Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
56
result(s) for
"Kouloulias, Vassilis"
Sort by:
Lung cancer histology classification from CT images based on radiomics and deep learning models
by
Oikonomopoulos Nikolaos
,
Kelekis Nikolaos
,
Karaiskos Pantelis
in
Adenocarcinoma
,
Artificial neural networks
,
Clinical decision making
2021
Adenocarcinoma (AC) and squamous cell carcinoma (SCC) are frequent reported cases of non-small cell lung cancer (NSCLC), responsible for a large fraction of cancer deaths worldwide. In this study, we aim to investigate the potential of NSCLC histology classification into AC and SCC by applying different feature extraction and classification techniques on pre-treatment CT images. The employed image dataset (102 patients) was taken from the publicly available cancer imaging archive collection (TCIA). We investigated four different families of techniques: (a) radiomics with two classifiers (kNN and SVM), (b) four state-of-the-art convolutional neural networks (CNNs) with transfer learning and fine tuning (Alexnet, ResNet101, Inceptionv3 and InceptionResnetv2), (c) a CNN combined with a long short-term memory (LSTM) network to fuse information about the spatial coherency of tumor’s CT slices, and (d) combinatorial models (LSTM + CNN + radiomics). In addition, the CT images were independently evaluated by two expert radiologists. Our results showed that the best CNN was Inception (accuracy = 0.67, auc = 0.74). LSTM + Inception yielded superior performance than all other methods (accuracy = 0.74, auc = 0.78). Moreover, LSTM + Inception outperformed experts by 7–25% (p < 0.05). The proposed methodology does not require detailed segmentation of the tumor region and it may be used in conjunction with radiological findings to improve clinical decision-making.
Journal Article
Volumetric Modulated Arc Therapy Versus Dynamic Conformal Arc Therapy for Single Isocenter Stereotactic Radiotherapy of Multiple Brain Metastases
2026
Introduction: Stereotactic radiosurgery is a highly precise radiotherapy technique widely used for the management of brain metastases. While VMAT enables highly conformal dose distributions, it is often associated with increased plan complexity and longer delivery times. Optimized dynamic conformal arc therapy (OptDCA) represents a less complex alternative that may achieve comparable dosimetric performance. In this retrospective study, dosimetric quality, deliverability, and plan complexity of VMAT and OptDCA were compared for single-isocenter SRS of multiple brain metastases. Materials and Methods: Thirty patients previously treated with VMAT were randomly selected and replanned using OptDCA with identical beam arrangements. Plan quality was evaluated using the Paddick conformity index, gradient index, target coverage, MUs, and brain V12Gy and V20Gy. Deliverability was assessed using gamma passing rates, and plan complexity was quantified using multiple complexity metrics. Results: VMAT achieved a slightly higher CI (0.72 vs. 0.71) but required a higher number of MUs (5376 vs. 4820), while no significant differences were observed in GI or target coverage. OptDCA demonstrated significantly higher GPR (median 96.95% vs. 91.1%) and consistently lower plan complexity. Significant correlations were observed between GPR and several complexity metrics for both techniques. Conclusion: Overall, OptDCA provides comparable plan quality to VMAT, while offering improved deliverability and reduced complexity, making it a viable alternative technique.
Journal Article
The Impact of Salvage Radiotherapy in Recurrent Endometrial Cancer: A Review Focusing on Early-Stage, Endometrial Cancer Locoregional Relapses
by
Papageorgiou, Georgios
,
Kypraiou, Efrosyni
,
Maragkoudakis, Emmanouil
in
Adjuvants
,
Analysis
,
Cancer
2025
Background/Objectives: Definitive radiotherapy (RT) is a frequently employed salvage option in early-stage, endometrial cancer (EC) loco-regional recurrence patients. Local control (LC) and survival rates are highly variable in the literature. The aim of this review is to assess the impact of modern salvage radiotherapy (SRT) in this group of patients. Methods: A systematic review of the literature was performed, focusing on studies that included EC local recurrence patients receiving SRT after 2000 to reflect advances in radiotherapy techniques. Our report followed the principles as outlined in the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Nine studies were included in our analysis with a total sample size of 648 patients. Conclusions: SRT offers excellent LC rates in this group of patients with minimal ≥ grade 3 toxicity. Salvage rates are limited by the presence of well-known risk factors for loco-regional relapses, with distant control being the primary mode of failure, resulting in lower survival rates. The decision to omit adjuvant RT should be weighed against the anticipated salvage outcomes in case of relapse.
