bluuebunny/crossref_metadata_2025_split huggingface dataset:
RADT-02. PRE-OPERATIVE VERSUS POST-OPERATIVE FRACTIONATED STEREOTACTIC RADIOTHERAPY: A SINGLE-INSTITUTION ANALYSIS OF 534 RESECTED METASTASES
Authors: Perlow Haley , Hennings Sarah , Bradshaw Jared , Reddy Sohil , Luu Sydney , Matsui Jennifer , Klamer Brett , Dibs Khaled , Harrell Marshall , McGregor John , Lonser Russell , Prevedello Daniel , Elder James , Wu Kyle , Prabhu Roshan , Zhu Simeng , Singh Raj , Beyer Sasha , Grecula John , Blakaj Dukagjin , Thomas Evan , Raval Raju , Palmer Joshua 
Published: November 2024

Abstract
Patients with large or symptomatic brain metastases and limited intracranial disease typically have surgery followed by post-operative (post-op) stereotactic radiosurgery (SRS). However, SRS can lead to elevated rates of radiation necrosis (RN), meningeal disease (MD), and local failure (LF). Fractionated treatments can deliver a higher biological effective dose and may reduce the risk of LF, and pre-operative (pre-op) treatments may reduce the risk of RN and MD through treating smaller volumes and tumor sterilization. We hypothesize that pre-op fractionated stereotactic radiation therapy (FSRT) will reduce the incidence rate of RN, MD, and LF when compared to patients who receive post-op FSRT. A retrospective analysis was performed at a single institution and included patients who had surgical resection and radiation to at least one brain metastasis. Patients with multiple metastases resected, either during the same surgery or at different times in the disease course, were eligible for inclusion. Outcomes were evaluated on a per-lesion basis. The primary outcome was a composite endpoint defined by 1) LF, 2) MD, and/or 3) Grade 2 or higher (symptomatic) RN. 458 patients with 534 resected brain metastases were eligible for analysis. 235 metastases received pre-op FSRT, and 299 metastases received post-op FSRT. Overall, 15% of patients had multiple brain metastases resected. Overall, 6 (2.6%) pre-op and 13 (4.3%) post-op patients experienced LF. 21 (8.9%) pre-op and 38 (12.7%) post-op patients experienced symptomatic RN. 11 (4.7%) pre-op and 29 (9.7%) post-op patients were diagnosed with MD (p=0.031). 14% and 24% of metastases that received pre-op and post-op FSRT, respectively, experienced the composite endpoint (p=0.005). In our study, pre-op FSRT compares favorably to post-op FSRT primarily due to a 50% reduction in the incidence of MD. Differences in symptomatic RN or LF were small on adjusted analyses. Prospective validation of pre-op FSRT is needed.
RADT-03. CONTRAST-ENHANCING LESIONS INDUCED BY CNS-DIRECTED INTENSITY MODULATED PROTON THERAPY: DEMOGRAPHIC AND CARDIOVASCULAR RISK FACTORS ANALYSIS
Authors: Gal Omer , Yu Jen , Mehta Minesh P , Hall Matthew D , Press Robert H , Odia Yazmin , McDermott Michael W , Fellows Zachary , Wroe Andrew , Gutierrez Alonso N , Kotecha Rupesh 
Published: November 2024

Abstract

INTRODUCTION
Lesions exhibiting radiation-induced contrast enhancement (RICE) may develop following cranial intensity modulated proton therapy (IMPT). The mechanisms underlying their development may be shared or amplified by existing patient comorbidities. The objective of this study was to assess a potential relationship between individual or composite cardiovascular risk criteria and RICE development, independent of dosimetric considerations.

METHODS
Data were reviewed for patients treated at a single tertiary care institution between 2017-2023. Time to RICE development was assessed using Kaplan-Meier. Cox regression analysis was used to determine hazard ratios (HRs) with 95% confidence intervals (CIs). Host-related risk factors for RICE development were assessed in a univariable analysis (UVA). A binary logistic regression model was built to ascertain the effects of age and cardiovascular risk factors on the likelihood of developing RICE (expressed as QRISK3 relative risk).

