Development of a United States Radiation Oncology Curricular Framework: A Stakeholder Delphi Consensus

PURPOSE

A United States (US) radiation oncology curriculum, developed using best practices for curriculum inquiry, is needed to guide residency education and qualifying examinations. Competency-based training, including entrustable professional activities (EPAs), provides an outcomes-based approach to modern graduate medical education. This study aimed to define US radiation oncology EPAs and curricular content domains using a deliberative process with input from multiple stakeholder groups.

METHODS AND MATERIALS

The Radiation Oncology Education Collaborative Study Group Core Curriculum Project Leadership Committee developed initial content domains and EPAs. Following recruitment of stakeholders, a Delphi process was used to achieve consensus. In the first round, content domains and EPAs were reviewed for inclusion and exclusion, clarity, time allocation (content domains), and level of training (EPAs). Participants submitted additional content domains and EPAs for consideration. Any content domains or EPAs 1 standard deviation below the median for inclusion and exclusion underwent Leadership Committee review. All participants completing the first Delphi round were invited to the second round. Percent curriculum time allocated for content domains and a single subdomain were finalized. New EPAs or EPAs undergoing major revisions were reviewed.

RESULTS

A total of 186 participants representing diverse stakeholder groups participated. One hundred fourteen completed the first Delphi round (61.3%). Of 114 invited, 77 participants completed the second round of the Delphi process (67.5%). Overall, 6 of 9 content domains met consensus, 1 content domain was removed, and 2 content domains were combined. Four subdomains of a single content domain were reviewed and met consensus. Consensus on percent time allocated per content domain and subdomain was reached. Of 55 initial EPAs, 52 final EPAs met consensus.

CONCLUSIONS

Deliberative curriculum inquiry was successfully used to develop a consensus on US radiation oncology content domains and EPAs. These data can guide the allocation of educational time in training programs, help inform weighting for qualifying examinations, and help guide clinical training and resident assessment.

The American Society for Radiation Oncology Workforce Taskforce Review of the United States Radiation Oncology Workforce Analysis

Over the past decade, concerns have arisen in radiation oncology regarding potential workforce supply and demand imbalance. The American Society for Radiation Oncology commissioned an independent analysis in 2022, looking at supply and demand in the United States radiation oncology workforce and projecting future trends for 2025 and 2030. The final report entitled, "Projected Supply and Demand for Radiation Oncologists in the U.S. in 2025 and 2030" is now available. The analysis included evaluating radiation oncologist supply (new graduates, exits from the specialty), potential changes in demand (growth of Medicare beneficiaries, hypofractionation, loss of indications, new indications) as well as radiation oncologist productivity (growth of work RVUs produced) and demand per beneficiary. The results demonstrated a relative balance between radiation oncology supply and demand for radiation services; the growth in radiation oncologists was balanced by the rapid growth of Medicare beneficiaries over the same time period. The primary factors driving the model were found to be growth of Medicare beneficiaries, and change in work RVU productivity with hypofractionation and loss of indication having only a moderate impact; while the most likely scenario was a balance of workforce supply and demand, scenarios did demonstrate the possibility of over and under supply. Oversupply may become a concern if radiation oncologist wRVU productivity reaches the highest region; beyond 2030, this is also possible if growth in radiation oncologist supply does not parallel Medicare beneficiary growth. Limitations of the analysis included the lack of inclusion of most technical reimbursement and its impact as well as failing to account for SBRT. A modeling tool is available to allow individuals to evaluate different scenarios. Moving forward, continued study will be needed to evaluate trends (particularly work RVU productivity and Medicare beneficiary growth) to allow for continued assessment of workforce supply and demand in radiation oncology.

Development and inter-institutional validation of an automatic vertebral-body misalignment error detector for Cone-Beam CT guided radiotherapy

BACKGROUND

In Cone-Beam Computed Tomography (CBCT) guided radiotherapy, off-by-one vertebral body misalignments are rare but serious errors which lead to wrong-site treatments.

PURPOSE

An automatic error detection algorithm was developed that uses a three-branch convolutional neural network error detection model (EDM) to detect off-by-one vertebral body misalignments using planning computed tomography (CT) images and setup CBCT images.

