Purpose: This study aimed to generate a map of local recurrences after neoadjuvant chemotherapy and radiation (total neoadjuvant therapy [TNT]) followed by surgical resection for pancreatic ductal adenocarcinoma (PDAC). Such recurrence patterns will serve to inform radiation treatment planning volumes that should be given in the neoadjuvant setting. Methods and Materials: Locoregional recurrences after TNT followed by surgery treated between 2009 and 2022 were radiologically identified. Recurrences were individually segmented using MIM software and complied in a single base scan. All contour compilations were used to create a threshold contour encompassing 80% of recurrences among all patients, head only, and body/tail only. The distance between organs at risk and the threshold contour were measured to design an optimal clinical target volume contour for patients treated with TNT. Recurrence patterns were also compared with existing adjuvant guidelines to assess coverage. Results: A database of 474 patients managed with TNT for PDAC was queried. While locoregional recurrences were rare in this cohort, we identified 80 patients with either isolated locoregional or simultaneous local and distant recurrences. Patients with diagnostic imaging at the time of recurrence were identified. The majority of recurrences were partially in the field of published contouring guidelines or volumetric expansions off of vessels, and volumetric coverage was low for all. Common areas of recurrence include the aorticodiaphragmatic junction, retropancreatic duodenal nodal basin, and the region to the right of the superior mesenteric artery. A novel set of proposed neoadjuvant contours was designed to cover the central-most 80% of recurrences. Conclusions: This is the largest collection of local/regional PDAC recurrences from a cohort of patients treated exclusively with TNT. Patterns of local/regional recurrence using TNT in PDAC vary significantly from those patients with PDAC treated with a surgery-first approach. Novel contouring guidelines presented in this study can help to ensure optimal coverage of high risk regions and avoid reliance on the current adjuvant guidelines to guide treatment planning. Published by Elsevier Inc. on behalf of American Society for Radiation Oncology.

Purpose: We sent surveys to a large number of radiation oncologists with active thoracic cancer practices and applied the Delphi method over 3 rounds to generate consensus dose-volume histogram metrics. We used these results to create consensus-based organsat-risk dose constraints and target goal templates for practical implementation. Methods and Materials: In this institutional review board-approved study, data were collected using REDCap electronic data capture on a secure server. Radiation oncologists identified from the Accreditation Council for Graduate Medical Education-accredited departments' websites were asked to confirm their self-identification as thoracic radiation oncologists and nominate other respondents. All invitees were asked to complete 3 rounds of questions related to normal tissue constraints, target coverage metrics, prescribing practices, and other planning considerations. Preliminary consensus statements were presented in the second round of surveys for voting on a 5point Likert scale. The third and last round of surveys presented the iterated consensus statements and target coverage metric statements Results: Eighty-three (42.8%) of 194 invitees completed at least 1 round of surveys. The group included a diversity of gender, geography, and clinical settings. Response rates were 83%, 57%, and 55%, respectively, for the 3 rounds. By the end of the process, 48 of 96 (50%) originally proposed normal tissue dose constraint statements were iterated to consensus, and 5 of 7 (71%) proposed target coverage metric statements achieved consensus. These were used to create crowdsourced treatment planning templates. Conclusion: This study achieved broad-based consensus-building on ideal and acceptable dose constraints for conventional, twicedaily, and stereotactic thoracic radiation therapy. Future directions could include extending this approach to other disease sites, studying the influence of widespread implementation on treatment planning, or facilitating the development of community consensus around emergent or controversial questions.

OBJECTIVES:This practice parameter was revised collaboratively by the American College of Radiology (ACR) and American Radium Society (ARS). Stereotactic body radiation therapy (SBRT) precisely delivers higher dose(s) of radiation in 5 of fewer fractions, compared with conventional radiation. Given the complexity and technical nature of this treatment technique, practice parameters are needed to provide guidance to physicians and physicists. METHODS:This practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS. RESULTS:Workflow, qualifications/responsibilities of personnel, quality control, and treatment delivery/verification are reviewed. Notable elements of SBRT include image guidance, immobilization, and motion management, with the treatment planning goal of minimizing the volume of normal tissue exposed to medium and high dose levels and maximizing dose safely to the target. Specialized training is encouraged, as some technologies are not used in standard treatments. CONCLUSIONS:This practice parameter provides direction on key components recommended for SBRT and may be used as a guide to physicians and physicists wanting to provide this treatment to their patients.