RESULTS
The study cohort included 137 patients; the median age was 40 years (range: 1-85), 51% female, and 53% Hispanic. Cardiovascular risk factors included smoking (18% past, 6% current), diabetes (7%), hypertension (22%), dyslipidemia (15%) and high body mass index (BMI, 50% were obese with BMI&gt;25). At a median follow-up of 3 years, RICE developed in 36 (26%) patients. On UVA, RICE development was only associated with age ≥18 compared to &lt;18 (HR 3.3, 95% CI: 1.2-9.4, p=0.024). None of the other evaluated risk factors were significantly associated with RICE (p&gt;0.05). Additionally, logistic regression analysis showed increasing age was associated with likelihood of developing RICE (χ2=6.95, p=0.031), while QRISK3 score was not.

CONCLUSIONS
In this contemporary series of patients treated with IMPT, age was the only host factor associated with RICE, while other cardiovascular risk factors, evaluated individually or using established composite risk scores (QRISK3) were not associated with RICE. Additional research is needed to identify potential patient characteristics associated with RICE.
RADT-08. THIRD RECURRENT WHO 1 SPINAL MENINGIOMAS. CASE SERIES AND CLINICAL OUTCOMES FOLLOWING SURGERY OR DEFINITIVE RADIOTHERAPY
Authors: Haisraely Ory 
Published: November 2024

Abstract

INTRODUCTION
Spinal meningiomas (SM) account for approximately 1.2–12.7% of all meningiomas and 25% of spinal cord tumors. Most are benign (WHO grade 1), but a small percentage are atypical (WHO grade 2) or anaplastic (WHO grade 3). These tumors are typically solitary and non-invasive with low recurrence rates post-surgery. This study aims to compare the efficacy of definitive radiotherapy (RT) versus third surgery for recurrent SM WHO grade 1, focusing on local control, progression-free survival (PFS), and toxicity.

METHODS
A retrospective review approved by the Institutional Review Board included patients diagnosed with recurrent SM WHO grade 1 who underwent second surgery between 2008-2020. Patients who received radiation after the first surgery or upgraded to WHO grade 2 or 3 were excluded. Data on demographics, tumor characteristics, surgical techniques, and radiation therapy details were analyzed using descriptive and inferential statistics.

RESULTS
The study included 48 cases of third progression SM WHO grade 1. The median age was 53 years, and 70.8% were female. Tumor locations were primarily thoracic (75%). There was no significant difference in PFS between the third surgery and RT groups, with 36-month PFS rates of 77.4% and 76.4%, respectively. RT-related toxicities were manageable, and neurological improvements were noted in both groups, with more pronounced improvements in the surgical group. RT showed better pain control outcomes.

CONCLUSION
Both definitive RT and third surgery are effective for managing recurrent SM WHO grade 1, with comparable PFS. RT is a viable alternative, especially for high-risk surgical patients, providing effective pain control and manageable toxicities. Further studies with larger cohorts and longer follow-ups are recommended to validate these findings and refine treatment protocols for recurrent SM, ultimately improving patient outcomes and quality of life.
RADT-11. FACTORS ASSOCIATED WITH LOCAL FAILURE AFTER STEREOTACTIC RADIATION TO THE SURGICAL BED OF BREAST CANCER PATIENTS WITH A SINGLE BRAIN METASTASIS
Authors: Haisraely Ory , Taliansky Alicia , Kaidar Orit Person 
Published: November 2024

Abstract

BACKGROUND
Metastatic breast cancer is the second most common cancer associated with brain metastases (BCBM). In our study we evaluated variables that influence local control in this breast cancer patients with a single BCBM who underwent surgical resection and stereotactic radiation to resection cavity.

METHODS
After ethics approval, we conducted a retrospective review of the medical records of BCBM patients treated with stereotactic radiation for BCBM between 2011 to 2022. Only breast cancer patients with a single BCBM who underwent surgical resection and stereotactic radiation to the surgical cavity were included. Clinical and dosimetric variables were analyzed to evaluate their impact on local control. Statistical analysis included descriptive analyses. X2 test was used for categorical variables. Total dose, dose per fraction, biologically effective dose (BED), and planning target volumes were analyzed as both continuous and categorical variables at different thresholds. A binary regression model was applied to study variables shown to impact local control.

