or​ ​waxy​ ​matter
Skin​ ​cancer:
Lung
-
Alveolar​ ​sacs
Alveoli​ ​(simple​ ​squamous)
Bronchi
Cancer:​ ​Lung​ ​cancer​ ​(​adenocarcinoma​)
- Hypertrophic​ ​tumor​ ​cells​ ​(increased​ ​in
size)
- The​ ​infiltration​ ​of​ ​various​ ​inflammatory
cells​ ​can​ ​be​ ​prominent​ ​and​ ​occaisional
hisiocytic​ ​multinucleated​ ​giant​ ​cells​ ​can​ ​be
present​ ​in​ ​areas​ ​with​ ​degradation​ ​of
normal​ ​structures.
Muscle
Each​ ​skeletal​ ​muscle​​ ​fiber​ ​is​ ​a​ ​single
cylindrical​ ​muscle​​ ​cell.​ ​An​ ​individual​ ​skeletal
muscle​​ ​may​ ​be​ ​made​ ​up​ ​of​ ​hundreds,​ ​or
even​ ​thousands,​ ​of​ ​muscle​​ ​fibers​ ​bundled
together​ ​and​ ​wrapped​ ​in​ ​a​ ​connective​ ​tissue
covering.​ ​Each​ ​muscle​​ ​is​ ​surrounded​ ​by​ ​a
connective​ ​tissue​ ​sheath​ ​called​ ​the
epimysium.
Cardiac​ ​muscle​​ ​appears​ ​striated​ ​like​ ​the
skeletal​ ​muscle​​ ​due​ ​to​ ​arrangement​ ​of
contractile​ ​proteins.
Cardiac​ ​muscle​ ​fibers​ ​are​ ​long​ ​cylindrical
cells​ ​with​ ​one​ ​or​ ​two​ ​nuclei.​ ​The​ ​nuclei​ ​are
centrally​ ​situated​ ​like​ ​that​ ​of​ ​smooth​ ​muscle
Smooth​ ​muscle​ ​fibers​ ​are​ ​long,
spindle-shaped​ ​(fusiform)​ ​cells.​ ​Note​ ​the
single​ ​and​ ​centrally​ ​placed​ ​nucleus​ ​in​ ​each
smooth​ ​muscle​ ​cell.​ ​The​ ​absence​ ​of​ ​striation
is​ ​also​ ​characteristic​ ​of​ ​the​ ​smooth​ ​muscle
cells
(skeletal)
Lymph
node
Cancer:​ ​Lymphoma
CT
Tumour
cell
Characteristics​ ​of​ ​malignant​ ​neoplasms
include:
● More​ ​rapid​ ​increase​ ​in​ ​size
● Less​ ​differentiation​ ​(or​ ​lack​ ​of
differentiation,​ ​called​ ​anaplasia)
● Tendency​ ​to​ ​invade​ ​surrounding
tissues
● Ability​ ​to​ ​metastasize​ ​to​ ​distant​ ​tissues
Cytologic​ ​features​ ​of​ ​malignant​ ​neoplasms
include:
● Increased​ ​nuclear​ ​size​ ​(with​ ​increased
nuclear/cytoplasmic​ ​ratio--N/C​ ​ratio).
● Variation​ ​in​ ​nuclear​ ​or​ ​cell​ ​size
(pleomorphism).
● Lack​ ​of​ ​differentiation​ ​(anaplasia).
● Increased​ ​nuclear​ ​DNA​ ​content​ ​with
subsequent​ ​dark​ ​staining​ ​on​ ​H​ ​and​ ​E
slides​ ​(hyperchromatism).
● Prominent​ ​nucleoli​ ​or​ ​irregular
chomatin​ ​distribution​ ​within​ ​nuclei.
● Mitoses​ ​(especially​ ​irregular​ ​or​ ​bizarre
mitoses).
Answer​ ​format:
Describe​:​ ​(1-2​ ​short​ ​paragraphs)
1. Architecture​ ​of​ ​the​ ​tissue
- what​ ​type​ ​of​ ​tissue​ ​it​ ​is
- what​ ​types​ ​of​ ​cell​ ​make​ ​up​ ​this​ ​tissue
- spindle,​ ​round,​ ​epithelial​ ​[squamous/​ ​cuboidal/​ ​columnar;​ ​simple/​ ​stratified/​ ​pseudostratified]
- any​ ​CT?​ ​spaces?