Journal Article
Surface-Guided Radiotherapy: Can We Move on from the Era of Three-Point Markers to the New Era of Thousands of Points?
by
Platoni, Kalliopi
,
Stroubinis, Theodoros
,
Stasinou, Despoina
in
Accuracy
,
Algorithms
,
Automation
2023
The surface-guided radiotherapy (SGRT) technique improves patient positioning with submillimeter accuracy compared with the conventional positioning technique of lasers using three-point tattoos. SGRT provides solutions to considerations that arise from the conventional setup technique, such as variability in tattoo position and the psychological impact of the tattoos. Moreover, SGRT provides monitoring of intrafractional motion. Purpose: This literature review covers the basics of SGRT systems and examines whether SGRT can replace the traditional positioning technique. In addition, it investigates SGRT’s potential in reducing positioning times, factors affecting SGRT accuracy, the effectiveness of live monitoring, and the impact on patient dosage. Materials and Methods: This study focused on papers published from 2016 onward that compared SGRT with the traditional positioning technique and investigated factors affecting SGRT accuracy and effectiveness. Results/Conclusions: SGRT provides the same or better results regarding patient positioning. The implementation of SGRT can reduce overall treatment time. It is an effective technique for detecting intrafraction patient motion, improving treatment accuracy and precision, and creating a safe and comfortable environment for the patient during treatment.
Journal Article
Nanoparticle-Mediated Radiotherapy: Unraveling Dose Enhancement and Apoptotic Responses in Cancer and Normal Cell Lines
by
Platoni, Kalliopi
,
Spyratou, Ellas
,
Havaki, Sophia
in
Apoptosis
,
Biocompatibility
,
Cancer therapies
2023
Cervical cancer remains a pressing global health concern, necessitating advanced therapeutic strategies. Radiotherapy, a fundamental treatment modality, has faced challenges such as targeted dose deposition and radiation exposure to healthy tissues, limiting optimal outcomes. To address these hurdles, nanomaterials, specifically gold nanoparticles (AuNPs), have emerged as a promising avenue. This study delves into the realm of cervical cancer radiotherapy through the meticulous exploration of AuNPs’ impact. Utilizing ex vivo experiments involving cell lines, this research dissected intricate radiobiological interactions. Detailed scrutiny of cell survival curves, dose enhancement factors (DEFs), and apoptosis in both cancer and normal cervical cells revealed profound insights. The outcomes showcased the substantial enhancement of radiation responses in cancer cells following AuNP treatment, resulting in heightened cell death and apoptotic levels. Significantly, the most pronounced effects were observed 24 h post-irradiation, emphasizing the pivotal role of timing in AuNPs’ efficacy. Importantly, AuNPs exhibited targeted precision, selectively impacting cancer cells while preserving normal cells. This study illuminates the potential of AuNPs as potent radiosensitizers in cervical cancer therapy, offering a tailored and efficient approach. Through meticulous ex vivo experimentation, this research expands our comprehension of the complex dynamics between AuNPs and cells, laying the foundation for their optimized clinical utilization.
Journal Article
Markers of Epithelial to Mesenchymal Transition in Association with Survival in Head and Neck Squamous Cell Carcinoma (HNSCC)
by
Rimm, David
,
Burtness, Barbara
,
Zaramboukas, Thomas
in
Analysis
,
Automation
,
Biology and Life Sciences
2014
Elucidating the molecular phenotype of cancers with high metastatic potential will facilitate the development of novel therapeutic approaches to the disease. Gene expression profiles link epithelial to mesenchymal transition (EMT) phenotype with high-risk HNSCC. We sought to determine the role of protein biomarkers of EMT in head and neck squamous carcinoma (HNSC) prognosis.
