Structurally-constrained optical-flow-guided adversarial generation of synthetic CT for MR-only radiotherapy treatment planning.

The rapid progress in image-to-image translation methods using deep neural networks has led to advancements in the generation of synthetic CT (sCT) in MR-only radiotherapy workflow. Replacement of CT with MR reduces unnecessary radiation exposure, financial cost and enables more accurate delineation of organs at risk. Previous generative adversarial networks (GANs) have been oriented towards MR to sCT generation. In this work, we have implemented multiple augmented cycle consistent GANs. The augmentation involves structural information constraint (StructCGAN), optical flow consistency constraint (FlowCGAN) and the combination of both the conditions (SFCGAN). The networks were trained and tested on a publicly available Gold Atlas project dataset, consisting of T2-weighted MR and CT volumes of 19 subjects from 3 different sites. The network was tested on 8 volumes acquired from the third site with a different scanner to assess the generalizability of the network on multicenter data. The results indicate that all the networks are robust to scanner variations. The best model, SFCGAN achieved an average ME of 0.9   5.9 HU, an average MAE of 40.4   4.7 HU and 57.2   1.4 dB PSNR outperforming previous research works. Moreover, the optical flow constraint between consecutive frames preserves the consistency across all views compared to 2D image-to-image translation methods. SFCGAN exploits the features of both StructCGAN and FlowCGAN by delivering structurally robust and 3D consistent sCT images. The research work serves as a benchmark for further research in MR-only radiotherapy.

Time-Driven Activity-Based Costing Comparison of Stereotactic Radiosurgery to Multiple Brain Lesions Using Single-Isocenter Versus Multiple-Isocenter Technique.

PURPOSE: Stereotactic radiosurgery (SRS) historically has been used to treat multiple brain lesions using a multiple-isocenter technique-frequently associated with significant complexity in treatment planning and long treatment times. Recently, given innovations in planning algorithms, patients with multiple brain lesions may now be treated with a single-isocenter technique using fewer total arcs and less time spent during image guidance (though with stricter image guided radiation therapy tolerances). This study used time-driven activity-based costing to determine the difference in cost to a provider for delivering SRS to multiple brain lesions using single-isocenter versus multiple-isocenter techniques. METHODS AND MATERIALS: Process maps, consisting of discrete steps, were created for each phase of the SRS care cycle and were based on interviews with department personnel. Actual treatment times (including image guidance) were extracted from treatment record and verify software. Additional sources of data to determine costs included salary/benefit data of personnel and average list price/maintenance costs for equipment. RESULTS: Data were collected for 22 patients who underwent single-isocenter SRS (mean lesions treated, 5.2; mean treatment time, 30.2 minutes) and 51 patients who underwent multiple-isocenter SRS (mean lesions treated, 4.4; mean treatment time, 75.2 minutes). Treatment time for multiple-isocenter SRS varied substantially with increasing number of lesions (11.8 minutes/lesion; P < .001), but to a much lesser degree in single-isocenter SRS (1.8 minutes/lesion; P = .029). The resulting cost savings from single-isocenter SRS based on number of lesions treated ranged from $296 to $3878 for 2 to 10 lesions treated. The 2-mm planning treatment volume margin used with single-isocenter SRS resulted in a mean 43% increase of total volume treated compared with a 1-mm planning treatment volume expansion. CONCLUSIONS: In a comparison of time-driven activity-based costing assessment of single-isocenter versus multiple-isocenter SRS for multiple brain lesions, single-isocenter SRS appears to save time and resources for as few as 2 lesions, with incremental benefits for additional lesions treated.

Low-Cost iPhone-Assisted Processing to Obtain Radiotherapy Bolus Using Optical Surface Reconstruction and 3D-Printing.

