PNP WK4 Flashcards
Neoplasms and cancer
What are neoplastic cells?
- A defective set of genes in a cell that replicate uncontrolled and will eventually form lumps/tumours
- Cells become extra invasive (cancerous) and break off from original tumour and spreads throughout body (matastasis)
What are the steps of mitosis (cell division)?
-Prophase: DNA organizes into chromosomes
-Metaphase: Chromosomes align
-Anaphase: Chromosomes separate
-Telophase: nuclear membranes appear around chromosome sets
-Cytokinesis: Cell is created
-Interphase: G1, S and G2 stages
What are the characteristics of a benign tumour?
Similar to local cells, relatively slow, remains localised
What are the characteristics of a malignant tumour?
Irregular shape, size, not like local tissue, fast growing, invades nearby tissue, fatal
What are the stages of carcinogenesis?
1) Protooncogene becomes mutated, tells cell cycle gene to produce DNA
2) Mutation in inhibitory gene, doesn’t stop constant replication
3) DNA regulator/fixer is switched off and cannot fix DNA
4) Mutated apoptosis gene so cell cannot die to save body
5) Telemerase mutated so telemeres (end of chromosomes) are protected so cell can replicate
6) Growth factors go to blood vessels and give cancer cells to nutrients
7) Cell is different to neighbouring cells and metastasizes
8) NOT RECONGISED AS ISSUE BY IMMUNE SYSTEM
What are the features of bowel cancer?
Tumour grows along side of colon wall and causes bowel obstructions
What are the features of lung cancer?
Are divided into small cell and non-small cell cancers
Carcinomas of the lung occur as a result of abnormal cells in the bronchi, bronchioles and/or alveoli
What are the features of skin cancer?
Divided into non-melanoma (basal cell carcinoma and squamous cell carcinoma) and melanoma
Mutation of the basal stem cell or melanocytes
What are the basic mechanisms of tumour spread?
Invading: tumour’s ability to grow into adjacent tissue, destroys local cells and invades other structures
Metastasis: spreads to distant sites by blood or lymph, broken local tissue erodes into blood/lymph nodes to find suitable environment to continue replicating
Seeding: spread of tumour cells in body cavity fluid and membranes
What are the stages of cancer?
Stage 1: confined to origin tissue
Stage 2: locally invasive
Stage 3: spreads to regional structures (lymphs)
Stage 4: metastasizes to different sites
What are the lab tests used for cancer?
Blood tests, Tumour markers, Genetic testing, CT MRI PET-scan X-Ray, Biopsy
What is the action of chemotherapeutic agent ?
Affects cancer cells and normal cells systemically
Split into cell cycle phase-specific (cells in particular stage of cycle) and cell cycle phase non-specific
What is localised chemo?
- Radiotherapy targets 1 specific location
- Surgery
What is cytotoxic chemo?
- is toxic to both diseased and healthy cells
E.G: antimetabolities (targets cells during S-phase) METHOTREXATE
E.G: antitumour antibiotics (target G2 phase) BLEOMYCIN
E.G: Vinca alkaloids, plant based (target M phase)
E.G: Alkylating agents, non-specific CISPLATIN
What is a Fibroadenoma?
Growth of stroma or epi. cells in breast originating from the lobule, resemble normal cells and are no larger than 2cm