Research the standard and "field-in-field mantle" technique to radiotherapy of hodgkin's disease in human-like phantom by dosimetric method

Objective: The standard (3D-CRT) and Field-In-Field (FIF) Mantle technique in RT of Hodgkin's disease was investigated in human-like phantom by dosimetric method. To RT plans with standard and FIF technique were created, the data obtained in human-like phantom based on the target volume dose, HI and CI parameters and in-vivo dosimetric data were compared and the most appropriate treatment plan created by these two techniques was determined. Method: In Department of Radiation Oncology, Akdeniz University Medical Faculty Hospital the images of axial CT scan of the Alderson brand human-like phantom with breast structure were obtained by GE Light Speed RT Computed Tomography Device. CTV and OARs were contoured on these CT images. Using the data of 6 and/or 10 MV energy photon beams of the Elekta Synergy Platform Linear Accelerator Device, totally 6 different treatment plan using 3D-CRT and FIF technique were created for the human-like phantom in the Monaco TPS. For the quality control of the treatment plans, the point absolute dose and the two-dimensional dose distributions were examined with ion chamber and MatriXX respectively. The Gafchromic films that placed between 14-15th section of the phantom and additionally fixed on the right and left breast tissue and then the treatment plans irradiaton were performed and the dose and dose distributions were evaluated. Results: The FIF technique generally provided a more homogeneous dose distribution in PTV when Standard and FIF planning techniques were applied in. However, in the AP / PA (6 MV) plan, which is the most suitable among the 6 different plans, the total treatment dose was measured as approximately 18 to 50 Gy for the right and left breast, respectively. Conclusion: In the radiotherapy of Hodgkin's disease, the FIF technique with the AP / PA (6 MV) could be applied among the other 6 different plans, while it constitutes a risk in the breast tissue regarding to the total treatment doses in all plans. Key words: Field-In-Field Technique, Film Dosimetry, Hodgkin Lymphoma, Human-Like Phantom, Mantle Field Radiotherapy