Protein expression analysis of EGFR, β-catenin and E-cadherin was performed on a cohort of 102 patients with HNSCC recruited between 1992 and 2005 using automated quantitative protein analysis (AQUA). We evaluated associations with clinicopathological parameters and prognosis.
There were 67 patients with primary squamous cell carcinoma of the head and neck in this cohort who met inclusion criteria and for whom we had complete E-cadherin, beta-catenin and EGFR expression data. High E-cadherin expressers had longer 5-year progression-free survival (PFS) compared to those with low E-cadherin (59.7% versus 40.6%, p = 0.04) and overall survival (OS) (69.6% versus 44.3%, p = 0.05). Kaplan-Meier analysis showed that patients with low beta-catenin-expressing tumors trended toward worse 5-year PFS (p = 0.057). High EGFR expressers had inferior OS compared to low EGFR expressers (27.7% vs. 54%, p = 0.029). In the multivariable analysis context, E-cadherin remained an independent predictor of improved OS (HR = 0.204, 95% CI 0.043 to 0.972, p = 0.046) while EGFR trended towards significance for OS.
The putative markers of EMT defined within a panel of HNSCC using AQUA are associated with tumors of poor prognosis.
Journal Article
IFN-Type-I Response and Systemic Immunity in Rectal Adenocarcinoma Patients Treated with Conventional or Hypofractionated Neoadjuvant Radiotherapy
by
Koukourakis, Michael I.
,
Koukourakis, Ioannis M.
,
Xanthopoulou, Erasmia
in
Adenocarcinoma
,
Adenocarcinoma - immunology
,
Adenocarcinoma - pathology
2024
The IFN-type-I pathway is involved in radiotherapy (RT)-mediated immune responses. Large RT fractions have been suggested to potently induce this pathway. Neoadjuvant hypofractionated short-course (scRT) and conventional long-course (lcRT) RT applied for the treatment of locally advanced rectal adenocarcinoma patients provides a unique model to address the immuno-stimulatory properties of RT on a systemic level. We prospectively analyzed the IFNβ plasma levels and lymphocyte counts (LCs) of rectal adenocarcinoma patients before and after treatment with scRT (n = 22) and lcRT (n = 40). Flow cytometry was conducted to assess the effects on lymphocytic subpopulations in a subset of 20 patients. A statistically significant increase in the post-RT IFNβ plasma levels was noted in patients undergoing scRT (p = 0.004). Improved pathological tumor regression was associated with elevated post-RT IFNβ levels (p = 0.003). Although all patients experienced substantial lymphopenia after treatment, the post-RT LC of patients treated with scRT were significantly higher compared to lcRT (p = 0.001). Patients undergoing scRT displayed significantly lower percentages of regulatory CD4+/CD25+ T-cells after therapy (p = 0.02). scRT enables effective stimulation of the IFN-type-I pathway on a systemic level and confers decreased lymphocytic cytotoxicity and limited regulatory T-cell activation compared to lcRT, supporting its increasing role in immuno-RT trials.
Journal Article
Adapting Amidst Vulnerability: An Interpretative Phenomenological Analysis Study on Gay Men Living With HIV
by
Thanasko, Florian
,
Parpa, Efi
,
Nikoloudi, Maria
in
Adaptation
,
Chronic illnesses
,
Data analysis
2024
HIV represents a \"biographical disruption\", interrupting the continuity of life and fostering a sense of vulnerability. The transition of HIV into a chronic condition, coupled with extended life expectancy, necessitates significant lifestyle adjustments, making adaptation and navigation through uncertainties essential.
Interpretative phenomenological analysis was used to investigate the lived experiences and adaptation processes of gay men in Greece who are living with HIV. Semi-structured interviews were conducted with seven HIV-positive gay men, recruited from two Greek NGOs that support individuals living with HIV. Investigator triangulation was used to interpret textual material, heightening credibility and reducing bias, thereby enhancing the findings' reliability.
The analysis identified a superordinate theme, \"Being Vulnerable Enough: Negotiating Uncertainties and Adapting in the HIV Experience\", which encompasses three themes: \"The Moment of Division: Fear, Uncertainty, and Vulnerability after an HIV Diagnosis\", \"Grief and Negotiation: Navigating Daily Life Through the Lens of Loss\", and \"Reclaiming Self: Shaping 'My HIV Identity' to Fit on My Terms\".