- whether​ ​the​ ​cells​ ​are​ ​forming​ ​any​ ​particular​ ​structure​ ​(e.g.​ ​vessels,​ ​tube,​ ​glands)
a. Constituent​ ​elements​ ​of​ ​the​ ​normal​ ​tissue
- Cellular​ ​(parenchyma)​ ​constituents​ ​e.g.​ ​nucleus​ ​and​ ​cytoplasm
- Morphology​ ​:​ ​size,​ ​shape,​ ​colour​ ​[medium​ ​to​ ​high​ ​power]
- Behaviour:​ ​orientation,​ ​location,​ ​grouped/individual​ [​ medium​ ​power]
- Non​ ​cellular​ ​(stroma)​ ​constituents​ ​e.g.​ ​connective​ ​tissue,​ ​bone,​ ​cartilage,​ ​spaces
- Morphology​ ​(how​ ​do​ ​they​ ​look​ ​like):​ ​shape,​ ​colour
- Behaviour:​ ​location,​ ​loose/dense,​ ​regular/irregular,​ ​reticular
b. Non​ ​constituent​ ​elements​​ ​(those​ ​do​ ​not​ ​belong​ ​to​ ​the​ ​normal​ ​tissue)
- Cellular​ ​(parenchyma)​ ​constituents​ ​e.g.​ ​nucleus​ ​and​ ​cytoplasm
- morphology​ ​:​ ​size,​ ​shape,​ ​colour
- Behaviour:​ ​orientation,​ ​location,​ ​grouped/individual
- Non​ ​cellular​ ​(stroma)​ ​constituents​ ​e.g.​ ​connective​ ​tissue,​ ​bone,​ ​cartilage
- Morphology​ ​(how​ ​do​ ​they​ ​look​ ​like):​ ​shape,​ ​colour
- Behaviour:​ ​location,​ ​loose/dense,​ ​regular/irregular,​ ​reticular
Interpretation​ ​(1​ ​simple​ ​paragraph)
-
Explain​ ​the​ ​features​ ​that​ ​lead​ ​to​ ​your​ ​conclusion​ ​(from​ ​the​ ​above​ ​structures​ ​you​ ​described)
-
State​ ​whether​ ​it​ ​is​ ​controlled​ ​or​ u
​ ncontrolled​ ​growth​ ​(if​ ​it’s​ ​uncontrolled,​ ​is​ ​it​ ​benign​ ​or​ ​malignant?)
a. Malignant​:
- Invasive,​ ​Spread-out​ ​(metastasis)​,​ ​(locally​ ​into​ ​“where”,​ ​e.g.​ ​alveolar​ ​spaces/​ ​lymphatic
tissue)
- Pleomorphic​ ​(cell​ ​alteration​ ​→​ ​loss​ ​of​ ​specialisation),​ ​causing​ n
​ ecrosis
- Any​ ​mitotic​ ​figures​?
b. Benign​:​ ​no​ ​pleomorphism​ ​(structure​ ​differentiation​ ​retained),​ ​no​ ​metastasis
-
Give​ ​a​ ​summary​ ​of​ ​the​ ​important​ ​features​ ​of​ ​the​ ​lesion​ ​(state​ ​out​ ​the​ ​features​ ​of​ ​the​ ​lesion;​ ​one​ ​word​ ​each)
1. Severity​ ​→​ ​mild/​ ​marked/​ ​severe
2. Time-course​​ ​→​ ​peracute/​ ​acute/​ ​chronic​ ​→​ ​determined​ ​by​ ​the​ ​exudate​ ​and​ ​type​ ​of​ ​WBCs​ ​present
- Peracute:​ ​transudate​ ​(not​ ​much​ ​protein​ ​contents​ ​but​ ​water​ ​→​ ​not​ ​much​ ​pink​ ​staining)
- Acute:​ ​Usually​ ​haemorrhage​ ​and​ ​oedema​ ​and​ ​neutrophils​ ​are​ ​often​ ​predominant
- Chronic:​ ​Cells​ ​dominate​ ​in​ ​the​ ​exudate,​ ​fluid​ ​is​ ​limited​ ​(cellular​ ​events​ ​>​ ​vascular​ ​events)
3. Distribution​ ​→​ ​focal/​ ​multifocal/​ ​diffuse/​ ​widespread/​ ​portal/​ ​centrilobular/​ ​follicular/​ ​cortical​ ​etc
4. Site​ ​(anatomical​ ​site)
5. Lesion
- Benign:​ ​-​ ​oma
- Malignant:​ ​-​ ​sarcoma​ ​(spindle​ ​cells),​ ​-​ ​carcinoma​ ​(epithelial​ ​cells)
e.g.​ ​lung
- Disorder​ ​of​ ​Growth
- Uncontrolled​ ​(disturbing​ ​archietecture​ ​and​ ​filling​ ​no​ ​function)
- Malignant​:​ ​pleiomorphic,​ ​invasive​ ​(locally​ ​into​ ​alveolar​ ​spaces/​ ​into​ ​lymphatic​ ​vessels)​ ​→​ ​Causing
necrosis​ ​(likely​ ​by​ ​thrombosis)
- Epithelial​ ​cells​:​ ​forming​ ​groups​ ​and​ ​sheets
E.g.​ ​Haemangioma​ ​(benign​ ​growth​ ​at​ ​blood​ ​vessel)
Description
The​ ​section​ ​shows​ ​a​ ​piece​ ​of​ ​skin,​ ​showing​ ​epidermis,​ ​dermis​ ​and​ ​subcutis.​ [​ description​ ​of​ ​architecture]
-
In​ ​the​ ​subcutis​ ​there​ ​is​ ​a​ ​roughly​ ​ovoid,​ ​well​ ​demarcated​ ​mass.
