Lectures 6 + 7 - Role of the Lab and Biomarkers Flashcards
What is the gold standard for cancer diagnosis?
Histology
Give some examples of different samples that might be taken
Tissue sample - biopsy
Cytology - exfoliative, fine needle aspiration
What sorts of things might the histology report mention?
- Is it malignant?
- What sort of malignancy?
- How malignant - grade
- How far has it spread - stage
- Is it all out - surgical excision margins
What cytological changes might suggest malignancy?
Nuclear pleomorphism
Increased mitotic bodies
Hyperchromia - nuclei stain darker
Increased proliferation
How is breast cancer graded?
Bloom-Richardson/Nottingham grading system:
- Tubule formation - glands
- Pleomorphism
- Mitotic counts
Name some ancilliary techniques
- Immunohistochemistry
- PCR
- In situ hybridisation
Name 3 biological factors that are prognostic indicators
Stage
Grade
Biological markers such as Her2
What is a cancer biomarker?
Substance or process indicative of the presence of cancer in the body
What are the 4 major classes of cancer biomarker?
Genetic
Epigenetic
Proteomic
Glycomic
What are the 3 major uses of biomarkers?
Diagnostic
Predictive
Prognostic
List some features that would make a biomarker ideal
Specific and sensitive Predictive Fast/cheap/easy to analyse Detected in minimally invasive manner Reflects kinetics of disease Reflects progression of disease
Give some examples of genetic biomarkers
Hypermethylation of p16 in oral cancers
Mutations in EGFR
BRCA1/2
Give some examples of diagnostic biomarkers
PSA - Prostate cancer
CA-125 - ovarian cancer
alpha-fetoprotein - liver cancer
What is the difference between prognostic and predictive biomarkers?
Prognostic - identifies likely course of disease in an untreated individual
Predictive - identifies sub-populations of patients who are most likely to respond to a given therapy
What is the difference between a solid and a liquid biopsy?
Solid - tissue sample
Liquid - blood sample