PURPOSE:To provide guidance on the recommended management of cancer in pregnant patients. METHODS:A multidisciplinary Expert Panel convened and conducted a systematic review of the literature. RESULTS:The systematic review identified 450 eligible studies. Much of the evidence consisted of observational data, case series, and case reports. RECOMMENDATIONS:Management of cancer during pregnancy should be grounded in a values-based informed-consent process outlining maternal and fetal risks and anticipated benefits. Diagnostic evaluation should follow the as low as reasonably achievable (ALARA) principle, with timing of diagnostic studies individualized based on urgency of cancer detection, potential dangers of delay, and the balance of risks to both the pregnant patient and her embryo or fetus. Due to significant risk of harm to the developing embryo and/or fetus, systemic therapy should be deferred until the second trimester. Methotrexate, hormonal therapies, human epidermal growth factor receptor 2-targeted agents, vascular endothelial growth factor and poly (ADP-ribose) polymerase inhibitors, antibody-drug conjugates, and all cellular therapies are contraindicated during pregnancy, regardless of gestational age. For patients who wish to continue their pregnancy, delivery should be planned at or after 37 weeks, with the final chemotherapy dose scheduled 2-4 weeks before birth. Referral to psychosocial support services is essential to address emotional and practical challenges, reduce distress, and support shared decision making.Additional information is available at www.asco.org/survivorship-guidelines.

The ARS brain committee recommends that vorasidenib may be appropriate for recurrent or residual IDH-mutant grade 2 oligodendroglioma or astrocytoma. Vorasidenib is usually not appropriate for completely resected grade 2 oligodendroglioma or astrocytoma, any grade 3 oligodendroglioma or astrocytoma, or combined with radiotherapy and/or chemotherapy for any grade 2-3 glioma.

Background:This practice parameter was revised collaboratively by the American College of Radiology (ACR), and the American Radium Society (ARS). Timely, accurate, and effective communications are critical to quality and safety in contemporary medical practices. Radiation oncology incorporates the science and technology of complex, integrated treatment delivery and the art of providing care to individual patients. Through written physical and/or electronic reports and direct communication, radiation oncologists convey their knowledge and evaluation regarding patient care, clinical workup, and treatment provided to others in the management of the patient. Applicable practice parameters need to be revised periodically regarding medical record documentation for professional and technical components of services delivered.Methods:This practice parameter was developed and revised according to the process described under the heading "The Process for Developing ACR Practice Parameters and Technical Standards" on the ACR website (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS. Both societies have reviewed and approved the document.Results:This practice parameter addresses radiation oncology communications in general, including (a) medical record, (b) electronic, and (c) doctor-patient communications, as well as specific documentation for radiation oncology reports such as (a) consultation, (b) clinical treatment management notes (including inpatient communication), (c) treatment (completion) summary, and (d) follow-up visits.Conclusions:The radiation oncologist's participation in the multidisciplinary management of patients is reflected in timely, medically appropriate, and informative communication with patients, caregivers, referring physician, and other members of the health care team. The ACR-ARS Practice Parameter for Communication: Radiation Oncology is an educational tool designed to assist practitioners in providing appropriate communication regarding radiation oncology care for patients.

PURPOSE:This study aims to compare the dosimetric impact of incorporating systematic and random setup uncertainties in the robust optimization of head and neck cancer (HNC) Intensity Modulated Proton Therapy (IMPT) plans. METHODS:Bilateral HNC patients (n = 10) previously treated with conventional photon therapy at our institution were included. Both systematic and random setup uncertainties were incorporated into the robust optimization process of IMPT planning. Dosimetric comparisons were made between plans optimized with systematic (IMPT-S) versus random (IMPT-R) setup uncertainties, assessing both the clinical target volume (CTVs) and organs at risk (OARs) across various dosimetric metrics. Both plans applied a fixed range uncertainty of ± 3 % and a maximum setup uncertainty of ± 3 mm. RESULTS:Both IMPT-S and IMPT-R plans achieved similar target coverage, meeting robustness criteria for CTVs. On average, the D95% voxel-wise min to the high-risk CTV (CTV_HR) was slightly higher in IMPT-S plans by 1.78 ± 0.72 % compared to IMPT-R plans. However, IMPT-R plans provided better OAR sparing, which was evident in both nominal and voxel-wise maximum values. While random setup errors in robust optimization improved OAR sparing, the clinical impact may be minimal where OAR doses are already well below tolerance levels. CONCLUSION:Both IMPT-S and IMPT-R techniques met the robustness criteria for CTVs in HNC IMPT planning. Incorporating random setup uncertainties in robust optimization improves OAR sparing compared to systematic setup uncertainties. Further research is needed to explore the broader applicability of random setup errors and to integrate random uncertainties in robustness evaluations for a more comprehensive assessment of treatment plans.

