Surgical Resection Followed by Stereotactic Radiosurgery (S+SRS) Versus SRS Alone for Large Posterior Fossa Brain Metastases: A Comparative Analysis of Outcomes and Factors Guiding Treatment Modality Selection.

Background/objectives: Around 20% of cancer patients will develop brain metastases (BrMs), with 15-25% occurring in the posterior fossa (PF). Although the effectiveness of systemic therapies is increasing, surgery followed by stereotactic radiosurgery (S+SRS) versus definitive SRS remains the mainstay of treatment. Given the space restrictions within the PF, patients with BrMs in this location are at higher risk of brainstem compression, hydrocephalus, herniation, coma, and death.

Pituitary neuroendocrine tumors treated with stereotactic radiosurgery.

Purpose: Pituitary neuroendocrine tumors (pitNETs) are benign tumors that may recur after surgical resection or persist following medical management. The objective of this study was to evaluate outcomes and toxicities of patients with pitNETs treated with stereotactic radiosurgery (SRS) at a single institution.

Methods: We completed a retrospective, single-institution study of patients with pitNETs treated with frame-based, single-fraction, cobalt-60 SRS between September 2005 and June 2023.

Outcomes with non-small cell lung cancer and brain-only metastasis.

Background: We evaluated outcomes in non-small cell lung cancer (NSCLC) patients who presented with brain-only metastatic (BOM) disease overall and by EGFR/ALK mutation status.

Methods: We analyzed clinico-demographic, treatment and survival data for all NSCLC patients who presented to our center between 2014 and 2016 with BOM as their first presentation of metastatic disease. Differences in overall survival (OS) were evaluated using log-rank tests for NSCLC wildtype (NSCLCwt NSCLC with an ALK-rearrangement/EGFR-mutation (NSCLCmut+).

Radiomic-based prediction of lesion-specific systemic treatment response in metastatic disease.

Despite sharing the same histologic classification, individual tumors in multi metastatic patients may present with different characteristics and varying sensitivities to anticancer therapies. In this study, we investigate the utility of radiomic biomarkers for prediction of lesion-specific treatment resistance in multi metastatic leiomyosarcoma patients. Using a dataset of n=202 lung metastases (LM) from n=80 patients with 1648 pre-treatment computed tomography (CT) radiomics features and LM progression determined from follow-up CT, we developed a radiomic model to predict the progression of each lesion.

The incidence of brain metastases in breast cancer according to molecular subtype and stage: a 10-year single institution analysis.

Background: Breast cancer (BC) is the second most common etiology of brain metastases (BrM). We aimed to examine the incidence of BrM among all BC patients presenting to a large tertiary cancer centre over one decade.

Methods: We included all BC patients presenting consecutively between 2009 and 2019 and cross referenced that cohort to a radiotherapy database, identifying patients treated for BrM at any time following their initial presentation.

Photoinduced Magnetic Exchange-Jump Promotes Ground State Biradical Electron Spin Polarization.

Photoinduced electron spin polarization (ESP) is reported in the electronic ground states of three Pt(II) complexes comprised of two S = 1/2 nitronyl nitroxide (NN) radicals attached through different length -phenylethynyl bridges to the 3,6 positions of a catecholate (CAT, donor) and 4,4'-di--butyl-2,2'-bipyridine (bpy, acceptor). Complexes - have from 17 to 41 bonds separating NN radicals and display cw-EPR spectra consistent with || ≫ ||, || ≥ ||, and || < ||, respectively, where is the magnetic exchange coupling between NN radicals in the electronic ground state, and is the isotropic N hyperfine coupling constant. Light-induced transient EPR spectra characterized as enhanced ground-state absorption were observed for all three complexes using 532 nm pulsed laser excitation into the ligand-to-ligand charge transfer (LL'CT) band of the (CAT)Pt(bpy) chromophore.

Metal-Ligand Exchange Coupling Alters the Open-Shell Ligand Electronic Structure in a Bis(semiquinone) Complex.

The electronic structure of the bis(dioxolene) bridging ligand -- is responsive to metal-ligand magnetic exchange coupling. Comparison of the crystal structure of to that of indicates an open-shell biradical ground state for the dinuclear Ni(II) complex compared to the closed-shell quinoidal character found in the dinuclear Zn(II) complex. Consistent with a comparison of bond lengths obtained by X-ray diffraction, the analysis of the variable-temperature magnetic susceptibility data for crystalline yields reduced SQ-SQ radical-radical magnetic exchange coupling ( = -203 cm) compared to that of ( = -321 cm).

