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1.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791289

RESUMO

EZH2 (Enhancer of zeste homolog 2) promotes tumor growth and survival through numerous mechanisms and is a promising target for novel therapeutic approaches. We aimed to characterize the expression of EZH2 in the tumors of young head-and-neck squamous cell cancer (HNSCC) patients in comparison with the general HNSCC patient population. We used formalin-fixed, paraffin-embedded tissue blocks from 68 random young HNSCC patients (≤39 years, median age: 36 years; diagnosed between 2000 and 2018), which were compared with the samples of 58 age- and gender-matched general HNSCC subjects (median age: 62 years; all diagnosed in the year 2014). EZH2 and p53 expression of the tumors was detected using immunohistochemical staining. Lower EZH2 expression was found to be characteristic of the tumors of young HNSCC patients as opposed to the general population (median EZH2 staining intensity: 1 vs. 1.5 respectively, p < 0.001; median fraction of EZH2 positive tumor cells: 40% vs. 60%, respectively, p = 0.003, Mann-Whitney). Cox analysis identified a more advanced T status (T3-4 vs. T1-2), a positive nodal status, and alcohol consumption, but neither intratumoral EZH2 nor p53 were identified as predictors of mortality in the young patient group. The lower EZH2 expression of young HNSCC patients' tumors discourages speculations of a more malignant phenotype of early-onset tumors and suggests the dominant role of patient characteristics. Furthermore, our results might indicate the possibility of an altered efficacy of the novel anti-EZH2 therapies in this patient subgroup.


Assuntos
Biomarcadores Tumorais , Proteína Potenciadora do Homólogo 2 de Zeste , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Proteína Supressora de Tumor p53/metabolismo
2.
Eur J Haematol ; 111(2): 254-262, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37194391

RESUMO

BACKGROUND: FA patients are hypersensitive to preconditioning of bone marrow transplantation. OBJECTIVE: Assessment of the power of mitomycin C (MMC) test to assign FA patients. METHODS: We analysed 195 patients with hematological disorders using spontaneous and two types of chromosomal breakage tests (MMC and bleomycin). In case of presumed Ataxia telangiectasia (AT), patients' blood was irradiated in vitro to determine the radiosensitivity of the patients. RESULTS: Seven patients were diagnosed as having FA. The number of spontaneous chromosomal aberrations was significantly higher in FA patients than in aplastic anemia (AA) patients including chromatid breaks, exchanges, total aberrations, aberrant cells. MMC-induced ≥10 break/cell was 83.9 ± 11.4% in FA patients and 1.94 ± 0.41% in AA patients (p < .0001). The difference in bleomycin-induced breaks/cell was also significant: 2.01 ± 0.25 (FA) versus 1.30 ± 0.10 (AA) (p = .019). Seven patients showed increased radiation sensitivity. Both dicentric + ring, and total aberrations were significantly higher at 3 and 6 Gy compared to controls. CONCLUSIONS: MMC and Bleomycin tests together proved to be more informative than MMC test alone for the diagnostic classification of AA patients, while in vitro irradiation tests could help detect radiosensitive-as such, individuals with AT.


Assuntos
Anemia Aplástica , Anemia de Fanconi , Humanos , Anemia Aplástica/etiologia , Anemia Aplástica/genética , Anemia de Fanconi/complicações , Anemia de Fanconi/diagnóstico , Anemia de Fanconi/genética , Quebra Cromossômica , Diagnóstico Diferencial , Mitomicina , Bleomicina
3.
Strahlenther Onkol ; 198(2): 93-109, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34724086

RESUMO

Brachytherapy (BT) has long been used for successful treatment of various tumour entities, including prostate, breast and gynaecological cancer. However, particularly due to advances in modern external beam techniques such as intensity-modulated radiotherapy (IMRT), volume modulated arc therapy (VMAT) and stereotactic body radiotherapy (SBRT), there are concerns about its future. Based on a comprehensive literature review, this article aims to summarize the role of BT in cancer treatment and highlight its particular dosimetric advantages. The authors conclude that image-guided BT supported by inverse dose planning will successfully compete with high-tech EBRT in the future and continue to serve as a valuable modality for cancer treatment.