RESULTS
A total of 62 patients included local control was 70.9% at 12 months. HER-2 disease, luminal-B, size of BCBM, time from craniotomy, total dose, inclusion of corridor, and non-cystic lesion were significant for local control.

CONCLUSION
Our data supports previous publications about the importance of tumor bed delineation, dose and fractionation, and time from craniotomy as factors associated with better local control. Our study shows that the role of BCBM subtype and new systemic therapies in contributing to local and intracranial control should be further explored.
RADT-22. EFFICACY AND SAFETY OF CYBERKNIFE STEREOTACTIC RADIOSURGERY FOR OCCIPITAL CONDYLE METASTASIS
Authors: Park David , Kattaa Ahed , Chang Steven 
Published: November 2024

Abstract

BACKGROUND
Occipital condyle metastasis (OCM) is a rare condition characterized by severe occipital pain and neurological symptoms due to lower cranial nerve deficits, stemming from its anatomical location. Despite the widespread use of stereotactic radiosurgery (SRS) for cranial metastases, its specific impact on OCM remains underexplored.

OBJECTIVE
This study evaluates the efficacy and safety of CyberKnife SRS in treating OCM, focusing on symptom control and local tumor control.

METHOD
We retrospectively analyzed cases of OCM treated with SRS at our institute from 2012 to 2023, evaluating patient demographics, presenting symptoms, treatment parameters, and outcomes. Key measures included occipital pain, dysfunctions of cranial nerves IX, X, and XII, and local tumor control.

RESULTS
Eighteen patients (10 females) with a median age of 64 years (range: 40-79) were treated. Common presentations included occipital pain (44%) and lower cranial nerve deficits (28%). The median target volume was 6.95 cc (range: 0.95-72.7), and the median margin dose was 20 Gy (range: 16-40). The median follow-up period was 7 months (range: 1-44). Notably, only one patient experienced tumor recurrence and subsequently died from primary cancer progression five months after treatment. SRS achieved a 93.8% local tumor control rate over three years, with a median overall survival of 13 months. Among those presenting with symptoms, 87.5% reported pain relief, and 80% observed improvements in cranial nerve function. The only patient without clinical symptom improvement also had tumor recurrence.

CONCLUSION
CyberKnife SRS is a promising treatment for OCM, offering significant pain relief and improvement in neurological symptoms with excellent local control rates. This non-invasive therapy provides a valuable alternative to surgery, potentially enhancing the quality of life for patients with limited treatment options due to this challenging condition.
RADT-23. MOLECULAR PROFILING OF GLIOMAS: INSIGHTS INTO RADIONECROSIS AND PSEUDOPROGRESSION THROUGH NEXT-GENERATION SEQUENCING
Authors: Santos Monica , Restini Felipe , Fagundes Sayonara , Moraes Fábio , Marta Gustavo , Hanna Samir , Maldaun Marcos 
Published: November 2024

Abstract

BACKGROUND
Gliomas, the most common primary tumors of the CNS, presenting diagnostic and therapeutic challenges due to their heterogeneity. Next-generation sequencing (NGS) enhances diagnostic precision by identifying genetic alterations, guiding accurate diagnosis and personalized treatment strategies. Post-treatment complications such as radionecrosis and pseudoprogression present additional diagnostic difficulties, often mimicking tumor recurrence. This study aimed to evaluate the association between genetic alterations detected by NGS and treatment-related complications.

METHODS
This retrospective study analyzed data from electronic medical records at a Brazilian Radiation Therapy Department (2018-2023). The study included patients with gliomas who underwent surgical resection followed by adjuvant radiochemotherapy and subsequently developed complications such as radionecrosis and pseudoprogression. Genetic alterations detected by the HSL 500 (NGS) test were evaluated for their association with these complications using Fisher’s Exact Test.

