Failure Mode and Effects Analysis for Treatment Workflow of a Novel Ring Gantry Linac

PURPOSE/OBJECTIVE(S)

A new ring gantry Linac machine combined with a PET ring is available in the market. It has 3 separate centers, one for laser, one for CT imaging and a 3rd for the Linac. As a first-generation machine of its kind, the workflow heavily depends on user-input. As example, it uses two separate coordinate systems, IEC for lasers and CT localization offsets and DICOM for treatment planning. The planner must manually convert between the two systems. We hypothesize that the unique design of the machine that is heavily dependent on users' input increases the potential of failure of treatment. The present work investigates failure modes for treatment delivery using the methodology of failure modes and effects analysis (FMEA) and proposes solutions to mitigate some of the failure modes (FMs).

MATERIALS/METHODS

A group of two radiation oncologists, two radiation therapists and three medical physicists was assembled. The process map for treatment delivery on the X1 was created and FMs were identified. Members independently graded each FM on 3 parameters, likelihood of occurrence, detectability of FM and level of severity on patient treatment. A grading scale of 1-5 was used with five representing the worst outcome in each parameter. Each member also identified the origin of each FM to be human, machine or clinical process. Mitigation solutions were proposed.

RESULTS

The process map of treatment delivery on X1 consists of six major processes and 24 sub-processes. A total of 27 FMs were identified, with many 19/27 (70%) caused by human errors and 7/27 (27%) caused by machine. From all responses, we tallied a median of 11 FMs (40%) that have both S≥ 4 and O or D ≥ 4. To further focus our analysis, we looked at the highest PRN scores from each member and found 7 FMs that were common. 1 FM was in "initiation of Treatment" sub-process and 6 FMs in "Treatment delivery" sub-process. Proposed solutions to these FMs were concerned with software upgrades. Examples are, allow changes in fractionation, allow dose tracking, auto calculation of couch position for various sub processes, allow DICOM image transfer and many more. The current clinical workflow that we adopted for these FMs either puts the burden on the user to confirm/verify parameters or the use of third-party software. In addition to these high-scoring FMs, we adopted changes in clinical workflow to mitigate other FMs, most of them through third-party software.

CONCLUSION

This study confirmed that the unique design and user-dependent machine environment, human failures are high accounting for 70% of FMs in treatment delivery alone. Our current workflow of the machine depends on direct user input to calculate/confirm certain parameters or the use of third-party software, which also depends on the user for proper completion of the task. Suggested solutions also included proposed improvement to the machine's software and user interface.

Conformality Indices and Brain Dose Objective for Multi-Lesion Brain Single Isocenter Linac-Based Stereotactic Radiosurgery

PURPOSE/OBJECTIVE(S)

The lack of recommendation on Linac-based stereotactic radiosurgery (SRS) and radiotherapy (SRT) plan quality for multi-lesion brain metastasis results in planning heterogeneity. The use of MLCs in the delivery is expected to add extra leakage when multi-lesions are treated simultaneously, and no recommendations availability in literature. We aimed to identify conformality indices and plan objectives that would guide multi-brain metastasis SRS & SRT MATERIALS/METHODS: We performed a retrospective analysis of clinically accepted brain metastasis radiotherapy plans treated using SRS and SRT at our department. Each plan was assessed for four metrics: Two conformality indices, including R50% referring to the ratio of the 50% dose cloud to the PTV, and %D1cm referring to the percentage of dose at 1cm away from PTV in any direction. One dose objective, V12 Gy referring to the brain volume receiving 12 Gy, and one delivery efficiency parameter, the modulation factor, defined as the ratio of the total MU to the prescribed dose. Each parameter was evaluated as a function of total PTV volume and number of lesions.

RESULTS

A total of 107 plans were analyzed. The analyzed plans included pre- and post-operative treated brain metastasis with 86% with ≤ 4 lesions (median is 2, IQR is 3), 80% of the plans received single fraction and 43% of plans have a total PTV volumes of ≤ 1cc (median is 2.2cc and IQR is 7.5cc). We used a two tail T-test to check for correlation. The 50% relative dose gradient, R50%, was found to be dependent on PTV volume (P < 0.001), and a power law was used to fit the data. The brain volume, V12 Gy, was also found to be dependent on total PTV volume (P < 0.0001) and a linear curve was used to fit V12 Gy vs PTV. We did not find correlation between the number of lesions and R50% and or V12 Gy (p-value = 0.154 and 0.736, respectively). The dose gradient at 1cm away in any direction from PTV, %D1cm, has a median, average and a S.D. of 32%, 33% and 9%, respectively. 85% of all plans have %D1cm<42% which falls within 1 S.D. In addition, we found %D1cm to be dependent on both PTV volume and number of lesions (P < 0.001 for both). The modulation factor (MF) has a median, average and a S.D. of 2.9, 3.0 and 1.5, respectively. We found that 81% of all plans has MF < 4.5, which is within the 1 S.D. It has a positive correlation of 0.628 with the number of lesions.