Patient specific boluses can increase the skin dose distribution better for treating tumors located just beneath the skin with high-energy radiation than a flat bolus. We introduce a low-cost, 3D-printed, patient-specific bolus made of commonly available materials and easily produced using the "structure from motion" and a simple desktop 3D printing technique. Nine pictures were acquired with an iPhone camera around a head phantom. The 3D surface of the phantom was generated using these pictures and the "structure from motion" algorithm, with a scale factor calculated by a sphere fitting algorithm. A bolus for the requested position and shape based on the above generated surface was 3D-printed using ABS material. Two intensity modulated radiation therapy plans were designed to simulate clinical treatment for a tumor located under the skin surface with a flat bolus and a printed bolus, respectively. The planned parameters of dose volume histogram, conformity index (CI) and homogeneity index (HI) were compared. The printed bolus plan gave a dose coverage to the tumor with a CI of 0.817 compared to the CI of 0.697 for the plan with flat bolus. The HIs of the plan with printed bolus and flat bolus were 0.910 and 0.887, respectively.

Clinical utility and value contribution of an MRI-positive line marker for image-guided brachytherapy in gynecologic malignancies.

PURPOSE: The purpose of this study was to investigate the utility of a novel MRI-positive line marker, composed of C4:S (cobalt chloride-based contrast agent) encapsulated in high-density polyethylene tubing, in permitting dosimetry and treatment planning directly on MRI. METHODS AND MATERIALS: We evaluated the clinical feasibility of the C4:S line markers in nine sequential brachytherapy procedures for gynecologic malignancies, including six tandem-and-ovoid and three interstitial cases. We then quantified the internal resource utilization of an intraoperative MRI-guided procedural episode via time-driven activity-based costing, identifying opportunities for cost-containment with use of the C4:S line markers. RESULTS: The C4:S line markers demonstrated the strongest positive signal visibility on 3D constructive interference in steady state (CISS)/FIESTA-C followed by T1-weighted sequences, permitting accurate delineation of the applicator lumen and thus the source path. These images may be fused along with traditional T2-weighted sequences for optimal tumor and anatomy contouring, followed by treatment planning directly on MRI. By eliminating postoperative CT for fusion and applicator registration from the procedural episode, use of the C4:S line markers could decrease workflow time and lower total delivery costs per procedure. CONCLUSIONS: This analysis supports the clinical utility and value contribution of the C4:S line markers, which permit accurate MRI-based dosimetry and treatment planning, thereby eliminating the need for postoperative CT for fusion and applicator registration.

Time-driven activity-based costing of adjuvant vaginal cuff brachytherapy for uterine cancer in an integrated brachytherapy suite.

PURPOSE: Adjuvant vaginal cuff brachytherapy is well tolerated and reduces the risk of local recurrence in endometrial cancer. However, there is provider variation in the number of radiation treatments, which ranges from three to six fractions. Using time-driven activity-based costing, we calculated the cost to deliver three vs six fractions to determine the value of each regimen at our brachytherapy suite with CT-on-rails. METHODS AND MATERIALS: Process maps were created to represent each step from initial consult to completion of therapy. Components of care included personnel, equipment, and consumable supplies. The capacity cost rate was determined for each resource and calculated for each regimen. RESULTS: The total direct costs to deliver three- and six-fraction treatment courses were $1,415 and $2,227, respectively. Personnel cost accounted for 63% of overall expenditures. Computed tomography simulation and planning, required for the first fraction, cost $232 for both regimens. Duties of the procedural nurse (scheduling, patient setup, and turnover) consumed the most time at 35% of total personnel minutes. CONCLUSIONS: Time-driven activity-based cost analysis revealed a 57% relative increase, but modest absolute increase, in delivery costs for six vs three fractions of brachytherapy at our institution. This current analysis may influence considerations of the relative value between the two treatment schedules, but this methodology should not be interpreted as informative for reimbursement policy evaluation.

SUPR-3D: A randomized phase iii trial comparing simple unplanned palliative radiotherapy versus 3d conformal radiotherapy for patients with bone metastases: study protocol.

