Introduction To Pathology Flashcards
(19 cards)
Define Pathology
‘The study of suffering’
The study of disease and cellular dysfunction.
Why are they called cells and who named them?
Robert Hooke. Examined cork under a microscope and thought they looked like monks cellular so named them cells.
Who is Rudolf Virchow?
The Pope of Medicine, The Father of Modern Pathology
Discredited the four humours theory and observed that all cells are derived from each other.
What is disease?
A pathological condition of a body part, an organ, or a system characterised by an indent field group of signs or symptoms. A disturbance of homeostasis.
What is the importance of a microscopic diagnosis?
Definitive diagnosis. Can be used before surgery to determine the margins that need to be cut, guiding the extent and the type of the surgery.
What is histology?
Study of tissues. Samples are biopsies.
What are the advantages of histology?
Often therapeutic and diagnostic.
Assesses cell architecture and can compare typical cells.
Determines extent of invasion or completeness of excision.
Easier for immunohistochemical and molecular testing.
What are disadvantages of histology?
Very invasive and more expensive than cytology.
What is cytology?
The study of cells away from their tissue.
What are the advantages of cytology?
Faster and cheaper
Non-invasive or minimally invasive and safe.
What are the disadvantages of cytology?
Higher error rates.
Not generally used for diagnosis - just to confirm/ exclude cancer.
What is ascites?
Fluid in the abdomen.
What tissues are serous carcinomas normally derived from?
Ovary Fallopian tube Uterus Cervix Peritoneum
How does a histopathologist arrive at a diagnosis?
Recognition of patterns: Is it normal? Inflammatory or neoplastic? Benign or malignant? Primary or metastasis?
When it is cancer, what can a histopathologist tell us?
Type of cancer Grade (aggressiveness) Stage (spread) Completeness of excision Efficacy of further treatments
How is cancer staged?
WHO TNM system
T = if the tumour has invaded other tissue
N = are local or distant lymph nodes involved?
M = are there metastases? - confirmed by radiologist
What percentage of breast tumours express ER and Her2?
ER positive - 80%
Her2 positive -20%
Expression determines which therapy is used.
What are cytokeratins?
Family of intracellular fibrous proteins that are present in almost all epithelia. 20 are known and expression is tissue specific so can be used to determine primary site of carcinoma.
Example: CK7+/CK20- = lung, breast, endometrium, ovary, thyroid
CK7-/CK20+ = large bowel and some gastric carcinomas
What are frozen sections and when are they used?
10 minute process to harden tissue samples quickly by freezing in a cryostat. Not routinely used as morphology is not as clear as traditional methods. Used during surgery to establish presence and nature of a lesion.