PURPOSE:Meningiomas are the most common primary intracranial tumor. Somatostatin receptor 2 is almost universally expressed in meningioma tissue. For patients who require adjuvant radiation, somatostatin receptor based (68)Ga-DOTATATE positron emission tomography (PET) imaging can detect additional or residual disease not discernible on magnetic resonance imaging. PET guided radiation treatments may improve local control, minimize toxicity by allowing for more precise radiation therapy plans, and allow for more precise dose-escalation to maximize local control. The aim of this study was to develop consensus PET guided treatment planning guidelines for common meningioma presentations. METHODS AND MATERIALS:Five postoperative clinically relevant meningioma cases were selected from a prospective single-institutional registry of patients. Each patient had a preoperative and postoperative contrast-enhanced T1-weighted volumetric magnetic resonance imaging, and a postoperative (68)Ga-DOTATATE PET/CT, to assist with target delineation. The full treatment scenario including clinical history, histology, surgical history, and imaging were provided for each patient. Nineteen international experts who have published on the treatment and management of meningiomas, and who use (68)Ga-DOTATATE PET/CT in their practice, evaluated each case. Individual prescription recommendations were created, pooled, and discussed to create consensus recommendations. RESULTS:Consensus recommendations were created for each case. In most cases, PET-based contouring allowed for more precise dose-escalation to 66-70 Gy targeting residual disease. When compared to RTOG 0539 and modern clinical trial contouring guidelines, a smaller clinical target volume expansion from the surgical cavity was recommended using PET guided radiation plans in the absence of radiographic or pathologic evidence of brain or bone invasion. CONCLUSIONS:This report provides consensus target volume delineation guidelines for meningiomas receiving postoperative radiation in common clinical situations. Integration of these guidelines into clinical practice may allow for more precise biomarker guided radiation treatments and standardize radiation therapy on future meningioma clinical trials.

PURPOSE:A novel proton beam delivery method known as DynamicARC spot scanning has been introduced. The current study aims to determine whether the partial proton arc technique, in conjunction with DynamicARC pencil beam scanning (PBS), can meet clinical acceptance criteria for bilateral head and neck cancer (HNC) and provide an alternative to full proton arc and traditional intensity-modulated proton therapy (IMPT). METHOD:The study retrospectively included anonymized CT datasets from ten patients with bilateral HNC, all of whom had previously received photon treatment. The clinical target volumes (CTV) were categorized into three levels: CTV_7000, CTV_5950, and CTV_5600. IMPT plans included three beams, whereas DynamicARC plans included dual-partial-arcs (DPA), single-partial-arc (SPA), and single-full-arc (SFA). All plans underwent robust optimization considering setup (± 3 mm) and range (± 3%) uncertainties applied to the CTVs. DynamicARC plans were evaluated against the NRG-HN009 criteria and IMPT plans using various metrics. RESULTS:All four techniques-IMPT, DPA, SPA, and SFA-demonstrated substantial compliance with NRG-HN009 dosimetric criteria. DynamicARC produced superior dose conformity, lower hotspot, and improved homogeneity for high-risk CTV compared to IMPT, with comparable performance for intermediate- and low-risk CTVs. DynamicARC reduced the Dmean to the parotid glands by average differences of 14.5%-22.1% and to the oral cavity by an average difference of 15.75% compared to IMPT. DPA and SPA techniques achieved reductions in total integral dose of 3.7%-5.7% relative to IMPT. Overall, DPA yielded dosimetric results comparable to those of SFA while offering more conformal dose distributions and slightly better organ at risk sparing than SPA. CONCLUSION:On the ProteusOne with a partial gantry system, DPA and SPA, in conjunction with DynamicARC PBS protons, provided clear dosimetric advantages over three-field IMPT. Future clinical implementation and further research into optimizing DynamicARC protocols are warranted to fully realize the benefits of these techniques in clinical settings.