BACKGROUND: Bone metastases in the lower spine and pelvis are effectively palliated with radiotherapy (RT), though this can come with side effects such as radiation induced nausea and vomiting (RINV). We hypothesize that high rates of RINV occur in part because of the widespread use of inexpensive simple unplanned palliative radiotherapy (SUPR), over more complex and resource intensive 3D conformal RT, such as volumetric modulated arc therapy (VMAT). METHODS: This is a randomized, multi-centre phase III trial of SUPR versus VMAT. We will accrue 250 patients to assess the difference in patient-reported RINV. This study is powered to detect a difference in quality of life between patients treated with VMAT vs. SUPR. DISCUSSION: This trial will determine if VMAT reduces early toxicity compared to SUPR and may provide justification for this more resource-intensive and costly form of RT. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03694015 . Date of registration: October 3, 2018.

The Financial Impact of Fractionation Scheme and Treatment Planning Method for Rectal Cancer in the United States.

BACKGROUND: Preoperative long-course chemoradiotherapy (CRT) and short-course radiotherapy (SCR) for locally advanced rectal cancer (LARC) were found to have equivalent outcomes in 3 randomized trials. SCR has not been widely adopted in the United States (US). Three-dimensional (3D) treatment planning is standard, whereas intensity-modulated radiotherapy (IMRT) is controversial. In this study, we assessed the economic impact of fractionation scheme and planning method for payers in the US. MATERIALS AND METHODS: We performed a population-based analysis of the total cost of radiotherapy for LARC in the US annually. The national annual target population was calculated using the Surveillance, Epidemiology, and End Results database. Radiotherapy costs were based on billing codes and 2018 pricing by Medicare's Hospital Outpatient Prospective Payment System. RESULTS: We estimate that 12,945 patients with LARC are treated with radiotherapy annually in the US. The cost of CRT with 3D or IMRT is US $15,882 and $23,745 per patient, respectively. With SCR, the cost with 3D or IMRT is $5,458 and $7,323 per patient, respectively. The use of SCR would lead to 53% to 77% annual savings of $106,168,871 to $232,105,727 compared with CRT. IMRT increases the total cost of treatment by 34% to 50%, and if adopted widely, would lead to an excess cost of $24,152,134 and $101,784,723 annually with SCR and CRT, respectively. CONCLUSIONS: SCR may have the potential to save approximately US $106 to t232 million annually in the US, likely without impacting outcomes. Lack of evidence showing benefit with costly IMRT should limit its use to clinical trials. It would be reasonable for public and private payers to consider which type of radiation is most suited to reimbursement.

Automated Instead of Manual Treatment Planning? A Plan Comparison Based on Dose-Volume Statistics and Clinical Preference.

PURPOSE: Automated planning aims to speed up treatment planning and improve plan quality. We compared manual planning with automated planning for lung stereotactic body radiation therapy based on dose-volume histogram statistics and clinical preference. METHODS AND MATERIALS: Manual and automated intensity modulated radiation therapy plans were generated for 56 patients by use of software developed in-house and Pinnacle 9.10 Auto-Planning, respectively. Optimization times were measured in 10 patients, and the impact of the automated plan (AP) on the total treatment cost was estimated. For the remaining 46 patients, each plan was checked against our clinical objectives, and a pair-wise dose-volume histogram comparison was performed. Three experienced radiation oncologists evaluated each plan and indicated their preference. RESULTS: APs reduced the average optimization time by 77.3% but only affected the total treatment cost by 3.6%. Three APs and 0 manual plans failed our clinical objectives, and 13 APs and 9 manual plans showed a minor deviation. APs significantly reduced D2% (2% of the volume receives a dose of at least D2%) for the spinal cord, esophagus, heart, aorta, and main stem bronchus (P < .05) while preserving target coverage. The radiation oncologists found >75% of the APs clinically acceptable without any further fine-tuning. CONCLUSIONS: APs may help to create satisfactory treatment plans quickly and effectively. Because critical appraisal by qualified professionals remains necessary, there is no such thing as "fully automated" planning yet.