RESULTS
Out of 192 patients treated for glioma, 46 (23.96%) experienced treatment-related complications, with 20 patients having available NGS test results. Among these, eight cases were identified as pseudoprogression, fifteen as radionecrosis, with three patients presenting both conditions. All 20 patients with NGS results were diagnosed with high-grade gliomas, eight of whom underwent reirradiation, resulting in two cases of radionecrosis post-reirradiation. Although no statistically significant association was found between genetic alterations and radionecrosis or pseudoprogression, specific mutations were prevalent in each group. In radionecrosis cases, the most common mutations were TERT promoter (c.1-124C&gt;T) (n=9, p=0.613) and EGFR amplification (n=8, p=1.0). In pseudoprogression, frequent mutations included TERT promoter (c.1-124C&gt;T) (n=6, p=0.642), EGFR (n=5, p=0.67), PTEN (n=4, p=1.0), NF1 (n=2, p=0.537), and P53 (n=2, p=0.197).

CONCLUSION
Molecular testing for glioma characterization is crucial for diagnosis and prognosis, aiding in understanding treatment-related complications. Strategies to avoid radionecrosis and pseudoprogression are vital to improve patient quality of life, especially in high-grade gliomas. Further studies are needed to confirm these trends and explore clinical relevance of mutations.
RADT-24. WALLERIAN DEGENERATION OF THE CORTICOSPINAL TRACT IN GLIOMAS: A RETROSPECTIVE ANALYSIS AND A SYSTEMATIC REVIEW OF MOTOR FUNCTION IN ELOQUENT AREAS POST-RADIATION THERAPY. HOW IMPORTANT IS MOTOR FUNCTION FOR PATIENTS WITH GLIOMAS IN RADIATION THERAPY?
Authors: Santos Monica , Rodrigues Natasha , Gibram Franceliny , Brunelli Julia , Mancini Anselmo , Moraes Fábio , Marta Gustavo , Hanna Samir , Maldaun Marcos 
Published: November 2024

Abstract

BACKGROUND
The quality of life for patients with gliomas is significantly impacted by tumor characteristics, treatment modalities, and radiation dosages. Variability in radiotherapy protocols and differences in tissue tolerance necessitate a detailed risk-benefit assessment, especially in eloquent brain areas responsible for motor functions.

METHODS
A retrospective analysis of electronic medical records from a Brazilian Radiation Therapy Department (2018-2023) was conducted. Patients with gliomas who underwent surgical resection and adjuvant radiochemotherapy, subsequently developing Wallerian Degeneration of the Corticospinal Tract (WDCT), were included. Additionally, a systematic search was performed in PubMed, Embase, and Cochrane databases, focusing on radiotherapy in eloquent areas and evaluating motor function. Of the 1,064 studies identified, 11 underwent full-text review by two independent examiners.

RESULTS
Among 192 glioma patients, 13 (6.77%) developed WDCT, all with high-grade gliomas, including 3 post-reirradiation cases. Retrospective dosimetric analysis of the corticospinal tract was performed for two patients who had tractography. Patient 1, with right frontoparietal tumor, had an ipsilateral corticospinal tract volume of 10.6 cm³, a max dose of 62.81 Gy, and 0.5 cc receiving 62.2 Gy; the contralateral tract volume was 18.5 cm³, with 0.5 cc receiving 51 Gy. Patient 2, with right frontal tumor, had an ipsilateral corticospinal tract volume of 31.1 cm³, a max dose of 42.76 Gy, and 0.5 cc receiving 42.37 Gy; the contralateral tract volume was 30.3 cm³, with 0.5 cc receiving 24.19 Gy. The systematic review identified 5 studies reporting pre- and post-radiotherapy motor outcomes in eloquent areas, with 4 focusing exclusively on gliomas. However, heterogeneity in radiotherapy techniques and outcome assessments precluded a meta-analysis.

