Neoplasia 1 Flashcards
What is neoplasia?
- New growth of tissue resulting in an abnormal mass.
- Growth is also uncoordinated and exceeds the normal rate.
- Growth continues even after stimuli removed
What are the 2 CLINICAL classifications of tumours? (also features of each)
Benign;
- Localised (doesnt spread from site)
- Slower growth rate
- Resembles tissue of origin
Malignant;
- Metastatic (can spread to secondary tumours)
- Faster growth rate
- Pleomorphic (Sizes of cells are variable to environment)
What are the 2 HISTOGENIC (origin of tissue) classifications of tumours?
Epithelial;
- Benign ends in -oma
- Malignant ends in -carcinoma
Connective Tissue;
- Benign ends in -oma
- Malignant ends in -sarcoma
What is carcinogenesis and what are factors which induce it
Formation of tumour/cancer
Environmental (carcinogens) & Genetic
What are examples of CHEMICAL carcinogens?
- Asbestos
- Drugs, diet, alcohol
- Cigarettes/Smoking
How does chemical carcinogenesis take place?
2 Stages
1) Initiation - permanent DNA damage (mutation)
2) Promotion - the agent promotes proliferation
What are examples of PHYSICAL carcinogens?
- Ionising radiation; damages DNA causing mutations, radioactive metals/gases
- UV light; damages DNA, skin cancer - sunbeds
What are examples of VIRAL carcinogens?
- DNA Viruses; more common, viral DNA inserted into host DNA
- RNA viruses; reverse transcribed and then inserted
Examples: Hepatitis B/C, Human Papillomavirus (HPV)
Examples of aetiology (causes) of oral cancer?
Multifactorial;
- Tobacco
- Alcohol
- Diet/Nutrition
- Oral hygiene
- Viruses - HPV…
- Immunodeficiency
- GORD - Gastro-oesophageal reflux disease
What is leucoplakia?
A white patch that cannot be rubbed off or attributed to any other cause - potentially malignant lesion. Can be found in ORAL cavity
How can dysplasia be identified histologically?
Identified by changes in cells’
- appearance
- arrangement
Cellular atypia - IRREGULAR PATTERNS
