Introduction to Benign and Malignant Disease Flashcards
What is the size of the cell population determined by?
- Rates of cell proliferation
- differentiation
- death by apoptosis
What is an example of a terminally differentiated cell (not capable of replication)?
Monocytes
What is Apoptosis?
Apoptosis- Programmed cell death
What are Disorders of growth and Neoplasia (uncontrolled growth of cells)?
- Hypertrophy
- Hyperplasia
- Atrophy
- Hypoplasia
- Metaplasia
- Dysplasia
- Neoplasia
What is Hypertrophy?
Hypertrophy - An increase in cell size
What is Hyperplasia?
Hyperplasia - An increase in cell number
- Enlargement of gingival tissues
- Hyperplastic responses within epithelium and underlying connective tissue
- various causes including drugs
What is Atrophy?
Atrophy - Reduction in cell size by loss of cell substance
Causes e.g. ageing, lack of use/stimulation
What is Hypoplasia?
Hypoplasia - Reduced size of an organ that never fully developed to normal size
A developmental defect
What is Metaplasia?
Metaplasia - 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
E.g. Bronchus
What is the only growth change that is not reversible?
Hypoplasia
What does Dysplasia mean?
Abnormal growth
Is a broad term and can be used to describe different types of abnormal growth such as Epithelial dysplasia,
What are the different degrees of dysplasia?
Mild
Moderate
Severe (carcunoma in situ)
The more severe forms have a more significant risk of progressing to invasive malignancy
What is Neoplasia?
A neoplasm is an abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues, and persists in the same excessive manner after cessation of the stimuli that evoked the change
i.e. uncontrolled growth of cells that is not under physiologic control
Why do tumour cells clone expand?
Tumour cells lack the normal control mechanisms thus the clone expands due to uncontrolled proliferation
What are the 2 classifications of tumours?
- Behaviour
- Histogenesis
What the 2 types of behaviour?
- Benign
- Malignant
What are Benign Tumours
Growth pattern - Expand and remain localised. Well circumscribed. Encapsulated.
Growth Rate - Slower
Clinical Effects - Local pressure effects; hormone secretions
Treatment - Local excision
Nuclei - Small, regular, uniform
Mitoses - Few, normal
What are Malignant Tumours?
Growth pattern - Infiltrate locally, metastasize (spread to different sites)
Growth Rate - Faster
Clinical effects - local pressure and destruction, Inappropriate hormone secretion, Distant metastases
Treatment - Excision +/- additional therapy
Nuclei - Larger, pleomorphic
Mitoses - Increased, often numerous, abnormal forms
Histogenetic Classification of Tumours means what?
Tumours can be further classified according to the cell type they resemble, ie their differentiation.
Most tumours resemble to some extent the tissue from which they arise.
If the Tissue origin is Covering epithelia or Grandular epithelia what are the names of the benign and malignant equivilant?
Covering epithelia
- Benign - Papilloma*
- Malignant - Carcinoma*
Glandular epithelia
- Benign - Adenoma*
- Malignant - Adenocarcinoma*
What will affect Cancer Prognosis?
- Tumour type
- Tumour grade
- Tumour stage
- Patient
Why is it important to know the tumour type?
Every tumour behaves differently.
Anatomical knowledge is also important such as lymphatic drainage
What are the tumour grades?
- Well differentiated
- Moderatelt differentiated
- Poorly differentiated