CONCLUSION
Motor function in glioma patients undergoing radiation therapy remains an underexplored area. Future studies should focus on standardized assessments of functional outcomes to establish dose constraints and optimize treatment protocols, thus improving the quality of life for glioma patients.
RADT-29. ASSOCIATION OF ANATOMIC PROXIMITY OF BRAIN PARENCHYMAL METASTASIS TO THE CSF SPACE AND UPFRONT STEREOTACTIC RADIOSURGERY TO SUBSEQUENT LEPTOMENINGEAL METASTASIS DEVELOPMENT IN BRAIN METASTATIC NSCLC
Authors: Bashir Shoaib , Hong Weiping , Lai Mingyao , Cai Linbo 
Published: November 2024

Abstract

OBJECTIVE
The most common solid systemic malignancies that metastasize to the leptomeninges are lung cancer, especially non-small cell lung cancer (NSCLC). Generally, patients develop leptomeningeal metastasis (LM) subsequent to brain parenchymal metastases (BM). However, its predictors remain unknown. Hence, the present study was carried out to explore the predictors of LM in brain metastatic NSCLC patients.

METHODS
The final analysis included 112 pathologically definite NSCLC patients with BMs treated in our center between July 1, 2014, and December 30, 2020. Of 112, one-half had LM. Three radiologists analyzed radiologic images independently. Anatomic proximity of BMs to the CSF space (dural-based metastases, periventricular or major CSF cisterns such as basal cisterns and cisterna magna) was measured and stratified into CSF space invading/bordering and detached lesions. The endpoint was the occurrence of LM or death, whichever occurred first. Univariable and multivariable logistic regressions were performed to identify potential predictors for LM.

RESULTS
Of 112, 48 (42.8%) were males, and 64 (57.2%) were females. Most patients (90.2%) had adenocarcinoma histology. The median follow-up time was 10.1 months (IQR, 4.2-18.4 months) following BM diagnosis. Univariate logistic regression analysis demonstrated that histology (OR 0.084, 95%CI 0.004-0.461, P=0.020), EGFR/ALK/ROS1 mutation (OR 3.868, 95%CI 1.583-10.079, P=0.003), CSF space invading/bordering lesion (OR 10.278, 95%CI 4.203-27.375, P=0.000), extracranial metastasis control (OR 2.7, 95%CI 1.191-6.309, P=0.019), upfront stereotactic radiosurgery (SRS) (OR 0.024, 95%CI 0.001-0.12, P=0.000), and target therapy (OR 4.476, 95%CI 1.877-11.464, P=0.001) were the potential predictor. CSF space invading/bordering lesion (OR 7.443, 95%CI 2.099-32.853, P=0.003) and upfront SRS (OR 0.035, 95%CI 0.002-0.212, P=0.003) remained statistically significant in the multivariate logistic regression analysis.

CONCLUSION
CSF space invading/bordering BMs may increase the risk of LM development in brain metastatic NSCLC patients, while upfront SRS targeting BM potentially decreases the risk. A prospective study is warranted to affirm.
RADT-30. MANAGEMENT OF PRESUMED PSEUDOPROGRESSION WITH EARLY BEVACIZUMAB IN THE THREE MONTHS AFTER HIGH DOSE RADIATION THERAPY FOR GLIOBLASTOMA
Authors: Back Michael , Challis Benjamin , Horsley Patrick , Kastelan Marina , Cove Nicola , Jackie Yim , Drummond James , Wong Matthew , Lee Adrian , Wheeler Helen 
Published: November 2024

Abstract

BACKGROUND
Optimal management for symptomatic steroid-refractory pseudoprogression (rPsP) following IMRT for Glioblastoma remains poorly defined. This study examined radiological volumetric response and clinical outcomes following use of early Bevacizumab (earlyBEV), defined as commencing during or within 3 months of IMRT.

METHODS
Consecutive patients managed with Stupp60Gy IMRT between 2016-2023 for Glioblastoma were analysed for those patients receiving earlyBEV for rPsP. Volumetric analysis was performed with sequential MRI T1gd/T2 sequences using preBEV and postBEV scans. Primary endpoint was volumetric reduction of T1gd/T2 volumes at month+2/3 postBEV. Clinical response, overall survival and pattern of relapse, specifically distant failure was assessed.