-
The​ ​epidermis​ ​and​ ​dermis​ ​towards​ ​the​ ​edges​ ​of​ ​the​ ​specimen​ ​show​ ​stratum​ ​corneum,​ ​granulosum,
spinosum​ ​and​ ​basal​ ​in​ ​normal​ ​arrangement,​ ​as​ ​well​ ​as​ ​adnexal​ ​structures​ ​such​ ​as​ ​hair​ ​follicles​ ​and​ ​sweat
glands.
-
Towards​ ​the​ ​center​ ​of​ ​the​ ​specimen,​ ​overlying​ ​the​ ​subcutaneous​ ​mass,​ ​the​ ​epidermis​ ​and​ ​dermis​ ​are
thinner,​ ​and​ ​there​ ​is​ ​an​ ​absence​ ​of​ ​adnexal​ ​structures.
-
-
The​ ​subcutaneous​ ​mass​ ​has​ ​a​ ​well​ ​defined​ ​border​ ​and​ ​appears​ ​to​ ​consist​ ​of​ ​a​ ​tightly​ ​packed
collection​ ​of​ ​thin​ ​walled​ ​cavities.
-
These​ ​contain​ ​red​ ​blood​ ​cells,​ ​and/​ ​or​ ​pink​ ​amorphous​ ​material.​ ​[non​ ​constituents]
-
The​ ​cavities​ ​are​​ ​lined​ ​by​ ​a​ ​single​ ​layer​ ​of​ ​cells​ ​with​ ​an​ ​extremely​ ​flattened​ ​nucleus​ ​and
cytoplasm​ ​[non​ ​constituents],​​ ​resembling​ ​the​ ​endothelial​ ​cells​ ​that​ ​line​ ​normal​ ​blood​ ​vessels.
Underlying​ ​this​ ​(between​ ​the​ ​cavity-​ ​like​ ​structures)​ ​is​ ​a​ ​fine​ ​network​ ​of​ ​eosinophilic​ ​fibres​ ​and
occasional​ ​spindle​ ​cells​ ​(connective​ ​tissue).
Overall,​ ​the​ ​mass​ ​resembles​ ​a​ ​proliferation​ ​of​ ​thin-walled​ ​blood​ ​vessels​ ​of​ ​varying​ ​size​ ​but​ ​uniform​ ​in
structure​ ​and​ ​cell​ ​morphology,​ ​containing​ ​red​ ​blood​ ​cells​ ​and​ ​plasma.​​ ​No​ ​mitotic​ ​figures​ ​are​ ​visible.
Interpretation
This​ ​is​ ​a​ ​proliferation​ ​of​ ​vascular​ ​endothelium.
-
It​ ​serves​ ​no​ ​apparent​ ​purpose​ ​and​ ​is​ ​localised​ ​(therefore​ ​unlikely​ ​to​ ​be​ ​a​ ​controlled​ ​proliferation).​ ​There​ ​is​ ​no
evidence​ ​of​ ​pleiomorphism,​ ​high​ ​mitotic​ ​rate​ ​or​ ​invasion,​ ​and​ ​the​ ​cells​ ​are​ ​well​ ​differentiated​ ​and​ ​forming​ ​well
defined​ ​structures.
