Neoplasia 2 Flashcards
Nucleus moulding meaning
Cells start to stick together and nuclei start to mould
-reflection of rapid growth/overcrowding- cells squashed together
-occurs in very malignant tumours
Coarse chromatin meaning
Chromatin starts looking like old rope
Macronucleoli meaning
Multiple massive nuclei inside cell
Angular nucleoli meaning
Nucleoli starts to overcrowd, becomes very prominent and angular
Anisonucleoliosis
Variably sized nuclei within one cell
Neoplastic cells often have a ________ nucleus with a __________ nucleolus. With _______ & __________ numbers of mitosis figures
Larger
Prominent
Increased & abnormal
Histological features of malignancy; a summary
Enlarged nucleus with prominent nucleolus
Increased mitosis
Multiple nucleoli
Large nuclei
If function of cell is maintained when tumour is present, is this a sign of malignant or benign neoplasia?
Benign; when function altered it is a sign of malignant
True or false, tumour function is often marked species variation
True
Granulosa cell tumour;
Ovarian tumour
-common in what animal
-produces what steroids
-malignant or benign
Common in large animals
Produces oestrogen, androgens & +/- inhibin
Non malignant
Granulosa cell tumour in the mare;
In the mare, depending on what hormone it produces, a different effect will be produced on the animal. What effect will production of
A) Testosterone
B) Inhibin
C) Oestrogen
A) Stallion-like behaviour
B) Anoestrus
C) Nymphomania
Granulosa cell tumour malignant or benign in;
1. Cow
2. Mare
3. Bitch
- Benign
- Benign
- Can be both
Granulosa cell tumour- bitch
Often oestrogen producing- prolonged oestrus
Can be progesterone producing which if prolonged can lead to CEH which then leads to pyometra
Name the Tumour components
Parenchyma- neoplastic cells
-determine biological behaviour
Stroma- non-neoplastic, supporting tissue
-CT
-blood vessels
-host derived inflammatory cells
Essential for tumour growth and provide physical support and nutrients
Interaction between the stroma and parenchyma is a…
2 way process- both can influence one another
Which type of molecules modulate growth rate, differentiation state and behaviour of the tumour cells
Growth factors, cytokines, hormones & inflammatory mediators
What is scirrhous/desmoplastic response
Describe the steps in forming this
Dense collagenous stroma
Forms from neoplastic epithelial cells (parenchyma) producing platelet derived growth factor (PDGF). This triggers activation of tumour associated fibroblast which start producing the collagen; scirrhous.
Describe the Tumour stromal interaction
Tumour production (produces proteases, growth factors, inflammatory mediators) leads to stromal response (produces inflammatory cells, extracellular matrix, vascular endothelium, stroma fibroblasts etc) which leads to tumour response (differentiation rate, proliferation rate, local invasive nests and metastatic capacity).
How does canine disease renal carcinoma & modular dermatofibrosis (GSD) arise?
Inactivation of tumour suppressor gene- heritable change in germ line sequence in all cells
What does epigenetic change mean
Reversible, heritable changes in gene expression that occur without mutation
What is heritable alterations in cancer?
PROGRESSIVE ACCUMULATION OF GENETIC AND EPIGENETIC ABNORMALITIES IN CELLS
Initial heritable alterations in cancer are due to either;
Inherited germ line mutation
Or somatic mutations
What is carcinoma
Type of cancer e.g u can get nasal carcinoma, skin carcinoma etc
What are the 3 steps of tumour development?
- Initiation
- ProMotion
- Transformation & progression
Initiation step of tumour development
Irreversible genetic change introduced into cells/tissue
Initiated cells are Morphologically normal and could remain quiescent for years until an initiator comes along and acts on them
What is an initiator/promoter
Chemical or physical carcinogen (substance capable of causing cancer)
E.g DNA lesions, mutation fixation
Promotion step of tumour development
Outgrowth of initiated cells in response to selected stimuli
Promoters alter gene expression
Initiated cells have growth advantages over uninitiated cells
Not mutation so reversible
Transformation & progression tumour development step
Involves genetic and epigenetic changes
Tumour becomes Increasingly malignant
Which steps of tumour development are reversible and which irreversible
Which steps of tumour development are genetic and which nongenetic
Step 1 irreversible and genetic
Step 2 reversible and non genetic
Step 3 can be both and can be both
What occurs after transformation and progression step of tumour development?
Tumour cells proliferate and sub-clones of tumour cell can occur
Which have slightly different features
Stepwise development of squamous cell carcinoma
Step 1: thickening of epidermis (epidermal hyperplasia)—>leads to benign papilloma
-no sign of invasion
Step 2 : carcinoma beginning to invade into deeper tissues
Step 3: invasive carcinoma appears