RESULTS
Forty-one (14%) of 289 patients received earlyBEV for rPsP, with median follow-up of 9.9months (q1-3:8-25) for survivors. Compared to remaining 248 patient cohort, earlyBEV had worse initial ECOG0,1 (50%vs76%); less near-total resection (5%vs42%); and less MGMT methylation (35%vs46%). Additionally at diagnosis the initial tumours had larger T1gd and T2 volumes. Median time to commencement of earlyBEV was 1.4months postIMRT; including seven patients during IMRT. All patients responded to BEV, with reduction in symptoms, steroid use and radiological volume, though one died pre-assessment. Median T1gd and T2 volumes before earlyBEV were 37cm3 (q1-3:23-63cm3) and 116cm3 (q1-3:90-148cm3) respectively, which were 95% and 78% larger than at diagnosis. Median survival postBEV was 8.1months (95%CI:7.5-8.6). Median volumes postBEV reduced to 16cm3 (q1-3:8-23cm3) and 41cm3 (29-55cm3); which was a percentage reduction for T1gd and T2 of 57% and 65%. Midline shift reduced from 5mm(q1-3:3-8mm) to zero in two-thirds of patients. Patients requiring earlyBEV had worse survival compared to remaining cohort (p&lt;0.001); with median OS 11.9months (95%CI:10.4-13.5) vs 19.9months (95%CI:18.4-21.5). A component of distant relapse was evident in 48% of earlyBEV vs 34% in remaining cohort. One serious adverse event occurred with fatal intracranial haemorrhage day10 after initial BEV dose.

CONCLUSION
This study data confirms efficacy of earlyBEV for managing steroid-refractory pseudoprogression, but also the worse prognosis of this high-risk cohort.
RADT-35. PATTERNS OF INTRACRANIAL RESPONSE AND RELAPSE AFTER CNS-DIRECTED RADIOTHERAPY (CNS-RT) FOR PATIENTS WITH CHEMOREFRACTORY OR PROGRESSIVE SECONDARY CNS LYMPHOMA (SCNSL)
Authors: Cederquist Gustav , Tringale Kathryn , Hajj Carla , Moore Zachary , Hubbeling Harper , Dreyfuss Alexandra , Fregonese Beatrice , Falchi Lorenzo , Scordo Michael , Grommes Christian , Yahalom Joachim , Imber Brandon 
Published: November 2024

Abstract

PURPOSE/OBJECTIVE
Progressive SCNSL after failure of CNS-directed systemic therapy is a challenging clinical scenario. CNS-RT can effectively salvage, but its optimal role is poorly defined.

METHODS
We analyzed diffuse large B-cell patients who received brain RT for progressive SCNSL following 1+ line of therapy for active SCNSL (not prophylaxis). Overall survival (OS) was calculated by Kaplan-Meier and RT response was evaluated using IPCG or RANO criteria for parenchymal or leptomeningeal disease, respectively. Risk of intracranial failure assumed death as a competing risk. Pre-RT SCNSL patterns were classified as parenchymal-only versus diffuse (periventricular or leptomeningeal). Local failure was progression only of pre-RT lesion(s).

RESULTS
We identified 55 patients with median follow up of 3.5m. 85% had neurologic symptoms, 45% had extracranial disease. Patients received a median of 2 prior SCNSL-directed therapies (IQR 1-3); 91% received methotrexate-based regimens with median 21d between last methotrexate and RT. Median CNS-RT dose was 30 Gy in 10 fractions delivered to whole brain (n=44, 80%), partial brain (n=9, 16%), or craniospinal axis (n=2, 4%). Median OS was 3.5m. Overall response for 38 evaluable was 79% (24% complete), with median of 60d to best response. 58% were successfully bridged with CNS-RT to subsequent therapies and 12m intracranial failure risk was 37% for those bridged, and 64% for those not bridged (p=0.05). 19 had parenchymal-only disease (10 unifocal, 9 multifocal) with median largest lesion diameter 4.1cm (range 1.7–7.4). 19 had diffuse pattern (12 periventricular, 7 leptomeningeal). 7 with parenchymal-only disease failed intracranially, 5 of which were local. 8 with diffuse disease failed intracranially, only 1 of which was local (p = 0.035).

CONCLUSION
SCNSL patients referred for RT had symptomatic, treatment-refractory disease. While CNS-RT response rates were high, duration was often limited, suggesting RT is best used for bridging/palliation. Patients with parenchymal-only disease were enriched for local failure, suggesting potential suitability of involved site CNS-RT, though further validation is needed.