GEORGE DIMITRIOS PATATOUKAS

Dr. GEORGE DIMITRIOS PATATOUKAS


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 November 2023 in Biomolecules
Verified
Journal Article
Open access
PDF file
Maria Anthi KouriMaria Anthi Kouri
Maria Anthi Kouri
Ellas SpyratouEllas Spyratou
Ellas Spyratou
MKMaria-Eleni Kalkou
Maria-Eleni Kalkou
GPGEORGE DIMITRIOS PATATOUKAS
GEORGE DIMITRIOS PATATOUKAS
EAEvangelia Angelopoulou
Evangelia Angelopoulou
Efstathios P. EfstathopoulosEfstathios P. Efstathopoulos
Efstathios P. Efstathopoulos
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.

2 March 2023 in Biomedicines
Verified
Journal Article
Open access
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AFAnna-Maria Fanou
Anna-Maria Fanou
GPGEORGE DIMITRIOS PATATOUKAS
GEORGE DIMITRIOS PATATOUKAS
MCMarina Theofanis Chalkia
Marina Theofanis Chalkia
NKNikolaos Kollaros
Nikolaos Kollaros
AKAndromachi Kougioumtzopoulou
Andromachi Kougioumtzopoulou
Kalliopi-Pola PlatoniKalliopi-Pola Platoni
Kalliopi-Pola Platoni
The aim of this study was to evaluate knowledge-based treatment planning (KBP) models in terms of their dosimetry and deliverability and to investigate their clinical benefits. Three H&N KBP models were built utilizing RapidPlan™, based on the dose prescription, which is given according to the planning target volume (PTV). The training set for each model consisted of 43 clinically acceptable volumetric modulated arc therapy (VMAT) plans. Model quality was assessed and compared to the delivered treatment plans using the homogeneity index (HI), conformity index (CI), structure dose difference (PTV, organ at risk—OAR), monitor units, MU factor, and complexity index. Model deliverability was assessed through a patient-specific quality assurance (PSQA) gamma index-based analysis. The dosimetric assessment showed better OAR sparing for the RapidPlan™ plans and for the low- and high-risk PTV, and the HI, and CI were comparable between the clinical and RapidPlan™ plans, while for the intermediate-risk PTV, CI was better for clinical plans. The 2D gamma passing rates for RapidPlan™ plans were similar or better than the clinical ones using the 3%/3 mm gamma-index criterion. Monitor units, the MU factors, and complexity indices were found to be comparable between RapidPlan™ and the clinical plans. Knowledge-based treatment plans can be safely adapted into clinical routines, providing improved plan quality in a time efficient way while minimizing user variability.

6 June 2024 in Clinics and Practice
Verified
Journal Article
Open access
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PKPanagiota Kiafi
Panagiota Kiafi
Maria Anthi KouriMaria Anthi Kouri
Maria Anthi Kouri
GPGEORGE DIMITRIOS PATATOUKAS
GEORGE DIMITRIOS PATATOUKAS
AKAndromachi Kougioumtzopoulou
Andromachi Kougioumtzopoulou
MCMarina Theofanis Chalkia
Marina Theofanis Chalkia
Kalliopi-Pola PlatoniKalliopi-Pola Platoni
Kalliopi-Pola Platoni
(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.

18 March 2024 in Cancers
Verified
Journal Article
Open access
PDF file
AKAndromachi Kougioumtzopoulou
Andromachi Kougioumtzopoulou
NSNIKOLAOS SYRIGOS
NIKOLAOS SYRIGOS
AZAnna Zygogianni
Anna Zygogianni
IGIoannis Georgakopoulos
Ioannis Georgakopoulos
Kalliopi-Pola PlatoniKalliopi-Pola Platoni
Kalliopi-Pola Platoni
Vassilis KoulouliasVassilis Kouloulias
Vassilis Kouloulias
Background: Moderate hypofractionated radiotherapy (MHRT) has emerged as the preferred treatment modality for localized prostate cancer based on randomized controlled studies regarding efficacy and toxicity using contemporary radiotherapy techniques. In the setting of MHRT, available data on dosimetric parameters and late rectal toxicity are limited. Aim: To present the effects of MHRT on late rectal toxicity while conducting an extensive dosimetric analysis in conjunction with rectoscopy results. Methods: This is a prospective study including patients with intermediate-risk prostate adenocarcinoma. All patients were treated with MHRT 44 Gy in 16 fractions to the seminal vesicles and to the prostate, followed by a sequential boost to the prostate alone of 16.5 Gy in 6 fractions delivered with three-dimensional conformal radiation therapy (3DCRT). Acute and late toxicity were assessed. Endoscopy was performed at baseline, every 3 months post-therapy for the first year, and every 6 months for the year after. The Vienna Rectoscopy Score (VRS) was used to assess rectal mucosal injury related to radiotherapy. Dosimetric analysis for the rectum, rectal wall, and its subsegments (upper, mid, and low 1/3) was performed. Results: Between September 2015 and December 2019, 20 patients enrolled. Grade 1 late gastrointestinal toxicity occurred in 10% of the patients, whereas 5% had a grade ≥2. Twelve months post radiotherapy: 4 (20%) patients had VRS 1; 2 (10%) patients had VRS 2; 1(5%) patient had VRS 3. 24 months post radiotherapy, VRS 1 was observed in 4 patients (20%) and VRS 2 in 3 (15%) patients. The dosimetric analysis demonstrated noticeable variations between the rectum, rectal wall, and rectal wall subsegments. The dosimetric analysis of the rectum, rectal wall, and its mid and low segments with respect to rectoscopy findings showed that the higher dose endpoints V52.17Gy and V56.52Gy are associated with rectal mucosal injury. Conclusions: A thorough delineation of the rectal wall and its subsegments, together with the dosimetric analysis of these structures, may reduce late rectal toxicity. Dosimetric parameters such as V52.17Gy and V56.52Gy were identified to have a significant impact on rectal mucosal injury; additional dose endpoint validation and its relation to late GI toxicity is needed.

