DSpace Community:

CdSe/CdZnS core/shell nanocrystal scintillators: Light yield, decay time, and solvent effects

Mon, 01 Jun 2026 00:00:00 GMT

Title: CdSe/CdZnS core/shell nanocrystal scintillators: Light yield, decay time, and solvent effects Authors: Boo, Jihwan; Kim, Byong Jae; Kim, Nam Young; Han, Ill-hyuk; Lim, Soobin; Lim, Jaehoon; Kim, Geehyun Abstract: Semiconductor nanocrystals (NCs) have emerged as promising candidates for next-generation scintillators owing to their tunable band gaps and high photoluminescence quantum yields (PLQYs). However, most NC-based scintillators rely on polymer or solvent matrices, in which inefficient energy transfer and self-absorption significantly limit their light yield. In this study, we developed solvent- and polymer-free CdSe/CdZnS NC films (50-200 mu m thick) and quantitatively evaluated their gamma-ray response and its light yield through single-photoelectron (SPE)-based measurements. The NC films preserved their intrinsic optical characteristics after fabrication and exhibited distinct photopeaks at 59.5 keV (Am-241) and 81.0 keV (Ba-133), achieving a light yield of approximately 3200 +/- 100 photons/MeV with a fast decay time of similar to 20 ns-comparable to reported NC/polymer nanocomposite scintillators. We further investigated solvent effects using NC-doped liquid scintillators, revealing the importance of solvent selection for observing measurable scintillation signals.

Impact of trastuzumab deruxtecan (T-DXd) and brain stereotactic radiosurgery on intracranial control and radionecrosis risk in HER2-positive or -low breast cancer brain metastases

Mon, 01 Jun 2026 00:00:00 GMT

Title: Impact of trastuzumab deruxtecan (T-DXd) and brain stereotactic radiosurgery on intracranial control and radionecrosis risk in HER2-positive or -low breast cancer brain metastases Authors: Chun, Seok-Joo; Kim, Kyubo; Chang, Won Ick; Kim, Yong Bae; Ha Paek, Sun; Lee, Kyung-Hun; Song, Jin-Ho; Hong, Ji Hyun; Lee, Jieun; Il Jang, Won; Kim, Tae Hyun; Shin, Kyung Hwan Abstract: Background While trastuzumab deruxtecan (T-DXd) demonstrates intracranial efficacy, the potential for radionecrosis (RN) when combined with stereotactic radiosurgery (SRS) remains a concern, given the established risk with other antibody-drug conjugates like T-DM1. This study evaluated the safety and efficacy of T-DXd and SRS in patients with HER2-positive or -low breast cancer brain metastases (BCBM). Methods We conducted a multi-center retrospective analysis of 113 patients (461 SRS treatments) treated with SRS and anti-HER2 agents. Patients were stratified into T-DXd(+) (n = 29 patients, 61 treatments) and T-DXd(-) (n = 84 patients, 400 treatments) groups. Endpoints included RN, radionecrosis-free survival (RNFS), and intracranial control outcomes (any intracranial progression, local failure, and distant intracranial metastasis). Results No cases of RN were observed in the T-DXd(+) group, compared with 11 cases in the T-DXd(-) group (p = 0.028). On multivariate analysis, T-DXd(+) status remained significantly associated with improved RNFS (HR 0.31, p = 0.009). In the treatment-level analysis, the 1-year cumulative incidence of RN was 0% for T-DXd(+) versus 4.3% for T-DXd(-) (p = 0.009). Additionally, T-DXd(+) was associated with significantly better 1-year outcomes for any intracranial progression (40% vs. 76%, p < 0.001), local failure (6.6% vs. 29%, p = 0.002), and distant intracranial metastasis (40% vs. 66%, p = 0.009). All efficacy endpoints remained significant on multivariate analysis. Conclusion Combining T-DXd with SRS demonstrated a favorable safety profile without increasing the risk of radionecrosis. Furthermore, this combination was associated with superior intracranial control, encompassing both local and distant outcomes, supporting the potential of T-DXd combined with SRS as an effective and well-tolerated approach for HER2-positive or -low BCBM.