Rate of pachymeningeal failure following adjuvant WBRT vs SRS in patients with brain metastases.

Background: Stereotactic radiosurgery (SRS) has supplanted whole brain radiotherapy (WBRT) as standard-of-care adjuvant treatment following surgery for brain metastasis (BrM). Concomitant with the adoption of adjuvant SRS, a new pattern of failure termed "Pachymeningeal failure" (PMF) has emerged.

Methods: We reviewed a prospective registry of 264 BrM patients; 145 and 119 were treated adjuvantly with WBRT and SRS, respectively.

Variation from closed-shell to open shell electronic structures in oligothiophene bis(dioxolene) complexes.

A series of oligothiophene bis(dioxolene) complexes, SQ-Th-SQ (SQ = = ½TpZn(3--butyl-orthosemiquinonate); Tp = tris(5-cumenyl-3-methylpyrazolyl)borate anion) have been synthesized, structurally characterized, and studied as a function of the number of thiophene bridging units, ( = 0-3) using a combination of variable-temperature (VT) electronic absorption and EPR spectroscopies, and VT magnetic susceptibility measurements. The thiophene bridge bond lengths determined by X-ray crystallography display dramatic differences across the SQ-Th-SQ series. Bridge bond deviation values (Σ||) display a progressive change in the nature of the bridge fragment bonding as the number of thiophene groups increases, with quinoidal bridge character for = 1 (SQ-Th-SQ) and biradical character with "aromatic" bridge bond lengths for = 3 (SQ-Th-SQ).

Radiomic-Based Prediction of Lesion-Specific Systemic Treatment Response in Metastatic Disease.

Despite sharing the same histologic classification, individual tumors in multi metastatic patients may present with different characteristics and varying sensitivities to anticancer therapies. In this study, we investigate the utility of radiomic biomarkers for prediction of lesion-specific treatment resistance in multi metastatic leiomyosarcoma patients. Using a dataset of n=202 lung metastases (LM) from n=80 patients with 1648 pre-treatment computed tomography (CT) radiomics features and LM progression determined from follow-up CT, we developed a radiomic model to predict the progression of each lesion.

Competitive reversed quartet mechanisms for photogenerated ground state electron spin polarization.

Photoinduced electron spin polarization (ESP) of a spin-½ organic radical (nitronyl nitroxide, NN) in a series of Pt(ii) complexes comprised of 4,4'-di--butyl-2,2'-bipyridine (bpy) and 3--butylcatecholate (CAT) ligands, where the CAT ligand is substituted with (CH)--phenyl-NN (bridge-NN) groups, is presented and discussed. We show the importance of attenuating the energy gap between localized NN radical and chromophoric excited states to control both the magnitude and sign of the optically-generated ESP, and to provide deeper insight into the details of the ESP mechanism. Understanding electronic structure contributions to optically generated ESP will enhance our ability to control the nature of prepared states for a variety of quantum information science applications, where strong ESP facilitates enhanced sensitivity and readout capabilities at low applied magnetic fields and higher temperatures.

Individualized Stereotactic Ablative Radiotherapy for Lung Tumors: The iSABR Phase 2 Nonrandomized Controlled Trial.

Importance: Stereotactic ablative radiotherapy (SABR) is used for treating lung tumors but can cause toxic effects, including life-threatening damage to central structures. Retrospective data suggested that small tumors up to 10 cm3 in volume can be well controlled with a biologically effective dose less than 100 Gy.

Objective: To assess whether individualizing lung SABR dose and fractionation by tumor size, location, and histological characteristics may be associated with local tumor control.

Recommended first-line management of asymptomatic brain metastases from EGFR mutant and ALK positive non-small cell lung cancer varies significantly according to specialty: an international survey of clinical practice.

Background: The role for radiotherapy or surgery in the upfront management of brain metastases (BrM) in epidermal growth factor receptor mutant (m) or anaplastic lymphoma kinase translocation positive (+) non-small cell lung cancer (NSCLC) is uncertain because of a lack of prospective evidence supporting tyrosine kinase inhibitor (TKI) monotherapy. Further understanding of practice heterogeneity is necessary to guide collaborative efforts in establishing guideline recommendations.

Methods: We conducted an international survey among medical (MO), clinical (CO), and radiation oncologists (RO), as well as neurosurgeons (NS), of treatment recommendations for asymptomatic BrM (in non-eloquent regions) EGFRm or ALK+ NSCLC patients according to specific clinical scenarios.