METHODS

Algorithm training and test data consisted of planning CTs and CBCTs from 480 patients undergoing radiotherapy treatment in the thoracic and abdominal regions at two radiotherapy clinics. The clinically applied registration was used to derive true-negative (no error) data. The setup and planning images were then misaligned by one vertebral body in both the superior and inferior directions, simulating the most likely misalignment scenarios. For each of the aligned and misaligned 3D image pairs, 2D slice pairs were automatically extracted in each anatomical plane about a point within the vertebral column. The three slice pairs obtained were then inputted to the EDM which returned a probability of vertebral misalignment. One model (EDM₁ ) was trained solely on data from institution #1. EDM₁ was further trained using a lower learning rate on a dataset from institution #2 to produce a fine-tuned model, EDM₂ . Another model, EDM₃ , was trained from scratch using a training dataset composed of data from both institutions. These three models were validated on a randomly selected and unseen dataset composed of images from both institutions, for a total of 303 image pairs. The model performances were quantified using a receiver operating characteristic analysis. Due to the rarity of vertebral body misalignments in the clinic, a minimum threshold value yielding a specificity of at least 99% was selected. Using this threshold, the sensitivity was calculated for each model, on each institution's test set separately.

RESULTS

When applied to the combined test set, EDM₁ , EDM₂ , and EDM₃ resulted in an area under curve of 99.5%, 99.4% and 99.5%, respectively. EDM₁ achieved a sensitivity of 96% and 88% on Institution #1 and Institution #2 test set, respectively. EDM₂ obtained a sensitivity of 95% on each institution's test set. EDM₃ achieved a sensitivity of 95% and 88% on Institution #1 and Institution #2 test set, respectively.

CONCLUSION

The proposed algorithm demonstrated accuracy in identifying off-by-one vertebral body misalignments in CBCT-guided radiotherapy that was sufficiently high to allow for practical implementation. It was found that fine-tuning the model on a multi-facility dataset can further enhance the generalizability of the algorithm. This article is protected by copyright. All rights reserved.

Evaluation of Radiation Oncologist And Trainee Opinions on Residency Expansion, Possible Actions, and Training Program Accreditation Changes in the United States

PURPOSE

To sample U.S. radiation oncologist and trainee opinions regarding residency expansion, what action(s) should be taken to limit residency supply, if any, and the proposed Accreditation Council for Graduate Medical Education (ACGME) changes.

MATERIALS AND METHODS

An online survey was distributed to 1048 attending radiation oncologists by email and ∼800 residents through their program coordinators. The survey asked respondents to rank how strongly they agreed with certain statements regarding residency supply, possible solutions to address any perceived oversupply, and the proposed ACGME changes on a 1-10 disagreement-to-agreement scale. The 16% response rate yielded 294 responses for analysis.

RESULTS

Of the respondents, 90 (30%) were residents, and 204 (70%) were attendings, of whom 117 (57%) were academic, and 87 (43%) were non-academic. 86% agreed that there is a residency oversupply issue, and 91% agreed that actions should be taken to limit residency expansion. On chi-square test, residents and attendings were similarly likely to agree that there is a residency oversupply issue (93% and 89%, p=0.27), although residents were more likely to agree that this oversupply should be acted upon compared to attendings (100% and 88%, p<0.01). Regarding possible solutions, respondents were most likely to agree that further expansion should be limited (90%), program requirements should be made more stringent (76%), and the use of the Supplemental Offer and Acceptance Program should be limited (SOAP) (69%). Proposed ACGME changes that respondents were most likely to agree with included requiring that programs have modern image guidance, stereotactic radiotherapy, and brachytherapy techniques (98%) and have 4+ faculty members and maintain a faculty-to-resident ratio of >1.5:1 (86%). Case log minimums most supported to be increased were 4 uterus (65%) and 11 postmastectomy breast (61%) simulations.

CONCLUSIONS

The majority of respondents agree that there is a residency oversupply issue and that actions should be taken to limit residency expansion and make program requirements more stringent.

Inter-fractional variation of markers and applicators in single-implant high-dose-rate interstitial brachytherapy for gynecologic malignancies

PURPOSE

Implanted fiducial markers are a commonly used tool in delineating the CTV in high-dose-rate interstitial brachytherapy (HDR-ISBT) for gynecologic malignancy, but their reliability in gynacological sites is not well understood. These markers and interstitial applicators can experience interfractional motion due to organ swelling or other anatomical changes. The purpose of this study was to evaluate the spatial variation of these features.

METHODS AND MATERIALS

The spatial positions of 50 implanted markers and 202 needles were tracked in 15 patients treated over 70 fractions of HDR brachytherapy. Marker and/or needle coordinates were extracted from CT images with contours and dose distributions. Automated analysis determined marker self-consistency and displacements between various elements of the implant.