Assuntos
Braquiterapia , Radioterapia de Intensidade Modulada , Braquiterapia/métodos , Humanos , Masculino , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
4.
Strahlenther Onkol ; 198(9): 812-819, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35157100

RESUMO

PURPOSE: To describe the results of treating tongue cancer patients with single postoperative interstitial, high-dose-rate (HDR) brachytherapy (BT) after resection. METHODS: Between January 1998 and April 2019, 45 patients with squamous cell histology, stage T1-2N0-1M0 tongue tumours were treated by surgery followed by a single HDR BT in case of negative prognostic factors (close or positive surgical margin, lymphovascular and/or perineural invasion). The average dose was 29 Gy (range: 10-45 Gy) and rigid metal needles were used in 11 (24%) and flexible plastic catheters in 34 cases (76%). Survival parameters, toxicities and the prognostic factors influencing survival were analysed. RESULTS: During a mean follow-up of 103 months (range: 16-260 months) for surviving patients, the 10-year local and regional control (LC, RC), overall survival (OS), and disease-specific survival (DSS) probabilities were 85, 73, 34 and 63%, respectively. The incidence of local grade 1, 2 and 3 mucositis was 23, 73 and 4%, respectively. As a serious (grade 4), late side effect, soft tissue necrosis developed in 3 cases (7%). In a univariate analysis, there was a significant correlation between lymphovascular invasion and RC (p = 0.0118) as well as cervical recurrence and DSS (p < 0.0001). CONCLUSION: Sole postoperative HDR brachytherapy can be an effective method in case of negative prognostic factors in the treatment of early, resectable tongue tumours. Comparing the results of patients treated with postoperative BT to those who were managed with surgery or BT alone known from the literature, a slightly more favourable LC can be achieved with the combination therapy, demonstrating the potential compensating effect of BT on adverse prognostic factors, while the developing severe, grade 4 toxicity rate remains low.


Assuntos
Braquiterapia , Neoplasias da Língua , Braquiterapia/métodos , Terapia Combinada , Humanos , Margens de Excisão , Dosagem Radioterapêutica , Estudos Retrospectivos , Neoplasias da Língua/radioterapia , Neoplasias da Língua/cirurgia
5.
Rep Pract Oncol Radiother ; 27(1): 152-160, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402040

RESUMO

Background: The purpose of the study was to dosimetrically compare multicatheter interstitial brachytherapy (MIBT) and stereotactic radiotherapy with CyberKnife (CK) for accelerated partial breast irradiation with special focus on dose to organs at risk (OARs). Materials and methods: Treatment plans of thirty-one patients treated with MIBT were selected and additional CK plans were created on the same CT images. The OARs included ipsilateral non-target and contralateral breast, ipsilateral and contralateral lung, skin, ribs, and heart for left sided cases. The fractionation was identical (4 × 6.25 Gy). Dose-volume parameters were calculated for both techniques and compared. Results: The D90 of the PTV for MIBT and CK were similar (102.4% vs. 103.6%, p = 0.0654), but in COIN the MIBT achieved lower value (0.75 vs. 0.91, p < 0.001). Regarding the V100 parameter of non-target breast CK performed slightly better than MIBT (V100: 1.1% vs. 1.6%), but for V90, V50 and V25 MIBT resulted in less dose. Every examined parameter of ipsilateral lung, skin, ribs and contralateral lung was significantly smaller for MIBT than for CK. Protection of the heart was slightly better with MIBT, but only the difference of D2cm3 was statistically significant (17.3% vs. 20.4%, p = 0.0311). There were no significant differences among the dose-volume parameters of the contralateral breast. Conclusion: The target volume can be properly irradiated by both techniques with high conformity and similar dose to the OARs. MIBT provides more advantageous plans than CK, except for dose conformity and the dosimetry of the heart and contralateral breast. More studies are needed to analyze whether these dosimetrical findings have clinical significance.