17 September 2026 in Cancers
Verified
Journal Article
Open access
PDF file
Maria Anthi KouriMaria Anthi Kouri
Maria Anthi Kouri
MKMaria-Eleni Kalkou
Maria-Eleni Kalkou
Kalliopi-Pola PlatoniKalliopi-Pola Platoni
Kalliopi-Pola Platoni
NKNikolaos Kollaros
Nikolaos Kollaros
KZKyveli Zourari
Kyveli Zourari
Efstathios P. EfstathopoulosEfstathios P. Efstathopoulos
Efstathios P. Efstathopoulos
Background/Objectives: Cervical cancer treatment relies heavily on high-dose-rate (HDR) 192Ir brachytherapy; however, therapeutic efficacy remains limited by tumor radioresistance and the inability to escalate dose without increasing toxicity to surrounding healthy tissues. The present study investigates the potential of gold nanoparticles (AuNPs) to enhance radiosensitivity under clinically relevant 192Ir brachytherapy conditions through the combined action of physical dose amplification and radiobiological modulation. Particular emphasis is placed on the unique radiophysical interactions generated by the mixed gamma and secondary beta emissions of 192Ir, which, in the presence of high atomic number nanoparticles, promote localized photoelectric absorption and the emission of low-range secondary electrons, including Auger electrons. The study further aims to determine how AuNPs size and post-irradiation temporal evolution influence radiation-induced cytotoxicity and apoptosis in cervical cancer cell lines, thereby providing a biologically representative model of nanoparticle-assisted brachytherapy. Methods: Clonogenic survival, dose enhancement factor (DEF), and apoptosis were evaluated following irradiation in the presence of 10 nm and 50 nm AuNPs in two independent biological experiments (n = 2). Results: A clear dose-dependent reduction in survival fraction and increase in apoptosis were observed in nanoparticle-treated groups compared with irradiation alone. Radiosensitization demonstrated strong size dependence, with 50 nm AuNPs producing the greatest enhancement, a finding that may reflect size-dependent differences in cellular internalization, intracellular distribution, and nanoscale energy deposition previously established in AuNP studies. Importantly, biological effects intensified at later post-irradiation intervals, demonstrating a sustained temporal evolution of the radiobiological response beyond the initial irradiation event, potentially involving oxidative and other delayed cellular stress mechanisms described in AuNP radiosensitization. Conclusions: These findings demonstrate the capacity of AuNPs to enhance the radiobiological response of cervical cancer cells to 192Ir brachytherapy and identify nanoparticle size and post-irradiation time as important determinants of this effect. They therefore support AuNP-assisted brachytherapy as a promising strategy for further development toward biologically optimized radiotherapy capable of improving tumor response without escalation of the prescribed radiation dose.

8 September 2026 in Cancers
Verified
Journal Article
Open access
PDF file
GNGeorgios Nikiforos Ntoumas
Georgios Nikiforos Ntoumas
DDDimitra Desse
Dimitra Desse
AZAnna Zygogianni
Anna Zygogianni
AKAndromachi Kougioumtzopoulou
Andromachi Kougioumtzopoulou
DADimitrios Alexandros Angelakis
Dimitrios Alexandros Angelakis
Kalliopi-Pola PlatoniKalliopi-Pola Platoni
Kalliopi-Pola Platoni
Background/Objectives: Proton therapy provides superior dose conformity and better normal tissue sparing than conventional radiotherapy but is limited by its relatively low relative biological effectiveness (RBE). Nanoparticles have emerged as promising proton radiosensitizers capable of enhancing physical dose deposition and biological responses. Methods: A narrative literature review was conducted using PubMed, Scopus, Web of Science, and Google Scholar. Results: Gold nanoparticles were the most extensively studied radiosensitizers, while platinum, gadolinium, hafnium oxide, titanium dioxide, iron oxide, and other nanoparticles also demonstrated promising radiosensitizing effects. Evidence indicates that nanoparticles enhance local dose deposition, increase LET and ROS production, promote DNA damage, and improve tumor control. Conclusions: Nanoparticle-assisted proton therapy represents a promising strategy for improving cancer treatment by increasing therapeutic efficacy while preserving healthy tissues. Although preclinical studies demonstrate significant improvements in therapeutic efficacy, challenges related to tumor targeting, biodistribution, safety, and clinical validation remain. Further research is required to facilitate clinical implementation.