Flashcards in MOD S9 - Neoplasia I Deck (40)
The abnormal growth of cells which persists after the initiating stimulus has been removed
What is the difference between benign and malignant neoplasms?
Malignant ones invade and spread to other sites (metastasise) whereas benign remain at the site of origin
Malignant have irregular edges due to infiltrative growth edges but benign have smooth, rounded edges (minimal variation in size and shape)
Malignant have a higher mitotic count and may have abnormal forms
Benign tend to retain their specialisation but malignant can be poorly differentiated
What factors are necessary for a mutation to lead to a neoplasm?
The mutation must:
Cause an alteration in cell growth and behaviour
Be passed on to daughter cells
Not be lethal
Where can neoplasm-causing mutations take place?
Tumour suppressor genes
How will a mutation affect a proto oncogene to cause neoplasia?
If it is mutated so it is permanently activated, it becomes an oncogene
How will a mutation affect a tumour suppressor gene to cause neoplasia?
It is permanently inactivated
What are some key differences between neoplastic and healthy cells?
Self sufficient growth signals
Resistance to anti-growth signals
Induce new blood vessels
Resistance to apoptosis
Invade and produce metastases
How does a neoplastic cell have self-sufficient growth signals?
HER2 gene amplification
How does a neoplastic cell have resistance to anti-growth signals?
CDKN2A gene deletion
How does a neoplastic cell grow indefinitely?
Telomerase gene activation
How does a neoplastic cell induce new blood vessels?
Activation of VEGF expression
How does a neoplastic cell have resistance to apoptosis?
BCL2 gene translocation
How does a neoplastic cell invade and produce metastases?
Through altered E-cadherin expression
Discuss the clonality of neoplasms
They are monoclonal
Aka a cell population descended from one common ancestor (which mutated to escape normal growth control)
Abnormal maturation of cells within a tissue
How can a carcinoma in-situ be distinguished from a malignancy in epithelial tissue?
They share all the features of a neoplasm, but a carcinoma will not have invaded the tissue beneath the basement membrane
How are neoplasms named?
If they are benign or malignant
By tissue type (epithelial, connective, haemopoietic, ect)
What would a benign neoplasm in a stratified squamous epithelium be called?
A squamous papilloma
What would a benign neoplasm in a transitional epithelium be called?
Transitional cell papilloma
What would a benign neoplasm in a glandular epithelium be called?
What would a malignant epithelial neoplasm be called?
Where could a squamous cell carcinoma be found?
Skin, larynx, oesophagus
Where could a transitional cell carcinoma be found?
Where could an adenocarcenoma be found?
Stomach, colon, lung, prostate, breast, pancreas
Where could a basal cell carcinoma be found?
What would be the benign and malignant names for a smooth muscle neoplasm?
What would be the benign and malignant names for a fibrous tissue neoplasm?
What would be the benign and malignant names for a bone neoplasm?
What would be the benign and malignant names for a cartilage neoplasm?