Session 3 - Histological interpretation Flashcards
first questions to ask when given a tissue slide
- Have we got the correct specimen with the correct clinical form and detail?
- What type of tissue sample (biopsy, resection)
- Orientation
we are looking at a …….. of a ….. structure in ….
We are looking at a cross section of 3D structure in 2D
the small bowel mucosa- cross section
- Villi- finger like projections
- absorption
- Different views of the same structure
Higher magnification versus lower magnification
- Start at lower power
- Get a better idea of the architecture of the tissue
- E.g. at a close glance this tree looks diseased, however further away it is clear it is a healthy weeping willow
what is this?
e.g. the more magnified version looks malignant, however when we take a step back it is clear that these are just the germinal centres of lymphoid tissue
what tissue is this
lung tissue
- can see alveoli air spaces
- will also see airways and vascular supply
abnormal lung tissue can be due to
inflammation e.g. due to smoking
Neoplastic tissue
inflammation in the lungs e.g. due to smoking
normal architecture of the lung tissue not maintained–> alveoli form large air spaces and form bullae
if bullae burst
pneuothorax/ hard to breathe
neoplastic tissue benign vs malignant
- Benign – mature cells which have happened in the wrong place
- Malignant- lung tumour
benign tumours
- Localised
- No invasion
- No metastases
- Slow growth
- Good differentiation
- Few mitoses
- Normal nuclear chromatin
- Uniform cell size
- Compress tissue
malignant tumour
- Spread
- Invasion
- Metastases
- Rapid growth
- Poor differentiation
- Loads mitoses
- Inc nuclear chromatin
- Pleomorphism
- Invade and destroy tissue
summary of interpreting histology speciment
- is this lung tissue?
- Yes: is it normal?
- No: is it inflammatory or neoplastic
- neoplastic: is it benign or malignant?
- malignant: is it primary or secondary?
eosin
acid- negatively charged attracted to positive molecules such as proteins in the cytoplasm
PINK
Haematoxylin
- basic- positively charged attracted to nucleic acid- negatively charged
PURPLE
difference bertween hisotlogy versus cytology: what is cytology
- individual cells removed via aspirate or exfoliated
histology
looking at cells in natural architecture
e.g. smear test
normal tissue from liver
normal tissue from skeletal muscle
commpon pathology: apoptotic body’s e.g. in the liver
Common pathology: Liquefactive necrosis of glomerulus
common pathology: acute inflammation
neutrophil polymorphs
common pathology: chronic inflammation
lymphocytes