Corrigendum: What if: a retrospective reconstruction of resection cavity stereotactic radiosurgery to mimic neoadjuvant stereotactic radiosurgery.

[This corrects the article DOI: 10.3389/fonc.2023.

A total inverse planning paradigm: Prospective clinical trial evaluating the performance of a novel MR-based 3D-printed head immobilization device.

Background And Purpose: Brain radiotherapy (cnsRT) requires reproducible positioning and immobilization, attained through redundant dedicated imaging studies and a bespoke moulding session to create a thermoplastic mask (T-mask). Innovative approaches may improve the value of care. We prospectively deployed and assessed the performance of a patient-specific 3D-printed mask (3Dp-mask), generated solely from MR imaging, to replicate a reproducible positioning and tolerable immobilization for patients undergoing cnsRT.

Toxicity and outcomes of melanoma brain metastases treated with stereotactic radiosurgery: the risk of subsequent symptomatic intralesional hemorrhage exceeds that of radiation necrosis.

Purpose: We aimed to assess the outcomes and patterns of toxicity in patients with melanoma brain metastases (MBM) treated with stereotactic radiosurgery (SRS) with or without immunotherapy (IO).

Methods: From a prospective registry, we reviewed MBM patients treated with single fraction Gamma Knife SRS between 2008 and 2021 at our center. We recorded all systemic therapies (chemotherapy, targeted therapy, or immunotherapy) administered before, during, or after SRS.

Winning a Nobel Prize may be bad for your productivity.

Fame and time commitments that come with the honor distract from continued research.

Radiation-induced sarcomas following childhood cancer - A Canadian Sarcoma Research and Clinical Collaboration Study (CanSaRCC).

Background: Radiation-induced sarcoma (RIS) is a late toxicity of radiation therapy (RT) usually associated with poor prognosis. Due to ongoing improvements in childhood cancer treatment and patient outcomes, RIS may become more prevalent notwithstanding evolving indications for RT. Due to limited reported studies, we sought to review our experience with RIS in survivors of pediatric cancer.

Anatomical and surgical characteristics correlate with pachymeningeal failure in patients with brain metastases after neurosurgical resection and adjuvant stereotactic radiosurgery.

Purpose: Neurosurgery (NS) is an essential modality for large brain metastases (BM). Postoperative stereotactic radiosurgery (SRS) is the standard of care adjuvant treatment. Pachymeningeal failure (PMF) is a newly described entity, distinct from classical leptomeningeal failure (LMF), that is uniquely observed in postoperative patients treated with adjuvant SRS.

What if: A retrospective reconstruction of resection cavity stereotactic radiosurgery to mimic neoadjuvant stereotactic radiosurgery.

Introduction: Neoadjuvant stereotactic radiosurgery (NaSRS) of brain metastases has gained importance, but it is not routinely performed. While awaiting the results of prospective studies, we aimed to analyze the changes in the volume of brain metastases irradiated pre- and postoperatively and the resulting dosimetric effects on normal brain tissue (NBT).

Methods: We identified patients treated with SRS at our institution to compare hypothetical preoperative gross tumor and planning target volumes (pre-GTV and pre-PTV) with original postoperative resection cavity volumes (post-GTV and post-PTV) as well as with a standardized-hypothetical PTV with 2.

Review of 20 years of adult medulloblastoma treatment: Chemotherapy prescription trends and survival.

Background: The historic standard of care for adult medulloblastoma has been considered surgery and radiation, while chemotherapy is increasingly being prescribed. This study reviewed 20-year chemotherapy trends at a high-volume center, as well as overall and progression free-survival.

Methods: Adults with medulloblastoma treated at an academic center from January 1, 1999 to -December 31, 2020 were reviewed.

Assessment of intra-fraction motion during frameless image guided Gamma Knife stereotactic radiosurgery.

As frameless stereotactic radiosurgery increase in use, the aim of this study was to evaluate intra-fraction motion through cone-beam CT (CBCT) and high-definition motion management (HDMM) systems. Intra-fraction motion measured between localization, repeat localization and post-treatment CBCTs were correlated to intra-faction motion indicated by the HDMM files using the Pearson coefficient (r). A total of 302 plans were reviewed from 263 patients (114 male, 149 female); 216 pairs of localization-repeat localization, and 260 localization-post-treatment CBCTs were analyzed against HDMM logs.