1 - Introduction Flashcards
What is the difference between histology and cytology and what are the advantages and disadvantages of both?
Cytology is looking at disaggregated cells, e.g spinal fluid, rather than tissues that pathology looks at
How do you tell a cell is malignant?
- Hyperchromatinism
- Lots of nucleoli mitotic figures/Mercedes Benz
- Enlarrged nucleus
- Varying nucleus and cell sizing and shapes
What is a serous carcinoma?
Epithelial malignancy from the lining of a cavity that produces a serum-like fluid
What questions does a histopathologist ask when looking at a tissue?
- Is this normal or not?
- Is this inflammatory or neoplastic?
- Is this benign or malignant?
- Is this a primary tumour or metastatic?
What is staging and grading of cancer?
Grading - indication of how quickly it is likely to grow and spread. More normal looking = lower grade
Staging - Size and extent of tumour and whether it has spread or not
What is Mohs surgery?
Precise surgical technique for skin cancer where thin sheets of skin are removed and examined until only cancer-free tissue remains
Summarise the pathway of a tissue sample being made for analysis.
What are some antigenic substances that can be identified with immunohistochemistry?
- Cytokeratins: epithelial differentiation markers
- Contractile actin: smooth muscle cells
- Cadherins: deficient in carcinoma
- Hormone receptors
- Microorganisms
- HER2 receptor: predict response to herceptin treatment
What is molecular pathology?
Study of how disease is caused by alterations in normal cellular molecular biology, e.g FISH
What are some issues with frozen section?
- Lesion of interest not in frozen section
- Poor cell morphology so difficult to interpret
- Cannot store
What is a sample frame of a histology report?
- Clinical history
- Macroscopic
- Microscopic
- Conclusion
What substance in the blood would confirm MI?
Trop I or T
What conditions will a fatty liver be seen in?
- Diabetes Mellitus
- Obesity
- Carbon tetrachloride toxicity
- Alcoholism
What accumulates in hepatocytes in patients who drink excess alcohol?
- Mallory’s hyaline (damaged keratin filaments)
- Fat
How does cirrhosis appear histologically?
Bands of fibrosis surrounding nodules of regenerating hepatocytes
What is an opsonin and give some examples?
A substance that coats foreign materials and makes them easier to phagocytose
An appendicectomy is performed. The appendix is found to be covered in an inflammatory exudate.
Describe briefly how such an exudate forms.
- Tissue injury is followed by the release of vasoactive mediators. Arterioles dilate and capillary hydrostatic pressure increases.
- Inflammatory mediators cause endothelial cells to contract and walls of venules to become leaky. Fluid and plasma proteins pass out into the extravascular space as a result of the increase in capillary hydrostatic pressure and the leaky vessel walls
- As plasma proteins have passed into the extravascular space the interstitial fluid colloid osmotic pressure increases and this holds the fluid in the extravascular space
What are some examples of chemokines?
What diseases can cause granulomas and what cells can be seen in a granuloma?
• Tuberculosis
- Syphilis
- Leprosy
- Cat scratch disease
- Sarcoidosis
- Wegener’s granulomatosis
• Aspergillosis
- Crohn’s
Why do scars appear white, stretched and hairless when they age?
Hairless: damage to hair follicles and they cannot regenerate after damage as it is complex
Stretched: elastin is damaged and cannot be regenerated so scars can stretch
White: melanocytes cannot regenerate and the small blood vessels regress leaving a fibrous scar
with few vessels
What are abdominal adhesions?
- Bands of fibrous tissue between abdominal tissues and organs
What is warfarin used for and why is it not used first in emergencies, which drug is used first?
Heparin used as acts immediately but warfarin takes a few days
What are some risk factors for DVT and why are pregnant people at risk of DVT?
- In pregnancy the blood is hypercoagulable and there is presence of a pelvic mass so puts pressure on veins, decreasing venous flow back up through the legs, causing venous stasis
What cell is required for a histological diagnosis of chronic inflammation?
Epitheliod histiocytes
In DIC what is normally decreased in the blood tests?
- Fibrinogen levels
What is Leriche syndrome?
A form of central artery disease involving the blockage of the abdominal aorta as it transitions into the common iliac arteries
What is an annular tumour and what are some types of exophytic tumours?
- Annular: forms napkin ring lesion, typically causes obstruction. Tumour grows centripetally
- Exophytic: papillary (finger like projections), polypoid (exophytic mass on stalk), sessile (raised but flat)
What is Wegener’s granulomatosis?
Necrotising granulomas form in small and medium blood vessels. Rare but lethal
