Cancer is disease characterized by the growth of abnormal cells. Any treatment strategy will therefore be aimed at interfering with the growth of these cells because they tend to affect the normal functioning of other useful body cells. Similarly, radiation interferes with the existence of the abnormal cells. The crux of the mechanism used by radiation therapy is to interfere with the gene structure of the cancer cells, and in the process inhibit their ability to reproduce and/or interfere with the functioning of other body cells.
Objectives of radiotherapy can be summarized as destruction of localized tumors, reinforcement of chemotherapy or surgical treatments and reduction of the cancer cells before one undergoes surgery. Within radiotherapy, X-ray fall within the class known as external beam therapy. In external beam therapy, a beam (or beams) of X-rays are directed from outside the patient’s body and move through the skin on to the targeted body part. A patient undergoing this kind of therapy is more likely to be exposed to a larger quantity of X-rays because of the rays are applied from outside the body and are thus less target sensitive.
3-dimensional conformal radiation therapy (3D-CRT) and Intensity-modulated radiation therapy (IMRT) are examples of external beam therapy. It the commonly used method where a patient is placed under an X-ray emitting machine and with the help of trained personnel the machine aims a stream of X-rays on to targeted areas of a patient’s body. An alternative to this method is known as internal beam therapy, which works by having radioactive material being placed or implanted in the tumorous cells.
Benefits of using X-rays The high proportion of patients undergoing X-ray radiation therapy is a pointer to the possible benefits of using the therapy. According to (Koreaittimes, 2007), 50% of patients suffering from cancer worldwide are undergoing radiotherapy, and in that percentage; radiotherapy X-rays are still the most popular. To understand the advantages and disadvantages of X-ray therapy, it would be helpful to look at it in comparison with other available therapies, lest the comparison becomes hollow.
The table below provides a summary of the characteristics of related to different particles used in radiotherapy from which the advantages and disadvantages of each can be deduced. X-rays use electrons, meaning that its characteristics can be deduced by looking at the attributes of electrons. The first advantage deducible is on costs. X-rays have over the years proven to be the cheapest option within radiotherapy, and this has made them the most popular option for hospitals and other treatment facilities. It worth noting that radiotherapy as a whole is popular with medical practitioners for a variety of reasons.
Prominent among these is the fact that radiotherapy does not carry the risks associated with surgery, while at the same time it does have more efficiency than chemotherapy because it acts directly on the tumor. However, there is a glaring disadvantage of the method as evidenced by the element of dose distribution. Dose distribution refers to how the therapy appropriately positions itself to fight the cancer. The major problem associated with X-rays is their poor targeting that leads to a risk of them damaging the normal cells in their path or neighborhood.
Technology is one other dimension that has made X-rays popular. Their use of electrons has meant that X-rays can be produced by mechanisms that do not require a lot of energy. Subsequently, linear accelerators have proven to be the most appropriate in their production. Today, linear accelerator technology is the most popular in the radiotherapy market because of the relative developments in the technology. Before analyzing linear technology, it is helpful first to understand how and why they are popular in the production of X-rays.
Firstly, electrons, due to their sizes do not require a lot of energy to be accelerated. That fact has made it easy for linear accelerators to be used. Linear accelerators achieve acceleration via a series of suitably positioned electrodes that propel the particles every time they come in to contact with the electric fields associated with the electrodes. For instance, if a linear accelerator has four electrodes arranged in series then the electrons will be accelerated four times because they are propelled every time they pass by the positively charged electrode.