Metastasis-directed radiotherapy for oligometastatic cervical carcinoma: Identifying potential beneficiaries

Fri, 01 May 2026 00:00:00 GMT

Title: Metastasis-directed radiotherapy for oligometastatic cervical carcinoma: Identifying potential beneficiaries Authors: Lee, Won Hee; Park, Sangjoon; Wee, Chan Woo; Kim, Yong Bae; 이원희 Abstract: Background: The role of metastasis-directed radiotherapy (MDRT) in oligometastatic cervical carcinoma (OCC) remains unclear. This study evaluated clinical outcomes of MDRT in patients with OCC and identified prognostic factors associated with survival. Materials and methods: Patients with OCC who received MDRT between 2019 and 2022 were retrospectively reviewed. Eligible patients had <= 5 metastatic lesions treated using stereotactic ablative radiotherapy (SABR), defined as radiotherapy delivered in <= 5 fractions with a fractional dose of >= 5 Gy. Oligometastatic disease was classified according to the ESTRO-EORTC consensus. Radiologic response, patterns of failure, progression-free survival (PFS), overall survival (OS), and treatment-related toxicities were analyzed. Results: A total of 83 patients with 114 temporally independent MDRT courses delivered using SABR were included. Repeat oligorecurrence was the most common oligometastatic subtype, observed in 35 patients. Lymph nodes were the most frequently treated sites (37 patients, 44.6%). Systemic therapy was administered either before and/or after MDRT in 54 patients (65.1%). With a median follow-up of 20 months, the local control rate was 60.8%, and disease progression predominantly occurred outside the treated fields. The 2-year PFS and OS rates were 14.5% and 62.9%, respectively. In multivariable analysis, oligometastatic disease classification and RT response were independently associated with OS. No grade 3 or higher treatment-related toxicities were observed. Conclusion: MDRT using SABR achieved favorable outcomes with minimal toxicity in OCC. Oligometastatic disease classification may assist in selecting appropriate patients for MDRT under multidisciplinary approach. Prospective studies are warranted to validate these findings and to define optimal MDRT strategies.

Evaluating Toxicity and Interaction Outcomes of Systemic Therapy and Stereotactic Ablative Radiation Therapy for Oligometastatic Disease : A Secondary Analysis of the Phase 2 SABR-5 Trial

Fri, 01 May 2026 00:00:00 GMT

Title: Evaluating Toxicity and Interaction Outcomes of Systemic Therapy and Stereotactic Ablative Radiation Therapy for Oligometastatic Disease : A Secondary Analysis of the Phase 2 SABR-5 Trial Authors: Kooyman, Aiden; Chang, Jee Suk; Liu, Mitchell; Jiang, Will; Bergman, Alanah; Schellenberg, Devin; Mou, Benjamin; Alexander, Abraham; Carolan, Hannah; Hsu, Fred; Miller, Stacy; Atrchian, Siavash; Chan, Elisa; Ho, Clement; Mohamed, Islam; Lin, Angela; Berrang, Tanya; Bang, Andrew; Chng, Nick; Matthews, Quinn; Huang, Vicky; Mestrovic, Ante; Hyde, Derek; Lund, Chad; Pai, Howard; Valev, Boris; Lefresne, Shilo; Tyldesley, Scott; Olson, Robert; Baker, Sarah Abstract: Purpose: Although stereotactic ablative radiation therapy (SABR) is known for low toxicity and safety, its combined use with specific systemic therapies requires further investigation. This study aims to evaluate the toxicity of SABR in combination with various systemic therapies. Materials and Methods: A secondary analysis of the SABR-5 trial evaluated grade 2+ and 3+ toxicities post-SABR in patients who had received high-risk or non-high-risk systemic therapies before SABR at 4 predefined intervals: concurrent with SABR, 1 day to 1 week prior, 1 to 2 weeks prior, or 2 to 12 weeks prior. High-risk systemic therapy was a priori defined as drugs that may increase treatment toxicity when delivered in close proximity to SABR. This category encompasses cytotoxic chemotherapy, multitargeted tyrosine kinase inhibitors, CDK 4/6 inhibitors, EGFR inhibitors, anti-VEGF agents, and anti-CTLA-4 agents. Results: Among 380 patients, grade 2+ toxicity rates were 17.3% (35/202) off systemic therapy, 19.2% (19/99) on non-high-risk therapy, and 42.9% (3/7) on high-risk therapy concurrent with SABR. Grade 3+ rates were 3.5% (7/202), 4.0% (4/99), and 28.6% (2/7), respectively. On multivariable analysis, concurrent use of high-risk systemic therapy was associated with a higher risk of grade 3+ toxic effects (OR, 14.88; P = .009). No significant risk was noted when high-risk drugs were used within 1 week, 2 weeks, or 2 to 12 weeks of SABR or with any non-high-risk drugs. Grade 2+ toxic effects associated with concurrent high-risk systemic therapy were primarily bone/pain related. Increased tumor diameter also elevated grade 2+ toxicity risk (per 1 cm increment; G2+ OR, 1.19; P < .001). Conclusion: Concurrent use of high-risk drugs has demonstrated a potential of increased SABR-related toxicity, warranting caution in their concurrent use with SABR. In contrast, combining non-high-risk drugs (eg, hormonal therapy) with SABR did not increase risk. Further research is essential to identify risks associated with this therapeutic combination. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.