60-year-old woman was treated for a brain metastasis. The pa ent received Intensity-modulated radia on therapy (SIB-IMRT) dose of 30 Gy for the whole brain and 40 Gy delivered simultaneously to individual brain metastases in 10 frac ons. The present report inves gated the influence of applied novel prepared treatment plan, among others the frac ona on protocol on the electroencephalogram (EEG) record.

Background: Intensity Modulated Radiation Therapy (IMRT) is extensively used in the treatment of malignancies. Clarkson’ s method is one of the leading methods for dose calculation at open points present in irregular fields. Objective: The aim of this study is to generalize the Clarkson’ s method for dose calculation at points under compensator filters in IMRT method and its application in IMRT quality control as well. Material and Methods: In this experimental study, compensator filters were designed in two forms: flat filter and block piled-up compensator. The measurements for the compensator filters and open fields in 5 and10 cm depths at energy levels (6, 10 and 18 MV) and in fields with different dimensions were performed using “ Mapcheck2” dosimeter. The aim of performing calculations is to derive the theoretical dose by the generalized Clarkson’ s equation and comparing it with data resulted from the measurement for confirming the Clarkson’ s equation presented. Results: These results demonstrate the data derived from the generalized Clarkson’ s method are in good agreement with the data resulted from measurement; the highest error of the proposed equation was 3% for flat filter, and less than 5% for block-piled-up filter. Higher error in the block-piled-up filter compared with the flat filter was due to the presence of leakage between these blocks. Conclusion: The results of this study demonstrated that the presented equation is reliable and valid, and the proposed equation can be applied for dose calculation at all points under the compensator filter or the shielded areas.

Background: Cancer is the second most common cause of death worldwide. Economic evaluation of cancer treatment to reduce costs can save the health care system millions of dollars while optimizing care. Therefore, this systematic review aimed to study the economic evaluation of cancer treatment using intermediate intensity radiation therapy (IMRT) compared to conventional 3D conformal radiation therapy (3D-CRT). Methods: Literatures from PubMed, Embase, Cochran Library, Google scholar, Scopus and Iranian databases were retrieved since Jan 2000 to Apr 2020 for eligible English studies. The quality of the studies was evaluated using Cheers' checklist and then the textual data were analyzed manually by content analysis method. Results: Overall, 1790 articles were retrieved, of which 12 studies were reviewed. The article quality score ranged from 14. 5 to 23 out of a maximum of 24 points. Eleven studies referred to cost-effectiveness analysis and one study referred to cost-utility analysis. Studies have been conducted in the United States, Canada, Australia, Brazil, the Netherlands, the United Kingdom, and Hungary. IMRT appears to be a cost-effective treatment strategy for rectal cancer, soft tissue sarcoma, and localized carcinoma of the pharynx, and for prostate cancer in terms of prolonging survival, but it is a cost-effective treatment strategy for head cancer. In addition, the neck was not in India's cancer control program. Conclusion: The results can help to decide whether to use radiation therapy and radiotherapy in the standard treatment path. Furthermore, they underline that IMRT treatment technique was cost effective for a long-time care service.

Background: In head and neck radiotherapy, immobilization devices can affect dose delivery. In this study, a comprehensive end-to-end test was developed to evaluate the accuracy of radiotherapy treatment. Materials and Methods: An Alderson Radiation Therapy (ART) anthropomorphic phantom with EBT3 film was used to mimic the actual patient treatment process. Ten patients treated for nasopharyngeal carcinomas with IMRT were retrospectively selected. For each patient, the treatment plan, as well as the targets and OARs was transplanted onto the phantom, and the IMRT plan was subsequently recalculated to the phantom with EBT3 film. Two quality assurance (QA) plans were generated, namely “ Plan-with” wherein the immobilization device was contoured and “ Plan-without” wherein it was omitted. EBT3 measurements were compared with the results of the TPS calculation. Results: With different gamma calculation criteria applied, the results obtained for Plan-with were closer to the dose measured with the EBT3 film. Moreover, 1. 8% deviation was observed in the posterior neck skin dose for Plan-with when compared to the film measurements while the value was 33. 1% lower for Plan-without. When compared to Plan-without, each target volume in Plan-with exhibited a 1– 4% reduction in the maximum dose (D2%), minimum dose (D98%) and mean dose (Dmean). Conclusion: Immobilization devices decrease the radiation dose to target volumes while increasing the skin dose and should be included within the body contour to ensure an accurate planning dose. The end-to-end IMRT test using an ART anthropomorphic phantom is a valuable tool to identify discrepancies between calculated and delivered radiation doses.

