Laughlin, Brady S

Healthcare Systems Science (HSS) is an important part of medical education because it helps physicians understand how healthcare systems work and how to improve them. However, it is not commonly included in graduate medical training. This manuscript describes the creation and use of a radiation oncology (RO) HSS curriculum that was built with medical school faculty and adapted to the needs of residents in our residency program. The curriculum included sixteen sessions over ten months and covered six domains: person centered care, population centered care, team-based care, high value care, leadership, and health policy economics and technology. Each session included a short lecture and a case discussion on topics such as financial toxicity, telemedicine, workflow improvement, burnout, health equity, and billing. The curriculum was used successfully with regular participation from residents and faculty, showing that it can fit into an existing residency schedule. Residents completed pre- and post-intervention surveys assessing understanding, consideration, confidence, and satisfaction related to HSS domains using 5-point Likert-scale items. Among residents with paired survey data, scores for understanding of HSS, incorporation of HSS into care planning, confidence applying HSS principles, and satisfaction with HSS integration all improved following curriculum completion. This experience shows that adding HSS to RO residency training is practical and useful, and it may also be a helpful model for other residency programs.

Purpose To implement and evaluate a faculty mentorship skill development curriculum within a radiation oncology department at a single academic medical center. Methods A three-part faculty development curriculum consisting of three 45-minute facilitated workshops was implemented for physician faculty mentors. The curriculum was designed to support mentors in navigating mentoring relationships, aligning expectations, and fostering mentee independence. Content was informed by evidence-based mentorship frameworks and adult learning principles, including models developed by the Center for the Improvement of Mentored Experiences in Research, social cognitive theory, and principles of psychological safety and self-efficacy. Faculty participants representing a range of academic ranks and mentoring experience levels participated voluntarily. Pre- and post-curriculum self-assessment surveys evaluated participant understanding and implementation of mentorship skills, as well as perceptions of common mentorship challenges, using a 5-point Likert scale (1 = strongly disagree to 5 = strongly agree). Descriptive statistics were used to analyze responses. Results Curriculum content progressed from foundational mentorship concepts, including mentor roles, mentoring networks, and stages of mentoring relationships, to communication strategies, expectation alignment, and promotion of mentee independence. Educational methods included brief didactic instruction, case-based discussion, guided reflection, and peer-to-peer learning. Survey data demonstrated improvement in participant self-assessment scores across all evaluated mentorship domains, including mentoring across differences, supporting mentee goal achievement, confidence as a mentor, providing constructive feedback, awareness of mentorship challenges, setting clear expectations, and understanding core mentorship competencies. Participants also reported reduced perceived challenges related to mentorship, with the largest improvements observed in setting boundaries, mentoring across differences, and addressing sensitive topics. Conclusions This faculty mentorship development curriculum was feasible to implement and demonstrated favorable early improvements in self-reported mentorship knowledge, confidence, and perceived ability to navigate common mentorship challenges. Further longitudinal evaluation is needed to assess sustained implementation of mentorship skills and longer-term impact on mentoring relationships.

In this study, we investigated whether radiomics features from pre-treatment positron emission tomography (PET) images could be used to predict disease progression in patients with HPV-positive oropharyngeal cancer treated with definitive proton or x-ray radiotherapy. Machine learning models were built using a dataset from Mayo Clinic, Rochester, Minnesota (n = 72) and tested on a dataset from Mayo Clinic, Phoenix, Arizona (n = 22). A total of 71 clinical and radiomics features were considered. The Mann–Whitney U test was used to identify the top 2 clinical and top 20 radiomics features that were significantly different between progression and progression-free patients. Two dimensionality reduction methods were used to define two feature sets (manually filtered or machine-driven). A forward feature selection scheme was conducted on each feature set to build models of increased complexity (number of input features from 1 to 6) and evaluate model robustness and overfitting. The machine-driven features had superior performance and were less prone to overfitting compared to the manually filtered features. The four-variable Gaussian Naïve Bayes model using the ‘Radiation Type’ clinical feature and three machine-driven features achieved a training accuracy of 79% and testing accuracy of 77%. These results demonstrate that radiomics features can provide risk stratification beyond HPV-status to formulate individualized treatment and follow-up strategies.