Background: In current clinical practice, intensity-modulated proton therapy (IMPT) head and neck cancer (HNC) plans are generated using a constant relative biological effectiveness (cRBE) of 1.1. The primary goal of this study was to explore the dosimetric impact of proton range uncertainties on RBE-weighted dose (RWD) distributions using a variable RBE (vRBE) model in the context of bilateral HNC IMPT plans. Methods: The current study included the computed tomography (CT) datasets of ten bilateral HNC patients who had undergone photon therapy. Each patient’s plan was generated using three IMPT beams to deliver doses to the CTV_High and CTV_Low for doses of 70 Gy(RBE) and 54 Gy(RBE), respectively, in 35 fractions through a simultaneous integrated boost (SIB) technique. Each nominal plan calculated with a cRBE of 1.1 was subjected to the range uncertainties of ±3%. The McNamara vRBE model was used for RWD calculations. For each patient, the differences in dosimetric metrices between the RWD and nominal dose distributions were compared. Results: The constrictor muscles, oral cavity, parotids, larynx, thyroid, and esophagus showed average differences in mean dose (Dmean) values up to 6.91 Gy(RBE), indicating the impact of proton range uncertainties on RWD distributions. Similarly, the brachial plexus, brain, brainstem, spinal cord, and mandible showed varying degrees of the average differences in maximum dose (Dmax) values (2.78–10.75 Gy(RBE)). The Dmean and Dmax to the CTV from RWD distributions were within ±2% of the dosimetric results in nominal plans. Conclusion: The consistent trend of higher mean and maximum doses to the OARs with the McNamara vRBE model compared to cRBE model highlighted the need for consideration of proton range uncertainties while evaluating OAR doses in bilateral HNC IMPT plans.

Objectives: Consent is a communication process between the patient and a health care provider, in which both parties have the opportunity to ask questions and exchange information relevant to the patient’s diagnosis and treatment. The process of informed consent is designed to protect a patient’s autonomy in their medical decision-making in the context of an asymmetric relationship with the health care system. A proper consent process assures a patient’s individual autonomy, reduces the opportunity for abusive conduct or conflicts of interest, and raises trust levels among participants. This document was developed as an educational tool to facilitate these goals. Methods: This practice parameter was produced according to the process described under the heading “The Process for Developing ACR Practice Parameters and Technical Standards” on the ACR website (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters—Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS. Committee members were charged with reviewing the prior version of the informed consent practice parameter published in 2017 and recommending additions, modifications, or deletions. The committee met through remote access and subsequently through an online exchange to facilitate the development of the revised document. Focus was given on identifying new considerations and challenges with informed consent given the evolution of the practice of radiation oncology in part driven by the COVID-19 pandemic and other external factors. Results: A review of the practice parameter published in 2017 confirmed the ongoing relevance of recommendations made at that time. In addition, the evolution of the practice of radiation oncology since the publication of the prior document resulted in the need for new topics to be addressed. These topics include remote consent either through telehealth or telephone and with the patient or their health care proxy. Conclusions: Informed consent is an essential process in the care of radiation oncology patients. This practice parameter serves as an educational tool designed to assist practitioners in optimizing this process for the benefit of all involved parties.