Monte Carlo verification of radiotherapy treatments with CloudMC.

BACKGROUND: A new implementation has been made on CloudMC, a cloud-based platform presented in a previous work, in order to provide services for radiotherapy treatment verification by means of Monte Carlo in a fast, easy and economical way. A description of the architecture of the application and the new developments implemented is presented together with the results of the tests carried out to validate its performance. METHODS: CloudMC has been developed over Microsoft Azure cloud. It is based on a map/reduce implementation for Monte Carlo calculations distribution over a dynamic cluster of virtual machines in order to reduce calculation time. CloudMC has been updated with new methods to read and process the information related to radiotherapy treatment verification: CT image set, treatment plan, structures and dose distribution files in DICOM format. Some tests have been designed in order to determine, for the different tasks, the most suitable type of virtual machines from those available in Azure. Finally, the performance of Monte Carlo verification in CloudMC is studied through three real cases that involve different treatment techniques, linac models and Monte Carlo codes. RESULTS: Considering computational and economic factors, D1_v2 and G1 virtual machines were selected as the default type for the Worker Roles and the Reducer Role respectively. Calculation times up to 33 min and costs of 16 € were achieved for the verification cases presented when a statistical uncertainty below 2% (2σ) was required. The costs were reduced to 3-6 € when uncertainty requirements are relaxed to 4%. CONCLUSIONS: Advantages like high computational power, scalability, easy access and pay-per-usage model, make Monte Carlo cloud-based solutions, like the one presented in this work, an important step forward to solve the long-lived problem of truly introducing the Monte Carlo algorithms in the daily routine of the radiotherapy planning process.

A Medicare cost analysis of MRI- versus CT-based high-dose-rate brachytherapy of the cervix: Can MRI-based planning be less costly?

PURPOSE: While some institutions deliver multiple fractions per implant for MRI-based planning, it is common for only one fraction to be delivered per implant with CT-based cervical brachytherapy. The purpose of this study was to compare physician costs, hospital costs, and overall costs for cervical cancer patients treated with either CT-based or MRI-based high-dose-rate (HDR) cervical brachytherapy to determine if MRI-based brachytherapy as described can be financially feasible. METHODS AND MATERIALS: We identified 40 consecutive patients treated with curative intent cervical brachytherapy. Twenty patients underwent CT-based HDR brachytherapy with five fractions delivered in five implants on nonconsecutive days in an outpatient setting with the first implant placed with a Smit sleeve under general anesthesia. Twenty patients received MRI-based HDR brachytherapy with four fractions delivered in two implants, each with MRI-based planning, performed 1-2 weeks apart with an overnight hospital admission for each implant. We used Medicare reimbursements to assess physician costs, hospital costs, and overall cost. RESULTS: The median cost of MRI-based brachytherapy was $14,248.75 (interquartile range [IQR]: $13,421.32-$15,539.74), making it less costly than CT-based brachytherapy with conscious sedation (i.e., $18,278.85; IQR: $17,323.13-$19,863.03, p < 0.0001) and CT-based brachytherapy with deep sedation induced by an anesthesiologist (i.e., $27,673.44; IQR: $26,935.14-$29,511.16, p < 0.0001). CT-based brachytherapy with conscious sedation was more costly than CT-based brachytherapy with deep sedation (p < 0.001). CONCLUSIONS: MRI-based brachytherapy using the described treatment course was less costly than both methods of CT-based brachytherapy. Cost does not need to be a barrier for MRI-based cervical brachytherapy, especially when delivering multiple fractions with the same application.

Development of a virtual spacer to support the decision for the placement of an implantable rectum spacer for prostate cancer radiotherapy: Comparison of dose, toxicity and cost-effectiveness.

