Week 3

Question 1

define tumour, malignancy, and metastasis

Answer 1

tumour- abnormal mass of tissue (benign/malignant)

malignancy- potentially fatal

metastasis- cancer cells spread from mother site to new site through lymphatic system/bloodstream

Question 2

what are the risk factors for the development of mutation and tumourgenesis?

Answer 2

inherited mutation

aging
- autophagy is the self-eating of damaged organelles in cells
- as we age this ability is reduced, damaged mitochondria are not removed
- mitochondria produces more free radicals

environmental
- UV radiation
- chemicals

lifestyle factors
- smoking, alcohol, diet

chronic infections/inflammation

hormone imbalances/weak immune system

Question 3

what are the 3 main routes of metastasis and the common sites?

Answer 3

bloodstream
lymph nodes
direct seeding (through body cavities)

common sites- lungs, liver, bones

Question 4

what is a carcinoma and why are they common?

Answer 4

cancer that originates in the epithelial tissue, common as they are exposed to external stress and continuously divide

Question 5

define dysplasia, neoplasia, metaplasia, and hyperplasia

Answer 5

dysplasia- abnormal cell growth (precancerous but not yet malignant and is reversible), usually in fast dividing cells, classed mild, moderate, severe

neoplasia- uncontrolled, abnormal new cell growth even if stimulus is removed, that form a tumour

metaplasia- cell changes type from changes in environment (lung tissue thickens for protection from smoke)

hyperplasia- elevated division due to stimulation (cells produce more mucus in lungs)

Question 6

what are the differences between benign and malignant tumours?

Answer 6

benign
- never metastasises
- well differentiated (looks like mother cell)
- encapsulated (surrounds normal cells)

malignant
- can metastasise
- can be well-differentiated or undifferentiated (cells can evolve)
- invasive growth (mixed with normal tissue)

Question 7

what does the prefix tell us in nomenclature?

Answer 7

what type of cell originated (leiomy- muscle, chondro- cartilage, osteo- bone, haemangi- epithelial lining of blood vessels)

Question 8

what are sarcomas?

Answer 8

cancers in connective tissue

Question 8

what are side effects of treatment?

Answer 8

healthy cells lost, mutation in healthy cells, scars, radiation burns

Question 9

what are some essential conditions for malignant transformation?

Answer 9

• evasion of ptosis
• self-sufficiency in growth signals (divide without signal)
• insensitivity to growth-inhibitory signals (division despite surrounding epithelial tissues)
• defects in DNA repair (no DNA check process, more mutations)
• limitless replication (divide regardless of telomere length)