CONCLUSION

We found a clear correlation between the total PTV volumes and R50% and V12 Gy, and a fit line was used to relate each parameter to the total PTV volume. As for %D1cm and MF, we found that the average value within 1 S.D. is adequate to include > 80% of the plan. We propose these four parameters to fill the gap for plan quality for Linac-based SRS and SRT. Further evaluation and validation of our results on larger cohort is needed to allow generalizability and applicability of the results and correlation with clinical outcomes to guide clinical decision making.

Evolving practice in global healthcare: Remote physics support for low- and middle-income countries

The COVID-19 pandemic has disrupted traditional onsite support for radiotherapy clinics in low- and middle-income countries (LMIC). Clinics there have struggled to commission new techniques and receive onsite training for their staff. We sought to evaluate whether an offsite approach could fill this gap at a clinic in Jordan by requesting a clinical audit and attempting to commission volumetric modulated arc therapy (VMAT). Over 13 months, a consultant provided remote support for a radiotherapy center that had already obtained treatment equipment and licenses. The consultant began by conducting a virtual audit, using a remote login to the center's R&V and TPS, to identify any gaps in the clinical workflow. Suggestions for improving the clinical workflow were proposed, and change implementation was tracked through emails, social media apps, and video conferencing. An extensive table outlined the commissioning process, including all measurements to be done. Social media apps and shared documents were used to track measurements and analysis. The lack of person-to-person interaction in this new remote-support ecosystem created conflicts; we have highlighted some of these, as well as their resolution and the lessons learned from them. The virtual audit identified gaps categorized as machine QA, treatment plan review, and treatment delivery processes. Following the implementation of the proposals, motion management was added, and machine QA became more comprehensive. VMAT was commissioned using the reports of the AAPM and the IAEA. The main challenges for remote support were time difference, establishing an appropriate form and frequency of communication, tone of voice used in messages, and buy-in from local staff. This evolving practice will enable medical physicists to use modern, multimodal remote communication pathways to effectively transfer knowledge to centers in LMICs. The audit-proposal-improvement pathway for remote support can be incorporated to help others while avoiding the pitfalls we faced.

Abstract 109: A Longitudinal Telehealth Curriculum for Radiation Oncology Centers in Low and Middle-Income Countries Transitioning from 2D to 3D External Beam Radiation Therapy

Purpose: The transition from 2-dimensional (2D) to 3-dimensional (3D) external beam radiation therapy (EBRT) can dramatically improve the quality of radiotherapy in low and middle-income countries (LMICs); however, many cancer centers in LMICs lack training support to effectively make this transition. Remote training is a low-cost, accessible option to bridge this gap, and we sought to evaluate the efficacy of such a program.

Methods: The nonprofit Rayos Contra Cancer identified 9 LMIC operational cancer centers in the Middle East and Northern Africa that had recently acquired technology to transition from 2D to 3D EBRT. Baseline information for each center was collected electronically, then a team of EBRT content experts developed a 12-week, 25-session continuing medical education curriculum. Each session invited live participation using Zoom video communications and lasted 1 - 2 hours. Participants were administered a Likert scale (1-5) confidence evaluation on 13 foundational topics in 3D EBRT and a 49-point knowledge-based multiple-choice examination pre- and post- curriculum. Anonymous feedback with 1-5 satisfaction scores for each session was solicited midway and at the conclusion of the curriculum. Training was provided for free.

Results: Among centers, 260 participants enrolled in training, including 39 medical physicists, 36 radiation oncologists, 54 radiation therapists, 15 dosimetrists, and 116 in training or other roles. Pre- and post-curriculum average examination scores were 22.95/49 (53.4%, N = 171) and 30.76/49 (62.8%, N=87), respectively. Pre- and post-curriculum confidence evaluation showed an average of 1.4/5 (27.7%, N=260) and 3.86 (77.2%, N=74) confidence among 13 topics. Satisfaction surveys (halfway N=51, end N=48) showed high satisfaction with helpfulness (4.3/5) enjoyableness (4.2/5), and well-preparedness (4.4/5) of sessions.

Conclusion: Satisfaction, confidence, and knowledge domains were all measured with favorable results. This innovative low-cost telehealth model for EBRT training is a promising vehicle for advancing cancer care in LMICs by providing educational support.

