OC 1 - intro to benign and malginant disease Flashcards
In adult tissues, what is the size of the cell population determined by?
the rates of cell proliferation, differentiation, and death by apoptosis
When is there tissue homeostasis?
when cell division and cell loss are balanced
What can cell numbers be altered by?
- increased or decreased rates of stem cell input
- by cell death due to apoptosis
- by changes in the rate of proliferation or differentiation
Control of the cell cycle is the key to…
regeneration of a cell population
Control of the cell cycle is controlled by…
chemical factors in the micro-environment of the cell (stimulators and inhibitors)
What can growth result from?
- shortening cell cycle time
- recruiting cells from resting or quiescent population
What does quiescent mean?
In a period or state of inactivity or dormancy
Are terminally differentiated cells capable of replicating?
no (e.g. myocytes)
In the liver/kidney can differentiated cells proliferate?
they are normally quiescent but can proliferate when needed
What is hypertrophy? Is it physiological or pathological?
an increase in cell size
physiological and pathological
e.g. muscle - skeletal, cardiac
What is hyperplasia? Is it physiological or pathological?
an increase in cell number
physiological and pathological
e.g. hormonally sensitive organs - endometrium, breast, thyroid
What is gingival hyperplasia, and what is it’s cause?
enlargement of gingival tissues
hyperplastic responses within epithelium and underlying connective tissue
various causes including certain drugs
What is atrophy? Is it physiological or pathological?
reduction in cell size by loss of cell substance
physiological (thyroglossal duct) and pathological
- ageing, lack of use/stimulation, mechanical, functional
What is hypoplasia? What is it’s cause?
reduced size of an organ that never fully developed to normal size
a developmental defect
What is metaplasia? What is it’s cause?
reversible change in which one adult cell type is replaced by another adult cell type
can be part of an adaptive response to stress
reprogramming of stem cells
What is Barrett’s oesophagus?
metaplasia from squamous epithelium to intestinal type epithelium (in the oesophagus)
What are the different types of disorders of growth?
- hypertrophy
- hyperplasia
- atrophy
- hypoplasia
- metaplasia
- dysplasia
- neoplasia
What disorders of growth are potentially reversible?
all except hypoplasia
What is dysplasia?
“abnormal growth”
What is neoplasia?
“new growth”
What does neoplasia result from?
aberration of the normal mechanisms that control cell number i.e. cell production by cell division, cell loss by apoptosis
What factors are used to classify tumours?
behaviour and histogenesis
What are the behaviour types of tumours?
benign or malignant
What does histogenetic classification of tumours mean?
tumours can be further classified according to the cell type they resemble, i.e. their differentiation
most tumours resemble to some extent the tissue from which they arise
What is prognosis?
prediction of the probable course and outcome of disease
appropriate treatment and estimate survival
What factors are considered when making a cancer prognosis?
- tumour type
- tumour grade (histology)
- tumour stage (histology, clinical)
- radiological
- other parameters (patient, tumour)
What does tumour grading involve?
a histological assessment
how well differentiated the tumour cells are
well differentiated tumours tend to have a better prognosis
What does tumour staging involved?
‘anatomical extent of disease’
clinical, radiological and pathological findings
major determinant or appropriate treatment and prognosis
What are the components of TNM staging?
T - extent of primary tumour (greatest diameter of tumour, structures invaded, depth of invasion)
N - absence or presence and extent of regional lymph node metastasis
M - describes the absence or presence of distant metastasis
What does tumour stage correlate with?
Tumour stage correlates well with outcome in most tumour types
In general, higher stage = poorer prognosis
