3- Cancer Flashcards
Describe a neoplasm
abnormal mass of tissue, the growth of which is virtually autonomous and exceeds that of normal tissues. The growth is uncoordinated and persists after the cessation of the stimuli that initiated the change”
Gives examples of glandular neoplasms
Adenoma
–Cystadenoma
–Papilloma
–Polyp
Give examples of stromal neoplasms
Fibroma –Lipoma –Angioma –Leiomyoma –Osteoma/chondroma
Compare benign and malignant tumours
B:Well’ differentiated
●Usually slow growing
●Rarely invade locally-cohesive, expansile, encapsulated mass
●Seldom metastasize
M: Anaplasia - complete lack of differentiation
- Rapid turnover- ‘chemo targets’
- ‘Infiltrative’ margins, locally
- Metastasize (except 2 tumours!!)
What are 4 mechanisms of metastasis?
Lymphatic e.g. breast cancers
●Haematogenous
●Body cavities (transilomic)
●Contiguous (continuous spreading )
Describe carcinogenisis
Multistep process
●Malignancy acquired in a step wise fashion - ‘tumour progression’
●Accumulation of successive mutations
Give some carcinogen examples
Chemicals ●Viruses ●Ionising/non-ionising radiation ●Hormones ●Bacteria, fungi, parasites ●Miscellaneous
What are the 4 classes of regulatory gene?
Growth-promoting genes - Proto-oncogenes
b. Growth-inhibiting (tumour suppressor) - Anti-oncogenes
c. Genes regulating programmed cell death – Pro-apoptotic genes
d. Genes preventing mutations in the normal cell cycle - DNA repair genes
What are the 2 basic components of tumours?
Parenchyma - the cancer cells that have been transformed
Stroma - tissue around the cancer cells which consists of connective tissue, blood vessels, macrophages, lymphocytes - it’s a supportive system for the cancer cells
What is the suffix of benign tumours, and malignant tumours for parenchyma and stroma?
Suffix ‘oma’, carcinoma, sarcoma
Describe relationship between age and cancer
In general, higher incidence > 55 years
●Certain cancers specifically affect the young e.g leukaemias, neuroblastoma, Wilm’s tumour, retinoblastoma, primary bone sarcomas
Describe relationship between geography and cancer
Stomach cancer higher in Japan compared to the USA
• Colon cancer much less in Japan
• Melanoma much more common in NZ and Australia compared to Scandinavia
• Hepatocellular Carcinoma more common in Uganda - due to aflatoxin
Oesophageal cancer more common in China due to nitrates in soil
.
Describe relationship between environment and cancer
UV light
●Occupational agents like asbestos, naphthyl amine and vinyl chloride, alcohol (liver cancers), smoking (lung, bladder cancer) and
●Infections notably viruses (HPV, HBV, EBV etc)
What are the 3 forms of hereditary cancer
Autosomal Dominant
Inherited cancer syndromes - single mutant gene responsible e.g. retinoblastoma, FAP
●Autosomal Recessive
Inherited defective DNA repair mechanisms e.g. Xeroderma
●Unknown
Familial cancer syndromes e.g BRCA
Give some. Examples of carcinogens
hydrocarbons, amines, nitrosamines, azo dyes, alkylating agents
Give examples of oncogenic viruses
EBV (BL) and HPV (CC), HBV & HCV hepatic cancers
What are oncogenes and give some examples
Classic example is Rb gene (13q) in genetically inherited retinoblastoma (40%)
●P53 (house-keeper of genome)
●BRCA-1 & BRCA-2 breast cancers are familial and one of these mutations present in 80% of breast cancers
What are the 3 factors in cancer stage
“Size of the primary lesion
Spread to regional lymph nodes
Presence of metastases
”
Name 4 components of a successful screening programme
oReliable prediction of tumourbehaviour
oTreatment available
oTarget population has enough people at risk to justify expense
oCost-effective and reliable screening tool
Describe the cervical screening programme
11th commonest cancer in UK
–Most common cancer in females <35 years
–Know disease starts as cervical dysplasia (CIN)
–Detectable with relatively easy, low cost process
–All females between 25-64 eligible
–70% reduction in death’s over 30 year programme
How are cancers diagnosed
Tumour markers and blood serology used to test for the presence of cancer
• Biopsy or Fine Needle Aspiration (FNA) is used to extract a bit of tissue or fluid
to test to confirm the presence of cancer
• To see if the cancer has metastasised imagine will be used:
CT MRI PET
What are some clinical effects of tumours
Benign and malignant tumours both affect the host
• Anxiety about lumps and bumps
• Related to location - pressure, ulceration, infection, bleeding etc.
• Metabolic Cancer Cachexia mediated by TNF
Increased Basal Metabolic Rate (BMR) Reduced Fat
Reduced Muscle Bulk
• Paraneoplastic Syndromes
Endocrinopathies
Hypercalcaemia
Thrombotic Diathesis
Acanthosis Nigricans (brown/black, velvety hyperpigmentation of the skin - usually found in folds of the neck, groin, naval and forehead)