Citation Format: Fei Yang, Raymond Carter, Soha Ahmed, Tia Plautz, Piotr Dubrowski, Shada Wadi-Ramahi, Sarah Ashmeg, Frank Ascoli, Daniel Wakefield, Justus Adamson, Benjamin Li. A Longitudinal Telehealth Curriculum for Radiation Oncology Centers in Low and Middle-Income Countries Transitioning from 2D to 3D External Beam Radiation Therapy [abstract]. In: Proceedings of the 9th Annual Symposium on Global Cancer Research; Global Cancer Research and Control: Looking Back and Charting a Path Forward; 2021 Mar 10-11. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2021;30(7 Suppl):Abstract nr 109.

Successful Development of a Competency-Based Residency Training Program in Radiation Oncology: Our 15-Year Experience from Within a Developing Country

One of the main challenges of delivering high quality of care to cancer patients in developing countries is the lack of well-trained radiation oncologists. This is a direct cause for the lack of residency programs coupled with lack of resources. This article describes and details establishments of a successful and sustainable radiation-oncology residency program in our country. The program has been in operation for 14 years and has trained and graduated radiation oncologists who are now working in various countries. The curriculum of the 4-year residency program, fashioned according to American College of Radiologists (ACR) recommendations, includes site-specific clinical rotations and didactic lectures in clinical oncology, radiobiology, medical physics, statistics, and epidemiology. It also includes a component of advanced clinical experience in the form of 3-month externship at one of collaborating centers outside the country. Evaluation of the residents is conducted annually via written exams and 360° feedback. Residents also sit for the formal certification exam in radiation oncology from the national Medical Council. The exam consists of 2 written exams and one oral. As a form of benchmarking residents' knowledge, they are required to sit for the ACR examinations held annually and conducted in Amman in tandem. The program has successfully trained and graduated 28 residents, who now work as consultant radiation oncologists locally and abroad. Each resident has gone through a structured training that includes exposure to a Western-style patient-management culture, enhancing the breadth and width of their clinical experience. The residency program, initiated in a developing country, underwent many challenges, yet it overcome all obstacles and resulted in a successful training of competent radiation oncologists serving the region.

Board-certified specialty training program in radiation oncology in a war-torn country: Challenges, solutions and outcomes

BACKGROUND

Residency programs leading to board certification are important for safe and competent Radiation Oncology (RO) practice. In some developing nations, there is a gap in this field. This work addresses the experience that was accomplished to establish such a program in Iraq despite all the challenges that faces a country under war.

METHODS

Descriptive report of challenges faced in a developing country that is still reeling from war, the steps taken to overcome these challenges and outcomes after graduation of two classes.

RESULTS

After over 18 months of prerequisite technical and logistical preparations, a group of local and external faculty members were invited to establish the required syllabus of a structured RO residency program in Iraq. It is comprised of a total of 100 post-graduate academic credits over a 48-months period after clinical internship. First year evaluations included regular practical assessments; seven in-house papers covering RO, cancer and radiation biology, medical physics, radiological anatomy and diagnostic oncology, tumor pathology, onco-pharmacology, and medical statistics, research methodology, and cancer epidemiology, followed by a comprehensive examination. Subsequent evaluations were on an annual bases with enrollment in the American College of Radiology In-Training examination in RO. Final assessment included logbook and skills' reviews, graduation thesis or peer-review publication, two-papers' written examination, and an exit practical examination.

CONCLUSIONS

Given the political, economic and social difficulties in post-war Iraq, it was a major challenge to establish a residency program in RO. Despite the significant difficulties, the first residency program leading to board certification in RO was successfully started in Iraq. The new specialists will help in addressing the shortage of radiation oncologists in the country.

Practical steps for establishing ocular plaque therapy in developing countries

INTRODUCTION

Retinoblastoma and uveal melanoma are the most common ocular tumors in children and adults, respectively. Enucleation and external beam radiation therapy are integral in the management of ocular tumors. However, these tumors could also be treated effectively by plaque therapy, which has the potential of preserving the globe and maintaining vision.

METHODS AND MATERIALS

We reviewed our experience with the introduction of this technique to our center. Furthermore, we highlighted the critical role of a specialized multidisciplinary team in the successful implementation of this procedure.

DISCUSSION

This review represents a detailed report addressing the practical steps for successfully establishing plaque therapy in developing countries.

RESULTS

Plaque therapy was successfully implemented at our center in 1.5 years. Integration with an advanced cancer center is crucial for the correct transfer of this complex technology.

CONCLUSION

Complex brachytherapy procedures could be successfully established and implemented in developing countries.