Oncology Flashcards
(35 cards)
How can viruses promote cancer?
Some express oncogenes that induce malignancy on infection
What is an oncogene?
When activated forms tumour, regulation lost by mutation
What is a photo-oncogene?
Regulate proliferation, differentiation and apoptosis
Mutations promote unregulation so can become an oncogene
What are tumour suppressor genes?
Rb, P53 - produce proteins that prevent proliferation
When both gene copies are mutated ➡️ loss of function
How many mutations does it take to progress to a tumour?
10-12
What are the six ways mutations on cells result in tumour?
Sustained proliferative signalling Evading growth suppressors Resisting cell death Enabling replicative immortality Inducing angiogenesis Activation of invasion and metastasis
What are the characteristics of sustained proliferative signalling? (3)
Uncontrolled secretion of endogenous GF
GF receptor mutation - over expression or activation without ligand
Intracellular signalling - mutation of proto onc Ras/Raf ➡️ MAPK path
What is the characteristic of evading growth suppressors?
Rb and P53 regulate cell cycle ➡️ mutation ➡️ proliferation
What are the characteristics of resisting cell death? (2)
Extrinsic pathway - process signals
Intrinsic - sensing, integrating signals ➡️ caspase cascade ➡️ apoptosis
- mutation ➡️ imbalance ➡️ resist apoptosis, ⬇️ regulate death rec
What are the characteristics of enabling replicative immortality? (2)
Normal cells replicate definite number of times - telomeres
Malignant cells up regulate telomerase adding segments
What is the characteristic of inducing angiogenesis?
Secrete angiogenic factors VEGF to stimulate new blood vessels
What are the characteristics of activating invasion and metastasis? (4)
Local invasion - lymph node, blood vessels ➡️ tissues ➡️ lesion
Tumour cells produce enzymes to to disrupt tissue
Adhesion molecules produced to attach to other cells and ECM
Lose E-cadherin to allow detachment and metastasis
How do we grade tumours?
Low
Intermediate
High
What is TNM?
Tumour - 123
Node - 01
Metastasis - 01
How do we stage lymphoma according the the WHO?
I - V
Sub-stage a without systemic signs
b with systemic signs
What is paraneoplastic syndrome?
Tumour effects distant through hormones, enzymes, cytokines
What are the baseline tests for in oncology? (4)
Haematology
Biochemistry
Urinalysis
Coagulation parameters
Name some paraneoplastic effects? (11)
Hypercalcaemia Hypoglycaemia Hyperviscosity Gastric ulceration Vomiting Endocrine - adreno, thyroid Pyrexia IMD Hypertrophic osteopathy Dermatological Cancer cachexia
How does chemotherapy work?
Cytotoxic drugs that interfere with cell growth, division
When is chemo a primary treatment? (5)
Lymphoma Myeloma Leukemia Disseminated MCT Disseminated histiocytic sarcoma
When is adjuvant therapy used?
After surgery for highly metastatic tumours
Osteosarcoma, haemangiosarcoma, high grade soft tissue tumours, grade 3 MCT
What does neo-adjuvant chemo do?
Shrinks tumours prior to surgery
What routes of administration are there for chemotherapy? (5)
IV SC PO Intracavitary Intralesional
What does the cell kill hypothesis state?
Drug kills percentage of cells, never complete removal