Purpose: Planning target volume (PTV) expansion for post-prostatectomy radiotherapy is typically ≥5 mm. Recent clinical trials have proved the feasibility of a reduced margin of 2–3 mm for treatments on MRI-linac. We aim to study the minimum PTV margin needed using iterative cone-beam CT (iCBCT) as image guidance on conventional linacs. Materials/Methods: Fourteen patients who received post-prostatectomy irradiation (8 with an endorectal balloon and 6 without a balloon) were included in this study. Treatment was delivered with volumetric modulated radiation therapy (VMAT). Fractional dose delivery was evaluated in 165 treatment fractions. The bladder, rectal wall, femoral heads, and prostate bed clinical tumor volume (CTV) were contoured and verified on daily iCBCT. PTV margins (0 mm, 2 mm, and 4 mm) were evaluated on daily iCBCT. CTV coverage and OAR dose parameters were assessed with each PTV margin. Results: CTV D100% was underdosed with a 0 mm margin in 32% of fractions in comparison with 2 mm (6%) and 4 mm (6%) PTV margin (p ≤ 0.001). CTV D95% > 95% was met in 93–94% fractions for all PTV expansions. CTV D95% > 95% was achieved in more patients with an endorectal balloon than those without: 0 mm—90/91 (99%) vs. 63/74 (85%); 2 mm—90/91 (99%) vs. 65/75 (87%); 4 mm—90/90 (100%) vs. 63/73 (86%). There was no difference in absolute median change in CTV D95% (0.32%) for 0-, 2-, and 4 mm margins. The maximum dose remained under 108% for 100% (0 mm), 97% (2 mm), and 98% (4 mm) of images. Rectal wall maximum dose remained under 108% for 100% (0 mm), 100% (2 mm), and 98% (4 mm) of images. Conclusions: With high-quality iCBCT image guidance, PTV margin accounting for inter-fractional uncertainties can be safely reduced for post-prostatectomy radiotherapy. For fractionated radiotherapy, an isotropic expansion of 2 mm and 4 mm may be considered for margin expansion with and without the endorectal balloon. Future application for margin reduction needs to be further evaluated and considered with the advent of shorter post-prostatectomy radiation courses.

Purpose: Post-operative prostate cancer patients are treated with full bladder instruction and the use of an endorectal balloon (ERB). We reassessed the efficacy of this practice based on daily image guidance and dose delivery using high-quality iterative reconstructed cone-beam CT (iCBCT). Methods: Fractional dose delivery was calculated on daily iCBCT for 314 fractions from 14 post-operative prostate patients (8 with and 6 without ERB) treated with volumetric modulated radiotherapy (VMAT). All patients were positioned using novel iCBCT during image guidance. The bladder, rectal wall, femoral heads, and prostate bed clinical tumor volume (CTV) were contoured and verified on daily iCBCT. The dose-volume parameters of the contoured organs at risk (OAR) and CTV coverage were assessed for the clinical impact of daily bladder volume variations and the use of ERB. Minimum bladder volume was studied, and a straightforward bladder instruction was explored for easy clinical adoption. Results: A “minimum bladder” contour, the overlap between the original bladder contour and a 15 mm anterior and superior expansion from prostate bed PTV, was confirmed to be effective in identifying cases that might fail a bladder constraint of V65% <60%. The average difference between the maximum and minimum bladder volumes for each patient was 277.1 mL. The daily bladder volumes varied from 62.4 to 590.7 mL and ranged from 29 to 286% of the corresponding planning bladder volume. The bladder constraint of V65% <60% was met in almost all fractions (98%). CTVs (D90%, D95%, and D98%) remained well-covered regardless of the absolute bladder volume daily variation or the presence of the endorectal balloon. Patients with an endorectal balloon showed smaller variation but a higher average maximum rectal wall dose (D0.03mL: 104.3% of the prescription) compared to patients without (103.3%). Conclusions: A “minimum bladder” contour was determined that can be easily generated and followed to ensure sufficient bladder sparing. Further analysis and validation are needed to confirm the utility of the minimal bladder contour. Accurate dose delivery can be achieved for prostate bed target coverage and OAR sparing with or without the use of ERB.