INTRODUCTION: Previous studies have shown that the implantable rectum spacer (IRS) is not beneficial for all patients. A virtual IRS (V-IRS) was constructed to help identify the patients for whom it is cost-effective to implant an IRS, and its viability as a tool to tailor the decision of an IRS implantation to be beneficial for the specified patient was assessed. Please watch animation: (https://www.youtube.com/watch?v=tDlagSXMKqw) MATERIALS AND METHODS: The V-IRS was tested on 16 patients: 8 with a rectal balloon implant (RBI) and 8 with a hydrogel spacer. A V-IRS was developed using 7 computed tomography (CT) scans of patients with a RBI. To examine the V-IRS, CT scans before and after the implantation of an IRS were used. IMRT plans were made based on CT scans before the IRS, after IRS and with the V-IRS, prescribing 70 Gray (Gy) to the planning target volume. Toxicity was accessed using externally validated normal tissue complication probability (NTCP) models, and the Cost-effectiveness was analyzed using a published Markov model. RESULTS: The rectum volume receiving 75Gy (V75) were improved by both the IRS and the V-IRS with on average 4.2% and 4.3% respectively. The largest NTCP reduction resulting from the IRS and the V-IRS was 4.0% and 3.9% respectively. The RBI was cost-effective for 1 out of 8 patients, and the hydrogel was effective for 2 out of 8 patients, and close to effective for a third patient. The classification accuracy of the model, regarding cost-effectiveness, was 100%. CONCLUSION: The V-IRS approach in combination with a toxicity prediction model and a cost-effectiveness analyses is a promising basis for a decision support tool for the implantation of either a hydrogel spacer or a rectum balloon implant.

An Automated Treatment Plan Quality Control Tool for Intensity-Modulated Radiation Therapy Using a Voxel-Weighting Factor-Based Re-Optimization Algorithm.

Intensity-modulated radiation therapy (IMRT) currently plays an important role in radiotherapy, but its treatment plan quality can vary significantly among institutions and planners. Treatment plan quality control (QC) is a necessary component for individual clinics to ensure that patients receive treatments with high therapeutic gain ratios. The voxel-weighting factor-based plan re-optimization mechanism has been proved able to explore a larger Pareto surface (solution domain) and therefore increase the possibility of finding an optimal treatment plan. In this study, we incorporated additional modules into an in-house developed voxel weighting factor-based re-optimization algorithm, which was enhanced as a highly automated and accurate IMRT plan QC tool (TPS-QC tool). After importing an under-assessment plan, the TPS-QC tool was able to generate a QC report within 2 minutes. This QC report contains the plan quality determination as well as information supporting the determination. Finally, the IMRT plan quality can be controlled by approving quality-passed plans and replacing quality-failed plans using the TPS-QC tool. The feasibility and accuracy of the proposed TPS-QC tool were evaluated using 25 clinically approved cervical cancer patient IMRT plans and 5 manually created poor-quality IMRT plans. The results showed high consistency between the QC report quality determinations and the actual plan quality. In the 25 clinically approved cases that the TPS-QC tool identified as passed, a greater difference could be observed for dosimetric endpoints for organs at risk (OAR) than for planning target volume (PTV), implying that better dose sparing could be achieved in OAR than in PTV. In addition, the dose-volume histogram (DVH) curves of the TPS-QC tool re-optimized plans satisfied the dosimetric criteria more frequently than did the under-assessment plans. In addition, the criteria for unsatisfied dosimetric endpoints in the 5 poor-quality plans could typically be satisfied when the TPS-QC tool generated re-optimized plans without sacrificing other dosimetric endpoints. In addition to its feasibility and accuracy, the proposed TPS-QC tool is also user-friendly and easy to operate, both of which are necessary characteristics for clinical use.

[A microcost analysis of radiation therapy of localized prostate cancer]. / A prosztatadaganatos betegek sugárterápiájának mikroköltség-számítása.