PURPOSE:This joint guideline by American Society for Radiation Oncology (ASTRO) and the European Society for Radiotherapy and Oncology (ESTRO) was initiated to review evidence and provide recommendations regarding the use of local therapy in the management of extracranial oligometastatic non-small cell lung cancer (NSCLC). Local therapy is defined as the comprehensive treatment of all known cancer-primary tumor, regional nodal metastases, and metastases-with definitive intent.METHODS:ASTRO and ESTRO convened a task force to address 5 key questions focused on the use of local (radiation, surgery, other ablative methods) and systemic therapy in the management of oligometastatic NSCLC. The questions address clinical scenarios for using local therapy, sequencing and timing when integrating local with systemic therapies, radiation techniques critical for oligometastatic disease targeting and treatment delivery, and the role of local therapy for oligoprogression or recurrent disease. Recommendations were based on a systematic literature review and created using ASTRO guidelines methodology.RESULTS:Based on the lack of significant randomized phase 3 trials, a patient-centered, multidisciplinary approach was strongly recommended for all decision-making regarding potential treatment. Integration of definitive local therapy was only relevant if technically feasible and clinically safe to all disease sites, defined as 5 or fewer distinct sites. Conditional recommendations were given for definitive local therapies in synchronous, metachronous, oligopersistent, and oligoprogressive conditions for extracranial disease. Radiation and surgery were the only primary definitive local therapy modalities recommended for use in the management of patients with oligometastatic disease, with indications provided for choosing one over the other. Sequencing recommendations were provided for systemic and local therapy integration. Finally, multiple recommendations were provided for the optimal technical use of hypofractionated radiation or stereotactic body radiation therapy as definitive local therapy, including dose and fractionation.CONCLUSIONS:Presently, data regarding clinical benefits of local therapy on overall and other survival outcomes is still sparse for oligometastatic NSCLC. However, with rapidly evolving data being generated supporting local therapy in oligometastatic NSCLC, this guideline attempted to frame recommendations as a function of the quality of data available to make decisions in a multidisciplinary approach incorporating patient goals and tolerances.

11018 Background: Imposter syndrome (IS) is defined as an inability to believe that one’s success is deserved. It is commonly encountered by physicians, with cited statistics ranging from 22% to 98%, is associated with negative mental health impacts and can be harmful to one’s wellbeing. Given increasing SM use in hematology/oncology (H/O), we aimed to evaluate the effect of SM on IS among oncology trainees and oncologists. Methods: An anonymous online survey was distributed to oncology trainees and oncologists through SM platforms (Twitter, Facebook (FB), Instagram (IG)) and e-mail. Questions included demographics, current SM use, a novel scale for IS on SM (Table), Young Imposter Syndrome (YIS) Scale (a validated IS instrument) & assessment of mental health impacts of SM. Results: Out of 195 respondents, 103 answered all questions; median age 40y (27-65), 81% female. 21% were trainees and 36%, 30%, and 12% were early, mid and late-career faculty, respectively. Specialties included: adult H/O (72%), gynecologic oncology (11.3%), radiation oncology (10.5%), surgical oncology (4.1%), and pediatric H/O (1.5%). Twitter was the most commonly used SM platform (68%) followed by FB (36%) & IG (20%). 26% utilized professional SM 0-1 times/week while 28% did so daily. 97/157 (62%) noted positive mental health impacts from SM. 41% felt anxious, lonely or depressed due to SM. 19.7% have experienced SM harassment or cyberbullying. More than 50% of respondents met criteria on the YIS and IS scale; indeed, the YIS and IS on SM Scales were significantly correlated with each other (r = 0.57, p < 0.001, N = 103). The presence of IS on SM was associated with gender but not race/ethnicity or career stage. 59% of females versus 28% of males met criteria for IS (p = 0.02). The presence of IS on SM was significantly associated with self-perceived IS in professional settings (p < 0.001), but not in personal settings (p = 0.21). Conclusions: Many oncology professionals experienced IS while interacting on SM, but also note a positive mental health impact with SM use. The presence of IS on SM correlated with results on the YIS Scale, suggesting a novel assessment method, but further validation is needed. Future efforts to combat IS on SM while enhancing positive aspects of medical SM are warranted. [Table: see text]

PURPOSE: Treatment of locally advanced cervical cancer patients includes chemoradiation followed by brachytherapy. Our aim is to develop a delta radiomics (DRF) model from MRI-based brachytherapy treatment and assess its association with progression free survival (PFS).MATERIALS AND METHODS: A retrospective analysis of FIGO stage IB- IV cervical cancer patients between 2012 and 2018 who were treated with definitive chemoradiation followed by MRI-based intracavitary brachytherapy was performed. Clinical factors together with 18 radiomic features extracted from different radiomics matrices were analyzed. The delta radiomic features (DRFs) were extracted from MRI on the first and last brachytherapy fractions. Support Vector Machine (SVM) models were fitted to combinations of 2-3 DRFs found significant after Spearman correlation and Wilcoxon rank sum test statistics. Additional models were tested that included clinical factors together with DRFs.RESULTS: A total of 39 patients were included in the analysis with a median patient age of 52 years. Progression occurred in 20% of patients (8/39). The significant DRFs using two DRF feature combinations was a model using auto correlation (AC) and sum variance (SV). The best performing three feature model combined mean, AC & SV. Additionally, the inclusion of FIGO stages with the 2- and 3 DRF combination model(s) improved performance compared to models with only DRFs. However, all the clinical factor + DRF models were not significantly different from one another (all AUCs were 0.77).CONCLUSIONS: Our study shows promising evidence that radiomics metrics are associated with progression free survival in cervical cancer.(c) 2023 The Authors. Published by Elsevier Inc. on behalf of American Brachytherapy Society. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

