Using high energy X-Rays, electron beams and radioactive isotopes to destroy cancer cells and reduce size of tumors, radiotherapy is one of the oldest and most-effective anti-cancer treatments. Radiation treatment damages the genetic materials of cells at the radiated area and thus, division and proliferation of these cells are hindered. Radiation affects the cancer cells through ionization. This effect emerges in two ways; since certain cells are directly influenced by radiotherapy, they die quickly, while damage occurs in chromosome and DNA of others and therefore, they cannot divide, resulting in cell death. Although radiation treatment causes damage in healthy cells along with cancer cells, healthy tissues mostly recover and gain normal functions back.
Recently, technological advancements lead to substantial development in radiotherapy and it is among most successful treatments regarding both treatment outcomes and reduction of side effects. A successful treatment is characterized by ability to deliver the appropriate and efficient radiation dose to the tumor, while the dose exposed by surrounding healthy tissues is minimized. Although it was difficult or even impossible to achieve this goal with antecedent conventional methods, novel techniques ensure the best possible radiation. Three dimensional conformal radiotherapy (3DCRT) is the most common one among these methods. The treatment plan made with a new computer software by adding the dimension of depth to two dimensions (width, length) that are used in conventional methods is called three dimensional treatment plan.
At planning and treatment phases, the tumor volume and healthy tissue volumes in the treatment area are real time evaluated and thus, dose insufficiencies are avoided. The target volume is irradiated by using multiple fields in the treatment. Thus, local control of the disease is booster and the survival may also be influenced, as the tumor tissue can be delivered higher doses. In addition, the side effects on healthy tissue are minimized and quality of life is increased.
Intensity modulated radiation therapy (IMRT) is an advanced form of three dimensional conformal radiotherapy (3D-CRT). Thousands of radiation beams can be guided to different treatment volumes by an advanced computer software and thus, the dose of radiation can be adjusted for treatment volumes. Accordingly, the possible highest dose is delivered to the tumor tissue, while the damage to healthy tissue is minimized. Three dimensional computerized tomography images are used to plan the treatment. The tumor volume that will be irradiated and the healthy tissues that should be protected against high-dose radiation are determined. Comparing to conventional techniques, planning and treatment phases of IMRT take slightly longer, but it is preferred for certain cancers due to high tumor control and reduced side effects.
Recently, IMRT is also used to treat prostate cancer, head and neck cancers, breast cancer and thyroid and lung cancers as well as gynecological cancers, liver cancer, brain tumors, lymphoma and sarcomas. IMRT is also very effective in treatment of pediatric tumors.
All devices at our department are interconnected through a network and they can, therefore, exchange data. Thus, the potential manual errors that may arise during the treatment are minimized. We are also able to exchange images with the PET/CT scanner available at our hospital and thus, the diseased body part can be identified more precisely and accurately.
Linear accelerator: linear accelerator device that generates high-energy X-ray and has state-of-the-art features s used for radiotherapy patients. Varian DMX Linear Accelerator device that is equipped in our clinic help treatments with photon energies of 6 and 15 MV and electron energies of 6, 9, 12 and 15 MeV. Multi-leaf and asymmetric collimators maximize tissue protection, while it is possible to deliver maximum dose to the tumor tissue. Thanks to electronic portal imaging feature of the device, treatment volumes can be on line monitored and they can be checked visually during treatment.
RADIATION THERAPY FOR BRAIN TUMOR
Features of Gamma Radiosurgery: It may eliminate the requirement of open surgery in many brain tumors. The side effects of the procedure are very scarce.
• General anesthesia is not required.
• Most patients are discharged to home in the treatment day.
• There is no recovery period.
• No wound develops in scalp and head.
• Scalp hair is not cut.
• Maximum benefit is obtained in return for minimal discomfort.
• Minimal radiation dose is delivered to healthy brain tissue.