INTRODUCTION: Development of radiation technology provides new opportunities for the treatment of prostate cancer, but little is known about the costs of novel technologies. AIM: The aim of this analysis was to compare the costs of conventional three-dimensional radiation therapy to normal and hypofractionated intensity-modulated radiation therapy for the treatment of localized prostate cancer. METHOD: The cost-analysis was performed based on the data of a Hungarian oncology center from health care provider's perspective. Irradiation time was assessed from the data of 100 fractions delivered in 20 patients. Unit costs for each component were calculated based on actual costs retrieved from the accounting system of the oncology center. RESULTS: Average treatment delivery times were 14.5 minutes for three-dimensional radiation therapy, 16.2 minutes for intensity-modulated radiation therapy with image-guided and 14 minutes without image-guided method. Expected mean cost of patients undergoing conventional three-dimensional radiation therapy, normal and hypofractionated intensity-modulated radiation therapy were 619 000 HUF, 933 000 HUF and 692 000 HUF, respectively. CONCLUSIONS: Although normal and hypofractionated intensity-modulated radiation therapies have already been proven to be cost-effective, current reimbursement rates do not encourage healthcare providers to use the more effective therapy techniques.

Deformable image registration of CT images for automatic contour propagation in radiation therapy.

Radiotherapy treatment plan may be replanned due the changes of tumors and organs at risk (OARs) during the treatment. Deformable image registration (DIR) based Computed Tomography (CT) contour propagation in the routine clinical setting is expected to reduce time needed for necessary manual tumors and OARs delineations and increase the efficiency of replanning. In this study, a DIR method was developed for CT contour propagation. Prior structure delineations were incorporated into Demons DIR, which was represented by adding an intensity matching term of the delineated tissues pairs to the energy function of Demons. The performance of our DIR was evaluated with five clinical head-and-neck and five lung cancer cases. The experimental results verified the improved accuracy of the proposed registration method compared with conventional registration and Demons DIR.

A cost-effective technique for cardiac sparing with deep inspiration-breath hold (DIBH).

Deep inspiration breath hold (DIBH) is an effective technique to reduce cardiac and pulmonary dose during breast radiotherapy (RT). However, as a result of expense and the technical challenges of program implementation, DIBH has not been widely adopted in clinical practice. This report describes a program for DIBH this is relatively inexpensive to implement and has little impact on patient throughput. Multiple redundant mechanisms are incorporated to assure accurate and safe delivery of RT during DIBH. Laser alignment verifies that chest wall excursion is reliably reproduced and maintained during treatment. Chest wall excursion is also monitored independently using an infrared camera trained on a reflective marker on the chest wall. This system automatically triggers "beam off" in the event of movement of the target beyond pre-determined thresholds. Finally, physician review of cine imaging obtained during treatment provides an off-line verification of accurate RT delivery. The approach described herein lowers the investment necessary for implementation of DIBH and may facilitate broader adoption of this valuable technique.

A GPU-accelerated and Monte Carlo-based intensity modulated proton therapy optimization system.

PURPOSE: Conventional spot scanning intensity modulated proton therapy (IMPT) treatment planning systems (TPSs) optimize proton spot weights based on analytical dose calculations. These analytical dose calculations have been shown to have severe limitations in heterogeneous materials. Monte Carlo (MC) methods do not have these limitations; however, MC-based systems have been of limited clinical use due to the large number of beam spots in IMPT and the extremely long calculation time of traditional MC techniques. In this work, the authors present a clinically applicable IMPT TPS that utilizes a very fast MC calculation. METHODS: An in-house graphics processing unit (GPU)-based MC dose calculation engine was employed to generate the dose influence map for each proton spot. With the MC generated influence map, a modified least-squares optimization method was used to achieve the desired dose volume histograms (DVHs). The intrinsic CT image resolution was adopted for voxelization in simulation and optimization to preserve spatial resolution. The optimizations were computed on a multi-GPU framework to mitigate the memory limitation issues for the large dose influence maps that resulted from maintaining the intrinsic CT resolution. The effects of tail cutoff and starting condition were studied and minimized in this work. RESULTS: For relatively large and complex three-field head and neck cases, i.e., >100,000 spots with a target volume of ∼ 1000 cm(3) and multiple surrounding critical structures, the optimization together with the initial MC dose influence map calculation was done in a clinically viable time frame (less than 30 min) on a GPU cluster consisting of 24 Nvidia GeForce GTX Titan cards. The in-house MC TPS plans were comparable to a commercial TPS plans based on DVH comparisons. CONCLUSIONS: A MC-based treatment planning system was developed. The treatment planning can be performed in a clinically viable time frame on a hardware system costing around 45,000 dollars. The fast calculation and optimization make the system easily expandable to robust and multicriteria optimization.