Introduction: The purpose of this study is to evaluate and compare treatment plan quality metrics for postmastectomy breast cancer patients using 3-Dimensional conformal radiotherapy (3DCRT) and intensitymodulated radiotherapy (IMRT) planning techniques. Material and Methods: The current study included 50 postmastectomy breast cancer patients out of which 24 were planned with 3DCRT and 26 with IMRT technique. Treatment plan quality metrics, namely homogeneity index (HI), conformity index (CI), conformation number (CN), uniformity index (UI) and spillage index (R50), volume receiving 110% and 95% of the prescribed dose (V110% and V95%) were calculated and compared for the two planning techniques. Results: IMRT plans have better conformity, homogeneity indices, and lower V110% than 3DCRT plans with an almost similar R50% and V95%. Conclusion: Quantitative values of radiotherapy treatment plan quality metrics for the target are found in favour of the IMRT technique rather than 3DCRT. Implementation of these five parameters is helpful for evaluating treatment plans along with slice by slice and DVH analysis.

Background: The aim of the study was to compare the dose differences between 3Dprinted bolus, commercial bolus (wax), thermoplastic mask bolus and bolus-free head phantoms simulating nose radiotherapy. Materials and Methods: We used 3D printing technology to make a 3D-printed bolus. To evaluate the clinical feasibility, intensitymodulated radiation therapy (IMRT) plans were created for head phantoms that were 3D-printed bolus, commercial bolus (wax), thermoplastic mask bolus or bolus-free. Dosimetry differences were compared in simulating nose radiotherapy. Results: For the PTV of all the plans, 3D-printed bolus, commercial bolus (wax) and thermoplastic masks bolus had lower Dmax and D1% than the plan without the bolus,for Dmean and D95%, the results were the opposite. For V90%, V95%, V100% and HI, the plan with the 3D-printed bolus was better than the others, and the plan without the bolus was the worst. Conclusions: The dosimetric differences of 3D-printed bolus, commercial bolus (wax), thermoplastic mask bolus and bolus-free were compared in head phantoms simulating nose radiotherapy. The 3D-printed bolus was good for fit, had a high level of comfort and repeatability, and also had better dose parameters in IMRT plans.

Background: The purpose of this study is to compare SOURCE 8 and 20 in the EGSnrc-based DOSXYZnrc Monte Carlo code for Jaws-only intensitymodulated radiation therapy (JO-IMRT) dose distribution, and demonstrate the advantage of SOURCE 20 to SOURCE 8 to treat head-and-neck cancer. Materials and Methods: The clinical photon beams of the HPD Siemens Primus linear accelerator simulated using the BEAMnrc code and then verified by measurement. The phase-space files generated by the BEAMnrc code were used as an input for the DOSXYZnrc to calculate the JO-IMRT dose distributions of patients (in form of CT images) using the SOURCES 8 and 20. The isodose distribution on slices, DVH and gamma index (3%/3 mm, 2%/2 mm, and 1%/1 mm) were compared with Monte Carlo and treatment planning system (TPS) results. Furthermore, the efficient computation of dose distributions such as time running, working load and uncertainty error calculation also considered for evaluation. Results: JO-IMRT dose distributions calculated by SOURCE 8 and 20 compared with the Prowess Panther TPS. The time running, working load based on SOURCE 20 were significantly less than SOURCE 8. Futhermore, the uncertainty calculation based on SOURCE 20 was also significantly less than SOURCE 8. Conclusion: The JO-IMRT dose distributions calculated by SOURCE 20 are more efficient than SOURCE 8.

Background: Mul ple beams are generally used with an increased possibility that the beam axis intersects the treatment table. Treatment tabletops are commonly made of carbon fiber due to its high mechanical strength and rigidity, low specific density, extremely light and low radia on beam a enua on proper es. Purpose of this paper is inves gated the dose changes in the buildup region and beam a enua on by a carbon fiber tabletop for high energy 6-and 18-MV photon beams. Materials and Methods: Measurements were performed for 10 cm × 10 cm and 20 cm × 20 cm field sizes. The surface dose and percentage depth doses (%DD) were measured by a Markus parallel plate chamber at a source-surface distance (SSD) of 100 cm for 6 MV and 18 MV photon beams. A enua on measurements were made at the solid-water phantom for gantry angles of 0o and 180o rota on of the beam. Results: A carbon fiber tabletop increases the surface dose from 12. 87% to 86. 65% for 10 cm x 10 cm and from 8. 72% to 71. 16% for 20 cm × 20 cm field at 6 and 18 MV, respec vely. The surface dose with the carbon fiber tabletop in an open field (0o) increases with field size. Conclusion: The carbon fiber tabletop causes a substan ally increased surface dose, and also significantly decreases the skin-sparing effect, which is clinically important. The dosimetric effect of the tabletop may be higher, especially for the intensitymodulated radia on therapy depending on the beam orienta on.