Curative radiation therapy can be performed in two different ways: external radiotherapy and brachytherapy. With the radiation produced by modern external radiotherapy devices from high electrical energy outside the patient, the areas to be treated in the body are determined and done externally. While performing these treatments, conformal radiotherapy (3D RT), intensity modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), respiratory-assisted RT (4D RT), Stereotaxic radiotherapy (SBRT) can be performed by using different features of the device depending on the software. While all these techniques aim to give the highest dose to destroy the tumor, they have been developed to take the least dose in the normal tissues around the tumor.
Brachytherapy, on the other hand, is a different form of radiation therapy used in the treatment of cancer. It consists of placing radioactive sources directly or through catheters into or near the tumor to be treated. Radioactive sources are applied to organs with spaces in the body by means of various applicators, and the form is called intraluminal brachytherapy, while the method made through the catheters placed directly on the tumor is called interstitial brachytherapy. Since the effect distance of the radioactive source is limited in these irradiations, the target tumor in the organ in which it is placed receives the highest dose, while the surrounding healthy tissues are least affected by the radiation.
In interstitial brachytherapy, various catheters are placed in the area to be treated, often without the need for a device, and radioactive sources are placed in these catheters, and tumor tissues are irradiated directly.
Devices used in intraluminal brachytherapy; Unlike external radiotherapy devices, they do not produce radiation themselves, and these devices are used by externally loading various radioisotopes with certain properties in terms of half-life and energy.
Iridium-192, cobalt-60, cesium-137, iodine-125 and palladium-103 are among the most commonly used radioisotopes in both types of brachytherapy.
In terms of the energies of the radioisotopes, low dose rate (LDR) or high dose rate (HDR) irradiation is done. Since the radioisotope irradiates at a dose rate of 0.4-2 Gy/hour in LDR brachytherapy, the duration of treatment is longer in this treatment compared to HDR, and irradiation is performed in a single session. In HDR brachytherapy, the treatment takes a short time thanks to the dose rate of the radioisotope over 12 Gy/hour. In these, treatment is often carried out in several fractions.
brachytherapy; Depending on the stage of the disease, it can be performed as an additional option or as the only option in various cancers such as gynecological tumors, breast cancer, prostate cancer, head and neck cancers, skin cancers, lung cancers, esophageal cancer, anal cancer and soft tissue sarcomas.
The GAMMAMED PLUS device we have in our center is a brachytherapy device that performs HDR treatment using iridium-192 radioactive source. Due to the available applicators, brachytherapy is performed in cervical cancer and endometrial cancer in our center. Depending on the stage of the gynecological tumor, it can be performed after external radiotherapy after surgery or as the only treatment option without external radiotherapy. In addition, it can be used in combination with external radiotherapy or as the only treatment option in patients who do not undergo surgery depending on the stage of the tumor.
In patients with indicated gynecological tumors, appropriate applicators are applied to the patient and 3D treatment plans are made in the computerized planning system with the CT images taken. While administering the appropriate tumor dose, radioactive sources are loaded on the applicators attached to the patients in accordance with the plan made in such a way that the dose to be received by the surrounding healthy tissues (bladder and rectum) is the minimum, and the treatment is applied on the device.