AbstractBackgroundIn patients with extremity soft tissue sarcoma (eSTS), we describe outcomes of preoperative external beam radiation therapy (EBRT), limb‐sparing surgery (LSS), and intraoperative electron radiation therapy (IOERT).MethodsOne hundred and eighteen patients with eSTS treated between October 17, 2002 and July 28, 2021 were identified. EBRT was delivered preoperatively followed by LSS and IOERT.ResultsThe median follow‐up was 24.9 months. The presentation was primary in 102 (94%) patients and recurrent in 6 (6%) patients. Tumor location was lower extremity in 82 (76%) patients and upper extremity in 26 (24%) patients. Stage distribution was as follows: 3 (3%) IA, 24 (22%) IB, 31 (29%) II, 24 (22%) IIIA, and 25 (23%) IIIB. Final surgical margins were negative in 96 (89%) patients. The 5‐year local control, failure‐free survival, and overall survival were 94%, 75%, and 64%, respectively. Univariate analysis identified age >50, lower extremity, and higher grade as significant negative prognostic factors for overall survival. Grade 3 fracture or osteoradionecrosis requiring surgical fixation, neuropathy, and lymphedema occurred in 7 (6%), 1 (1%), and 0 patients, respectively.ConclusionsThis study represents one of the largest series using preoperative EBRT, LSS, and IOERT for eSTS, with high local control and a low rate of late severe toxicity.

AbstractPurpose/ObjectivesHolmium laser enucleation of the prostate (HoLEP) is commonly performed in patients with significant bladder outlet obstruction. However, there are few reports on the toxicity of external beam irradiation (RT) for prostate cancer in patients after prior HoLEP. In this study, we evaluate the side effects and treatment outcomes of RT after HoLEP.Materials/MethodsEighteen patients who had HoLEP and subsequently received RT for prostate cancer were included. Data collected included patient and disease characteristics, urinary function, and radiation dose. Acute and late urinary (GU) and gastrointestinal (GI) side effects were evaluated. Disease control and survival rates were calculated using Kaplan–Meier method.ResultsMedian follow‐up was 18 months (range: 4–46 months). Median prostate volume was 107 ml before HoLEP and 24 ml after HoLEP. Median International Prostate Symptom Score (IPSS) was 17 (range: 5–32) before HoLEP. Median decline in IPSS score after HoLEP was 7 (range: −2–21). On uroflow study, peak flow rate, and post‐void residual were significantly improved after HoLEP. After radiation, peak flow rate and average flow rate showed a decline but remained significantly improved compared to pre‐HoLEP measurements. Maximum acute Common Terminology Criteria for Adverse Events (CTCAE) adverse events were 12 grade 1 and 3 grade 2 for GU, and 3 grade 1 for GI, respectively. Maximum late adverse events were 13 grade 1 and 2 grade 2 for GU, and all grade 0 for GI, respectively. At last follow‐up, there were 8 grade 1 and 1 grade 2 late GU, and 3 grade 1 late GI adverse events, respectively. There was no significant increase in urinary incontinence after RT compared to before RT. The 18‐month biochemical control, local control, distant control rates were 78%, 94%, and 80%, respectively.ConclusionsPatients who received RT as definitive treatment for prostate cancer after prior HoLEP had low risk of serious acute and late side effects. HoLEP can be safely performed and should be considered in patients with significant bladder outlet obstruction and large prostate volume before RT.