How Does Radiotherapy Treat Cancer
There are many people with cancer who want to know exactly how does radiotherapy treat cancer? The way this works has often been overly simplified by experts who end up leaving out some key details about this form of treatment. Radiation is a form of energy in waves or particles as they are called which destroys the genes and some molecules of the cells under treatment. Genes are known as the controllers of the cell which tell it how exactly to grow and then later divide. When these cells are exposed to radiation they are damaged so that the cancerous cells cannot grow or probably divide any further. This is how radiation therapy kills cancer cells, as well as shrinks tumors.
How does radiotherapy treat cancer - Life Cycle of Cells
Before you can fully understand how radiotherapy can treat cancer you need to know a bit about the life cycle of a cell. There are 5 phases of growth for a normal healthy cell, one phase out of these five is known as splitting, when the cell splits / divides it becomes two cells which is referred to as mitosis.
The five phases are:
- G0 = Resting phase of a cell
- G1 = Manufacture of RNA and required proteins
- S = Then DNA is formed
- G2 = Getting ready for mitosis
- M = Mitosis i.e. the cell now becomes two cells
How does radiotherapy treat cancer - The affect of radiation?
Knowing the phases of a cell is very important in radiation cancer treatment since radiation will kill the cells to start off with so that the cancerous cells do not replicate. However, this type of treatment does not usually affect cells which are in their resting phase or are in the phase of slowly dividing. The time it takes for a cell to die or be damage will depend upon how fast the cell is growing and the amount and type of radiation which is being used for cancer treatment. Radiosensitivity is a term used to describe how much a cell will be affected or damaged.
How does radiotherapy treat cancer – how cancer cells work?
Cancerous cells are probably the fastest replicating cells and they can often replicate out of control. When radiation therapy is applied the cells which are replicating are stopped yet it also affects other normal surrounding tissue, it is this damage to normal cells which can cause some side effects. Every time radiation therapy is administered there is a balance between killing cancer cells and trying to minimize damage to healthy cells which needs to be maintained.
However, it is important to understand that radiation will not always kill cancerous cells or healthy cells immediately. It can take days, weeks or even months of treatment for the cells to start dying and the process can continue on for many months even after the treatment has ended. Fast growing tissue like that of your skin, bone marrow and the lining of your intestines are probably the ones which will be affected immediately. This is why radiation treatment has long term side effects which may not become visible until many days and months after treatment.