The initial shock of HIV diagnosis introduces a sense of vulnerability, with participants confronting fear, despair, and grief over the loss of health and the disruption of their anticipated life flow. Being vulnerable enough enables individuals to adapt to life with HIV by managing uncertainties through creating certainties with small daily decisions, in a non-linear, ongoing process of negotiation and reassessment, without the need to eliminate all uncertainties.
Journal Article
Unravelling Quality of Life for Head and Neck Cancer Patients after VMAT Radiation Therapy: Insights from Toxicity, Dosimetry and Symptoms Correlation
by
Platoni, Kalliopi
,
Kougioumtzopoulou, Andromachi
,
Patatoukas, Georgios
in
Body image
,
Cancer therapies
,
Clinical outcomes
2024
(1) Background: Head and neck cancer treatment, including advanced techniques like Volumetric Modulated Arc Therapy (VMAT), presents challenges for maintaining patient quality of life (QoL). Thus, thoroughly investigating how radiation therapy (RT) affects patients has been proved essential. Derived by that, this study aims to understand the complex interactions between not only RT and QoL but also symptom severity, and treatment-related toxicities in three distinct time points of patient’s treatment; (2) Methods: To achieve that, EORTC-QLQ-C30 and EORTC QLQ-H&N35 questionnaires were used in combination with EORTC_RTOG scoring criteria and Spearman’s rho statistical analysis for 74 patients with cancer undergoing VMAT radiation therapy; (3) Results: The results revealed a significant improvement in the Overall Health Index post-treatment, indicating a temporary decline during therapy followed by subsequent recovery, often surpassing pre-treatment QoL levels. Concurrently a reduction in symptomatology was observed, notably in pain, swallowing difficulties, and dry mouth, aligning with prior research indicating decreased symptom burden post-treatment. However, Spearman’s correlation coefficient analysis at two distinct time points during therapy uncovered varying degrees of correlation between dosimetric data at Organs at Risk (OARs) and reported symptoms, highlighting potential limitations in using QoL questionnaires as sole indicators of treatment efficacy. Our investigation into the correlation between dosimetric data, toxicity, and symptoms focused on the relationship between radiation doses and oral mucositis levels, a common toxicity in head and neck cancer patients. Significant associations were identified between toxicity levels and dosimetric parameters, particularly with OARs such as the parotid glands, oral cavity, and swallowing muscles, underlining the utility of the EORTC method as a reliable toxicity assessment tool; (4) Conclusions: To summarize, current research attempts to underscore the importance of refining QoL assessments for enhanced patient care. The integration of dosimetric data, symptom severity, and treatment-related toxicities in the QoL outcomes of head and neck cancer patients undergoing VMAT radiation therapy, can lead towards the optimization of treatment strategies and the improvement of patient outcomes in future patient-centered radiation therapy practices.
Journal Article
Stereotactic Arrhythmia Radioablation as a Novel Treatment Approach for Cardiac Arrhythmias: Facts and Limitations
by
Platoni, Kalliopi
,
Vrachatis, Dimitrios
,
Tousoulis, Dimitris
in
Ablation
,
Arrhythmia
,
atrial fibrillation
2021
Stereotactic ablative radiotherapy (SABR) is highly focused radiation therapy that targets well-demarcated, limited-volume malignant or benign tumors with high accuracy and precision using image guidance. Stereotactic arrhythmia radioablation (STAR) applies SABR to treat cardiac arrhythmias, including ventricular tachycardia (VT) and atrial fibrillation (AF), and has recently been a focus in research. Clinical studies have demonstrated electrophysiologic conduction blockade and histologic fibrosis after STAR, which provides a proof of principle for its potential for treating arrhythmias. This review will present the basic STAR principles, available clinical study outcomes, and how the technique has evolved since the first pre-clinical study. In addition to the clinical workflow, focus will be given on the process for stereotactic radiotherapy Quality Assurance (QA) tests, as well as the need for establishing a standardized QA protocol. Future implications and potential courses of research will also be discussed.
Journal Article