-
Benign​ ​neoplasm​ ​of​ ​vascular​ ​endothelium-​ ​subcutaneous​ ​haemangioma
E.g.​ ​Kidney​ ​(Malignant)
Description
General​ ​architecture
The​ ​slide​ ​shows​ ​a​ ​section​ ​of​ ​kidney.​ ​It​ ​is​ ​normal​ ​in​ ​general​ ​shape​ ​and​ ​approximately​ ​1/3​ ​of​ ​its​ ​mass
appears​ ​normal​ ​in​ ​structure,​ ​with​ ​renal​ ​pelvis,​ ​renal​ ​medulla​ ​containing​ ​collecting​ ​ducts,​ ​and​ ​the​ ​cortex
containing​ ​glomeruli​ ​and​ ​convoluted​ ​tubules.​ ​The​ ​remaining​ ​2/3​ ​appears​ ​as​ ​widespread,​ ​multifocal​ ​to
coalescing​ ​basophilic​ ​areas.
Constituent​ ​elements
The​ ​convoluted​ ​tubules​ ​appear​ ​normal,​ ​being​ ​lined​ ​with​ ​well​ ​defined,​ ​simple​ ​cuboidal​ ​epithelium​ ​and
being​ ​separated​ ​by​ ​minimal​ ​connective​ ​tissue.​ ​The​ ​glomeruli​ ​appear​ ​well​ ​defined,​ ​consisting​ ​of​ ​a​ ​tuft​ ​of
capilaries​ ​in​ ​an​ ​empty​ ​space​ ​(bowman’s​ ​capsule).​ ​The​ ​collecting​ ​ducts​ ​appear​ ​empty,​ ​and​ ​are​ ​lined​ ​with
a​ ​low​ ​cuboidal​ ​epithelium
Non-constituent​ ​elements
In​ ​the​ ​basophilic​ ​portion​ ​of​ ​the​ ​slide,​ ​there​ ​is​ ​a​ ​dense​ ​infiltrate​ ​of​ ​cells​ ​pushing​ ​between​ ​and​ ​displacing
the​ ​renal​ ​tubules​ ​and​ ​glomeruli.​ ​The​ ​infiltrate​ ​consists​ ​of​ ​a​ ​mixture​ ​of​ ​round​ ​cells.​ ​Some​ ​have​ ​small
dense​ ​round​ ​nuclei​ ​and​ ​scant​ ​cytoplasm​ ​(lymphocytes),​ ​others​ ​have​ ​similar​ ​nuclei​ ​but​ ​with​ ​a​ ​moderate
amount​ ​of​ ​cytoplasm​ ​(plasma​ ​cells),​ ​and​ ​many​ ​have​ ​a​ ​large​ ​ovoid​ ​nucleus​ ​and​ ​a​ ​large​ ​amount​ ​of
cytoplasm​ ​(macrophages).​ ​Scattered​ ​throughout​ ​are​ ​cells​ ​with​ ​multiple​ ​round​ ​nuclei​ ​and​ ​abundant​ ​pink
cytoplasm​ ​(giant​ ​cells).​ ​In​ ​clusters,​ ​multifocally​ ​and​ ​in​ ​some​ ​cases​ ​involving​ ​the​ ​glomerulus,​ ​there​ ​are
groups​ ​of​ ​cells​ ​with​ ​a​ ​dense​ ​multi-lobed​ ​nucleus​ ​and​ ​a​ ​moderate​ ​amount​ ​of​ ​cytoplasm​ ​(neutrophils).
Interpretation
- Widespread​ ​infiltration​ ​of​ ​the​ ​renal​ ​interstitium​ ​(connective​ ​tissue),​ ​also​ ​involving​ ​the​ ​glomeruli,​ ​by​ ​a​ ​mixed
inflammatory​ ​infiltrate​ ​consisting​ ​of​ ​neutrophils,​ ​lymphocytes,​ ​plasma​ ​cells,​ ​and​ ​macrophages​ ​and​ ​giant​ ​cells.
- Severe,​ ​widespread,​ ​chronic,​ ​pyogranulomatous​ ​interstitial​ ​glomerulo-nephritis.​​ ​(or​ ​you​ ​could​ ​just​ ​say
- severe,​ ​widespread,​ ​chronic​ ​active​ ​inflammation​ ​of​ ​the​ ​interstitium​ ​and​ ​glomeruli​ ​of​ ​the​ ​kidney)