Metastatik prostat kanseri hastalarında 177LU[LU]-PSMA-617'nin görüntü bazlı kırmızı kemik iliği biyodağılımı ve dozimetrisi

177Lu[Lu]-PSMA-617 therapy applied in the nuclear medicine department is a very promising treatment for metastatic castration-resistant prostate cancer patients for treatment response, so it has become very popular recently. 177Lu[Lu]-PSMA-617, which has recently received FDA and EMA approval, is not among the standardized nuclear medicine treatments; therefore, it is essential to apply patient-specific personalized dosimetry for this application. PSMA, an antigen with specific uptake property for prostate cancers, is combined with 177Lu radionuclide and injected into patients. Because of the physical properties of the 177Lu radionuclide, it is possible to perform 177Lu[Lu]-PSMA-617 dosimetry by using nuclear medicine imaging techniques. As a result, the absorption dose values of the relevant organs and tumors can be calculated in order to determine how much damage is caused to the tumor and healthy organs as a result of the treatment applied. Calculation of the absorb dose value of the bone marrow, which is specified as the organ at risk in the treatment of 177Lu[Lu]-PSMA-617, is an important criterion in documenting the reliability of the applied treatment and planning the subsequent 177Lu[Lu]-PSMA-617 treatments. The main purpose of the applied dosimetry is to cause maximum damage to tumors while causing as little damage to healthy tissues as possible. Bone marrow dosimetry can be performed in two different ways: using blood measurements or nuclear medicine imaging techniques. There is no standardized or proven method in this regard. In this thesis, image-based dosimetry method was used for bone marrow dosimetry. The post-treatment bone marrow doses of patients with metastatic castration-resistant prostate cancer treated with 177Lu[Lu]-PSMA-617 included in the thesis study were calculated using different scanning modes. These scanning modes were performed using multiple 3D images (scanning mode 1), multiple 2D images and one 3D image (scanning mode 2), and a single 3D image (scanning mode 1). Bone marrow absorb dose values obtained due to three different scanning modes were compared with each other and with previously published literature data. This is the first study to calculate and compare personalized bone marrow absorb dose values using 3 different scanning modes in patients treated with 177Lu[Lu]-PSMA-617. Key Words: Image based dosimetry, Bone marrow dosimetry, Lutetium