RESULTS

From start to end fraction, the relative positions of the markers experienced an average magnitude displacement of 4.5 ± 3.0 mm while the average displacement of the applicator tips was 11 ± 8 mm, relative to their respective centers of mass (CM).

CONCLUSIONS

Markers implanted lateral and superior to the CTV experience greater drift than other implant locations.

Feasibility of deploying a U.S. simulation-based gynecological brachytherapy educational workshop to an international setting

PURPOSE

A decline in brachytherapy (BT) use for cervical cancer has negatively affected cure rates in the United States and abroad. To improve trainee exposure to BT, a simulation-based educational curriculum incorporating a pelvic mannequin was developed and implemented at several U.S. residency programs. We sought to describe an initial experience with deployment of this curriculum to an international setting.

METHODS AND MATERIALS

The setting was in Israel, a middle eastern country with cervical cancer incidence of 5-8 cases per 100,000 women. Israel was selected for this pilot because of its desire to increase exposure to trainees, lack of mandatory BT case requirements, and few residencies nationally. In determining the feasibility of deployment to this setting, a partnership was formed between a U.S. and Israeli brachytherapist to understand cultural context and institutional and logistical needs. Feasibility was defined as successful completion of the workshop. Trainee comfort and knowledge with BT was assessed with preworkshop and postworkshop surveys, with changes compared.

RESULTS

The curriculum was incorporated into a 1-day course on gynecologic malignancies, with adaptation to local setting and routine. Among 15 attendees, eight were residents, from four programs. All completed the workshop. All domains assessed by the surveys improved and all respondents found the program to be helpful.

CONCLUSIONS

International deployment of the simulation-based educational BT curriculum was feasible and well-received. Further collaboration is needed to deploy and adapt the curriculum to countries of high cervical cancer incidence that could benefit from increased education.

COVID-19 impact on timing of brachytherapy treatment and strategies for risk mitigation

PURPOSE

The purpose of this study was to highlight the importance of timely brachytherapy treatment for patients with gynecologic, breast, and prostate malignancies, and provide a framework for brachytherapy clinical practice and management in response to the COVID-19 pandemic.

METHODS AND MATERIALS

We review amassing evidence to help guide the management and timing of brachytherapy for gynecologic, breast, and prostate cancers. Where concrete data could not be found, peer-reviewed expert opinion is provided.

RESULTS

There may be a significant negative impact on oncologic outcomes for patients with gynecologic malignancies who have a delay in the timely completion of therapy. Delay of prostate or breast cancer treatment may also impact oncologic outcomes. If a treatment delay is expected, endocrine therapy may be an appropriate temporizing measure before delivery of radiation therapy. The use of shorter brachytherapy fractionation schedules will help minimize patient exposure and conserve resources.

CONCLUSIONS

Brachytherapy remains a critical treatment for patients and may shorten treatment time and exposure for some. Reduced patient exposure and resource utilization is important during COVID-19. Every effort should be made to ensure timely brachytherapy delivery for patients with gynecologic malignancies, and endocrine therapy may help temporize treatment delays for breast and prostate cancer patients. Physicians should continue to follow developing institutional, state, and federal guidelines/recommendations as challenges in delivering care during COVID-19 will continue to evolve.

U.S. experience with the AddVent VDD(R) pacing system. AddVent Phase I Investigators

The AddVent pacemaker generator and model 1328C AV single-pass lead is a new pacemaker system capable of VDD or VDDR modes. The purpose of this study was to present the initial experience with AddVent in the United States and Canada. Between May 10, 1995 and May 3, 1996, 53 devices were implanted in 52 patients and followed for a mean of 217 (+/- 39) days. At the predischarge, 1-, 3-, and 6-month follow-up evaluations, atrial sensing thresholds and ventricular sensing and capture thresholds were measured in the supine, sitting, and standing positions to evaluate stability of atrial sensing with respect to body posture at rest. At the 1-month follow-up, a treadmill exercise test was performed to evaluate atrial sensing during exercise and to evaluate two new features of the AddVent called "sensor-mediated rate smoothing" and "preferential P wave sensing." Atrial sensing thresholds were not significantly different (P > 0.05) among body postures for any follow-up period or among follow-up periods for each posture. At rest, the percentage of appropriately tracked P waves observed was > 99% at each follow-up period. During treadmill exercise, the percentage of appropriately tracked P waves was > 98.7%. Appropriate preferential P wave sensing and sensor-mediated rate smoothing (VDDR mode) was observed. The AddVent pacing system provides safe and effective pacing therapy. Several features of VDDR pacing offer advantages over standard VDD pacing.