ABSTRACT
The body is maintained in a state of health by the many adjustments which homeostatic mechanisms in the body make every second. Failure of any of these systems can lead to disease processes. This failure may take a number of simple forms. It may be a failure of a control system or an inability to respond to an insult such as an infection, or the response itself may be adequate but may turn against the host instead of the cause of the original imbalance. Broadly, the processes which give rise to problems can be listed as: neoplasia; degeneration; inflammation; and congenital and inherited diseases.
Neoplasia means new growth. It is an area of tissue whose normal growth regulation has been affected, resulting in uncontrolled growth independent of its parent tissue. The word ‘tumour’ simply means a lump, although it is often used synonymously with neoplasia.