Outcome impact and cost-effectiveness of quality assurance for radiotherapy planned for the EORTC 22071-24071 prospective study for head and neck cancer.

INTRODUCTION: One of the goals of Quality Assurance in Radiotherapy (QART) is to reduce the variability and uncertainties related to treatment planning and beam delivery. The purpose of this study was to assess the outcome impact and cost-effectiveness (CE) of various QART levels for a head and neck (H&N) cancer study. MATERIALS AND METHODS: QART levels were defined as: basic QART with a dummy run (level 2), level 2 plus prospective Individual Case Reviews (ICRs) for 15% of patients (level 3) and level 2 plus prospective ICRs for all patients (level 4). The follow-up of patients was modeled using a multi-state model with parameters derived from EORTC, TROG and RTOG prospective studies. Individual patient data, linking QART results with outcome, were retrieved from the TROG database. Results for each QART level were expressed as percentage of mortality and local failure at 5 years. RESULTS: Quality-of-life-adjusted and recurrence-free survival increased with increasing QART levels. The increase of all these metrics was more sizeable with an increased QART level from 2 or 3 to 4. The estimated quality-adjusted-life-years (QALYs) for an increase of QART levels of 3-4 and 2-4 were 0.09 and 0.15, respectively. The incremental CE ratio was €5525 and €3659 Euros per QALY for these QART levels. Compared to QART level 2 or 3, level 4 was cost-effective. CONCLUSIONS: Increasing QART levels resulted in better patient outcome in this simulated study. The increased complexity of the QART program was also cost-effective.

Evaluating the attendance of medical staff and room occupancy during palliative radiotherapy.

INTRODUCTION: Attendance of staff and use of resources during treatment have an impact on costs. For palliative radiotherapy, no reliable data are available on the subject. Therefore, the measurement of selected variables (staff absorbance and room occupancy) based on daily palliative irradiation was the aim of our prospective study. The analysis is part of a larger study conducted by the German Society of Radiation Oncology (DEGRO). PATIENTS, MATERIAL, AND METHODS: A total of 172 palliative radiation treatments were followed up prospectively between October 2009 and March 2010. The study was performed at two experienced radiotherapy departments (Herne and Bielefeld) and evaluated the attendance of medical personnel and room occupancy related to the selected steps of the treatment procedure: treatment planning and daily application of radiation dose. RESULTS: Computed tomography for treatment planning engaged the unit for 19 min (range: 17-22 min). The localization of target volume required on average 28 min of a technician's working time. The mean attendance of the entire staff (radiation oncologist, physicist, technician) for treatment planning was 159 min, while the total room occupancy was 140 min. Depending on the type of treatment, the overall duration of a radiotherapy session varied on average between 8 and 18 min. The staff was absorbed by the first treatment session (including portal imaging) for 8-27 min. Mean room occupancy was 18 min (range: 6-65 min). The longest medical staff attendance was observed during an initial irradiation session (mean: 11 min). Radiotherapy sessions with weekly performed field verifications occupied the rooms slightly longer (mean: 10 min, range: 4-25 min) than daily radiotherapy sessions (mean: 9 min, range: 3-29 min). We observed that the patients' symptoms, their condition, and their social environment confounded the time schedule. CONCLUSIONS: Target localization, treatment planning, and performance of palliative radiotherapy absorb resources to an extent comparable to nonpalliative treatment. Because of unexpected events, the time schedule before and during radiotherapy may reveal strong interindividual variability.