Tumor recurrences or new tumors may develop after irradiation of local lesion(s) in the brain, and additional radiotherapy treatments are often needed for previously treated patients. It is critical to re-establish the dose distributions delivered during the previous treatment in the current patient geometry, so that the previous dose distributions can be accurately taken into consideration in the design of the current treatment plan. The difficulty in re-establishing the previous treatment dose distributions in the current patient geometry arises from the fact that the patient position at the time of reirradiation is different from that at the previous treatment session. Simple re-entry of the previous isocenter coordinates, gantry, and couch and collimator angles into the new treatment plan would result in incorrect beam orientations relative to the new patient anatomy, and therefore incorrect display of the previous dose distributions on the current patient anatomy. To address this issue, a method has been developed so that the previous dose distributions can be accurately re-established in the framework of the current brain treatment. The method involves 3 matrix transformations: (1) transformation of beams from machine coordinate system to patient coordinate system in the previous treatment; (2) transformation of beams from patient coordinate system in the previous treatment to patient coordinate system in the current treatment; and (3) transformation of beams from patient coordinate system in the current treatment to machine coordinate system. The transformation matrices used in the second transformation are determined by registration using a mutual information-based algorithm with which the old and new computed tomography (CT) scan sets are registered automatically without human interpretation. A series of transformation matrices are derived to calculate the isocenter coordinates, the gantry, couch, and collimator angles of the beams for the previous treatment in the current patient geometry, and the previous dose distributions are re-established on the current CT images. The method has been proven to be successful and robust.
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http://dx.doi.org/10.1016/j.meddos.2003.09.004 | DOI Listing |
BMC Cancer
January 2025
Department of Radiation Oncology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, P. R. China.
Introduction: The core objective of this study was to precisely locate metastatic lymph nodes, identify potential areas in nasopharyngeal carcinoma patients that may not require radiotherapy, and propose a hypothesis for reduced target volume radiotherapy on the basis of these findings. Ultimately, we reassessed the differences in dosimetry of organs at risk (OARs) between reduced target volume (reduced CTV2) radiotherapy and standard radiotherapy.
Methods And Materials: A total of 209 patients participated in the study.
Methods Cell Biol
January 2025
T Cell Lymphoma Group, Josep Carreras Leukaemia Research Institute, Barcelona, Spain. Electronic address:
T cell lymphoma constitutes a complex group of diseases, characterized by heterogeneous molecular features and clinical symptoms, and a dismal outcome no matter the therapeutic strategy chosen. In an attempt to improve patients' survival chances, treatment combinations (chemotherapy, radiotherapy, immunotherapy, gene therapy and thermotherapy) have been tested for their synergistic effects that may dramatically improve outcomes and reduce the side effects of each single modality treatment when therapeutic effects add up while side effects are distributed. In this context, nanoscale drug delivery agents have been developed and exploited to enhance the release of drugs in the treatment of several diseases, showing potential benefits in terms of pharmaceutical flexibility, selectivity, dose reduction and minimization of adverse effects.
View Article and Find Full Text PDFChemosphere
January 2025
Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Instituto de Investigaciones en Ciencias de La Salud (INICSA), Córdoba, Argentina; Universidad Nacional de Córdoba, Facultad de Ciencias Médicas, Centro de Microscopía Electrónica. Córdoba, Argentina. Electronic address:
DEHP is a prevalent phthalate with wide industrial applications and well-documented endocrine-disrupting effects, including the potential disruption of AR signaling in different tissues. The present study aimed to investigate the effects of gestational and lactational exposure to environmentally relevant DEHP concentrations on AR expression and subcellular localization in the pituitary gland, the master endocrine organ, with a focus on gonadotroph cells by in vivo and in vitro approaches. After DEHP exposure during gestation and lactation, a sex-specific modulation was detected in AR-positive pituitary cells and AR protein expression as assessed through flow cytometry and western blot.
View Article and Find Full Text PDFComput Biol Med
January 2025
Department of Pharmacy and Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea; Department of Pharmaceutical Medicine and Regulatory Science, Yonsei University, Incheon, Republic of Korea; Graduate Program of Industrial Pharmaceutical Science, Yonsei University, Incheon, Republic of Korea; Department of Integrative Biotechnology, Yonsei University, Incheon, Republic of Korea. Electronic address:
Background: Erlotinib is a potent first-generation epidermal growth factor receptor tyrosine kinase inhibitor. Due to its proximity to the upper limit of tolerability, dose adjustments are often necessary to manage potential adverse reactions resulting from its pharmacokinetic (PK) variability.
Methods: Population PK studies of erlotinib were identified using PubMed databases.
Naunyn Schmiedebergs Arch Pharmacol
January 2025
Department of Organ Transplantation, The Second Affiliated Hospital of Nanchang University, Minde Road No. 1, Nanchang, 330006, Jiangxi, China.
Multimorbidity, therapeutic complexity, and polypharmacy, which greatly increases the risk of drug-drug interactions (DDIs) and adverse medical outcomes, have become important and growing challenges in clinical practice. Statins are frequently prescribed to manage post-transplant dyslipidemia and reduce overall cardiovascular risk in solid organ transplant recipients. This study aimed to determine whether rosuvastatin has significant DDIs with tacrolimus (the first-line immunosuppressant) and to evaluate the risk of hepatotoxicity associated with concomitant therapy.
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