Neoplasia Flashcards
Tumour vs cancer
Tumour is a group of abnormal cells that form a mass or growth (not always cancer)
Cancer is a disease where abnormal cells uncontrollably divide, often forming a tumour, characterised by remission and relapse
Benign tumour
Noncancerous tumours that are surrounded by a capsule, grow slowly and remain localised (non-invasive), have normal structure
Malignant tumour
Cancerous, have abnormal heterogenous cell and tissue structure, grow rapidly and can metastasise, not enclosed in a capsule
Carcinoma vs adenocarcinoma
Carcinoma: cancer of the epithelium
Adenocarcinoma: specifically from glandular epithelium
Oncogenes
Tumour suppressor genes
Caretaker genes
Autonomy
Anaplasia
Angiogenesis
Oncogenes: promote tumour growth by increasing proliferation
TSG: limit cancer development by inhibiting proliferation (p53)
Caretaker genes: repair damaged DNA
Autonomy: ability of cells to avoid cell controls such as apoptosis
Anaplasia: loss of normal cell functioning
Angiogenesis: formation of new blood vessels, tumour stimulates this to grow and meet metabolic needs
The last 3 are characteristic of metastasis
Role of chronic inflammation in cancer development
- Inflammatory cells release cytokines and growth factors that stimulate cell proliferation and vascular growth (angiogenesis factors)
Role of viral infection in cancer development
+ HPV development
- Chronic infection by viruses such as hepatitis B or C & HPV increases risk of liver & cervical cancer
- HPV virus inserts DNA into cervical cells and produces oncogenes
Carcinogens
Environmental agents that have carcinogenic properties
Environmental factors that increase risk of cancer
- Smoking
- Diet
- Obesity - insulin resistance relates to pathogenesis of cancer due to increased FA circulation from adipose tissue
- Alcohol
- Occupational hazards
- UV
Tumour cell markers
What are they, types, use, issues
- Substances produced by cancer cells that are detectable in the blood, spinal fluid or urine
- Hormones, enzymes, genes, antigen (e.g. prostate specific antigen PSA)
- Used to screen for high risk, diagnose, and follow clinical course
- Problem: also produced by non-cancerous tissues
How cancer is evaluated
- X-ray. CT, MRI
- Biopsy esp sentinel node biopsies
Cancer staging
TNM system
* T: tumour size
* N: involvement of LNs
* M: degree of metastasis
Clinical manifestations of cancer
Symptoms are due to tumour pressing on organs, treatment, and inflammatory cytokines acting on the CNS and PNS
* Pain (obstruction, destruction and inflammation)
* Anaemia (reduced RBC, iron malabsorption and haemorrhaging)
* Fatigue
* Cachexia & anorexia
* Infection, thrombocytopenia & anaemia (cancer & treatment suppresses bone marrow production of RBCs, WBC and platelets)
8
Cancer treatments
Chemotherapy: non-selective cytotoxic drugs that target cell growth and replication
Combination therapy: use of multiple therapies which serve different functions. and to avoid drug resistance
Adjuvant therapy: the use of drugs after initial treatment, such as surgery, when there is minimal cancer remaining but risk of metastasis
Neoadjuvant: early use before surgery/radiation to decrease size
Hormonal: drugs that interact with hormone receptors in hormone-dependent tumours
Immunotherapy: using the immune system to kill cancer and avoid destroying healthy tissue (tumour specific vaccines for melanoma, monoclonal antibodies in non-hodgkins lymphoma)
Radiation: use of ionising radiation to damage cancer cells without damaging normal structures, making them more vulnerable to other treatments
Surgery: complete removal. debulking or palliative
Therapeutic index
Effective dose needed to kill cancer cells compared to the dose that would be harmful to normal cells (usually very low)