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3D printing technology was capable of fabricating phantoms to enhance quality assurance in radiation therapy. The ideal phantom has properties equivalent to the real tissue. However, 3D Printing has the limits to mimicking the attenuation properties of various tissues because during 3D printing there can be only one type of material. The purpose of this study was to evaluate the effect of infill percentage and infill patterns of 3D printing technology to simulate various types of tissue. This study used 25 samples measuring 5 × 5 × 1 cm3 from PETG material. The 20 samples were printed using variations infill percentages from 5 - 100% and the infill pattern in lines. The five samples were then printed with the infill percentage constant at 50% and used the infill pattern triangles, grid, gyroid, octet, and concentric. We used Computed Tomography (CT) to determine the Hounsfield Unit (HU) value for each sample and evaluated the suitability of each sample for phantom applications in radiation therapy and radiology. However, none of the samples was able to simulate compact bone. As a result, we found that PETG material could simulate the properties of soft tissue, fat, lung, kidney, liver, pancreas, and spongy bone. Thus, the study had shown promising potential for the fabrication of the anthropomorphic phantom of radiation therapy.

Blood cancer causes a significant increase in the concentration of Leukocytes, which can be broken down through dielectrophoresis and electrochemical procedures. Therefore, the electric field plays an important role in the migration of leukocytes to high voltage areas. This is because different electrode arrangements produce varying electric field distributions. Furthermore, this study applied finite element methods to generate electric fields when electrodes with an AC voltage were applied to blood placed in a chamber. Therefore, in this study, variations of mediums and electrode arrangements were investigated, which led to the recommendation of 3 models. The objective was to investigate electrode arrangements that produce optimal electric field distribution for the three models to exhibit a booster of electric field distribution. The maximum electric field is generated close to the electrode (Z=2 mm and Z=92 mm) for any material (i.e. normal blood, B lymphocyte, and T lymphocyte) with values of 22.6 V/m and 23.47 V/m, 22.85 V/m and 22.97 V/m, and 24.88 V/m and 25.01 V/m. Based on principle, lymphocytes in the blood result in positive dielectrophoresis, since they migrate to a higher electric field close to the electrode, with enough input voltage to turn the electrochemical process on the leukocytes into electric current. Furthermore, this study provides new perspectives and ideas, which have not been revealed in previous studies on blood cancer therapy using the electric field of Ag electrode in blood cancer distribution. Keywords: blood cancer, dielectrophoresis, electric field, voltage, electrochemical, and cancer therapy.

The delivery of radiation therapy to patients requires prior planning made by medical physicists to achieve radiotherapy goals. Radiotherapy has a plan to eradicate the growth of cancer cells by giving high doses and minimizing the radiation dose to normal tissue. Evaluation of planning is generally done based on dosimetric parameters, such as minimum dose, maximum dose, and means dose obtained from the DVHs data. Based on the same DVHs, data were evaluate dinterms of biological effects to determine the highest possible toxicity in normal tissue after the tumor had been treated with radiation using the NTCP model. The evaluation was conducted by selecting three DICOM-RT data of post-mastectomy right breast cancer patients who had been prescribed a dose of 50 Gy obtained from the Hospital MRCCC Siloam Semanggi database. All data were processed using open-source software DICOManTX to get the DVH and isodose information. Matlab-based CERR software was used to calculate the NTCP model. The results show that the three patients' DVH and isodose treatment planning result in a homogeneous dose distribution result because the PTV area obtains adose limit of ≥ 95%. Moreover, normalt issue still gets adose below the tolerance limit based on the standard from RTOG 1005 and ICRU 83. Analysis of NTCP shows a complication probability below 1% for each organ, suggesting that any organ which has been irradiated has a low likelihood of complications. Therefore, it can be concluded that the treatment planning which has been made in the three patients using the IMRT technique has achieved the objectives of radiotherapy, which is to minimize toxicity to healthy organs. Keywords: DVH, isodose, NTCP, radiotherapy.