This study highlights the heterogeneity in metrics used by thoracic radiation oncologists and provides levels of consensus on ideal and acceptable dose constraints as guidance for treatment planning. Future directions include using these statements to develop prescription templates and acceptance criteria for treatment planning systems for widespread use as well as extending this Delphi approach to additional disease sites.

Purpose: The changes in the recommended use of radiation therapy (RT) in the presence of expanding systemic cancer therapies and technological advances are poorly characterized. We sought to understand the recommended utilization of RT across a broad range of malignancies by examining National Comprehensive Cancer Network (NCCN) Guidelines. Methods and Materials: We conducted a comprehensive review and categorization of RT recommendations, with their subsequent supporting evidence categories, in 3 versions of NCCN Guidelines, specifically years 2000, 2009, and 2019. These NCCN Guidelines were individually examined for RT-specific recommendations among the 10 most common tumors. The presence of RT as a recommended modality was recorded for each tumor type in each guideline. Recommendation categories including Category 1, 2A, 2B, and 3 were tallied and compared with examine totals and percentage distributions in each tumor type.Results: A total of 3858 NCCN recommendations were individually reviewed. The presence of a recommendation inclusive of RT increased from incidence of 205 in the year 2000 to 992 in the year 2019 (383%). In the 2019 NCCN Guidelines, the most Category 1 RT recommendations were found within small cell lung (13%), non-small cell lung (5%), breast (5%), bladder (2%), rectal (2%), and non-Hodgkin lymphoma (1%). Pancreatic, uterine, prostate, melanoma, kidney, and colon cancer guidelines had no Category 1 RT recommendations. Rectal cancer had 31 (27%) preferred recommendations. The majority (89%) of 2019 RT recommendations were for initial therapy, and 9% were specific to salvage therapy. Tumor sites with the highest proportion of RT Category 1 evidence were small cell lung (29%), non-small cell lung (24%), and breast cancer (24%). Conclusions: The frequency of recommendations for using RT in NCCN Guidelines has increased by >300% in the past 20 years among the 10 most common malignancies. Consideration of the quality of evidence supporting these recommendations by tumor type is useful to identify specific malignancies in need of higher-level evidence supporting the role of RT. Published by Elsevier Inc. on behalf of American Society for Radiation Oncology.

Purpose: Peak fertility commonly occurs during medical training, and delaying parenthood can complicate pregnancies. Trainee parental leave policies are varied and lack transparency. Research on the impacts of parenthood on trainee education is limited. Methods: A Qualtrics-based survey was distributed via e-mail/social media to program directors (PDs) within oncologic specialties with a request to forward a parallel survey to trainees. Questions assessed awareness of parental leave policies, supportiveness of parenthood, and impacts on trainee education. Statistical analyses included descriptive frequencies and bivariable comparisons by key groups. Results: A total of 195 PDs and 286 trainees responded. Twelve percent and 29% of PDs were unsure of maternity/paternity leave options, respectively. PDs felt they were more supportive of trainee parenthood than trainees perceived they were. Thirty-nine percent of nonparent trainees (NPTs) would have children already if not in medicine, and >80% of women trainees were concerned about declining fertility. Perceived impacts of parenthood on trainee overall education and academic productivity were more negative for women trainees when rated by PDs and NPTs; however, men/women parents self-reported equal impacts. Leave burden was perceived as higher for women trainees. Conclusions: A significant portion of PDs lack awareness of parental leave policies, highlighting needs for increased transparency. Trainees' perception of PD support for parenthood is less than PD self-reported support. Alongside significant rates of delayed parenthood and fertility concerns, this poses a problem for trainees seeking to start a family, particularly women who are perceived more negatively. Further work is needed to create a supportive culture for trainee parenthood.