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Using the IGRT and IMRT methods to treat prostate gland carcinoma and their side effects
KŘIVSKÁ, Klára
Prostatic carcinoma is a disease with a continuously increasing number of newly diagnosed cases all over the world. According to the commonly available statistic data it is the most frequent tumour disease of men. As far as oncological causes of death are concerned, it occupies the second place, after lung cancer. The situation in the Czech Republic corresponds to this trend. The incidence in this country has almost tripled in the last two decades. On the other hand, the number of deaths due to prostatic carcinoma decreases and it is approximately one third lower now. This very significant difference is given especially by the possibility of examination for the prostate-specific antigen (PSA) within the framework of preventive medical check-ups at general practitioners or at other specialists. The modern treatment of prostatic carcinoma, whether it concerns radical (curative) treatment or support (palliative) treatment, also has had an indisputable positive effect. According to the data obtained from the statistics managed by the National Cancer Registry from 2009, the number of newly diagnosed prostatic carcinomas in the Czech Republic reached 119.3 cases per 100,000 men. The death rate was 28.5 cases per 100,000 men. In conversion to absolute numbers from 2009 it means that 6154 men were diagnosed with a prostatic carcinoma and 1472 men died of it. Great success of modern treatment is confirmed also by a percentage expression of survival of patients after the end of treatment. In the time period of the last thirty years, the overall five-year survival for men with a prostatic carcinoma has increased from 68% to the current almost 100%. This means that an overwhelming majority of patients still live after five years from the diagnosis of their disease. Treatment of prostatic carcinoma has included the conform radiotherapy since the time of its introduction. The pioneers of this therapy are Japanese scientists Umegaki and Takahashi, who invented, in the 1960s, the first rotational conform radiation technology. It is more often associated with introduction of computer tomography (CT) into ordinary clinical practice. It was only in 1983 when a 3D planning system was presented, which then facilitated further development of tumour-conform radiotherapy. It was established that the doses from conventional techniques (e.g. a box) are not sufficient for the patients, do not lead to recovery and, quite on the contrary, they even increase the risk and major development of side effects. The advanced method of intensity-modulated radiation therapy (IMRT), which started to be applied in practice in the 1990s, achieved much better results. Besides a change in the beam shape it enables a change in the beam intensity as well. This can be achieved in cooperation with a multi-leaf collimator (MLC) which changes the shape of its lamellas dynamically and thus it modifies and transfers its beam. Method IMRT better and more accurately shaped beam and thereby more saving to surrounding healthy tissue
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