6.
Magy Onkol ; 62(3): 145-152, 2018 Sep 26.
Artigo em Húngaro | MEDLINE | ID: mdl-30256880

RESUMO

The incidence of oropharyngeal cancers caused by human papillomavirus rises sharply. They are characterized by very good therapeutic response, including radiosensitivity, as is demonstrated by the results of several retrospective analyses. In the following review publications related to this topic are introduced, (radio)biological causes of radiosensitivity are explored and the role of surgical, chemo- and biological therapeutic methods of these types of tumors are discussed with the aim to better understand their different behavior. Taking into account the younger age and better general condition of patients as well as the tumor radiosensitivity it is recommended to override the current therapeutic guidelines in respect of the doses and treatment methods primarily in order to reduce therapeutic complications. Currently several randomized trials on this subject are in progress.


Assuntos
Neoplasias Orofaríngeas/terapia , Neoplasias Orofaríngeas/virologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/terapia , Humanos , Neoplasias Orofaríngeas/radioterapia , Infecções por Papillomavirus/virologia , Tolerância a Radiação , Estudos Retrospectivos
7.
Magy Onkol ; 62(3): 180-185, 2018 Sep 26.
Artigo em Húngaro | MEDLINE | ID: mdl-30256885

RESUMO

The treatment of squamous cell carcinoma of the head and neck is multimodal, including surgery, chemotherapy, and radiotherapy, or the combination of those. Though aggressive treatment results in complete tumor remission in many patients even in locally advanced stages, unfortunately local relapse is not uncommon. For patients not candidate for salvage surgery, chemotherapy and conventional fractionated external beam irradiation can be applied. However, for patients previously treated with full-dose radiotherapy, the deliverable reirradiation dose is limited, considering the elevated risk of toxicity caused by cumulative doses. CyberKnife is a highly conformal radiosurgical technology which can successfully treat this subset of patients. In addition, it can be applied for hardly resectable rare tumors of the skull base and the head and neck region like chordoma, chondrosarcoma and paragangliomas. The CyberKnife stereotacic radiosurgery technology is now available in Hungary, in the National Institute of Oncology.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Radiocirurgia/métodos , Carcinoma de Células Escamosas/cirurgia , Humanos , Hungria , Recidiva Local de Neoplasia/cirurgia
8.
Magy Onkol ; 62(3): 159-173, 2018 Sep 26.
Artigo em Húngaro | MEDLINE | ID: mdl-30256882

RESUMO

Most head and neck cancer patients are treated with combined modalities such as surgery, radiotherapy (RT), chemotherapy (ChT). Concurrent chemo-radiation has improved treatment outcomes with increased toxic effects. Reactions after RT are divided into early and late changes. Early reactions are seen during the course of therapy or within 3 months; these are reversible in most cases. Late complications are observed 3 months to years after RT and they are generally irreversible. As typical late reaction radiation induced necrosis may occur in soft tissues, cartilage, bones and brain. Tumor recurrence and post-radiation necrosis typically appear at the same time, within 2-3 years after RT; the differentiation may be difficult. Computed tomography (CT) and magnetic resonance imaging (MRI) have become the gold standards not only for staging and assessing tumor response, but also to evaluate posttreatment status, to distinguish residual or recurrent tumor and RT complications. Using baseline CT or MRI between 2-3 months after treatment and performing standard follow-up imaging with strict clinical follow-up are required to establish early salvage treatment.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Terapia de Salvação
9.
Strahlenther Onkol ; 193(6): 452-458, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28154882

RESUMO

PURPOSE: To present the feasibility and complications of transperineal fiducial marker implantation in prostate cancer patients undergoing image-guided radiotherapy (IGRT) METHODS AND MATERIALS: Between November 2011 and April 2016, three radiopaque, gold-plated markers were transperineally implanted into the prostate of 300 patients under transrectal ultrasound guidance and with local anaesthesia. A week after the procedure patients filled in a questionnaire regarding pain, dysuria, urinary frequency, nocturia, rectal bleeding, hematuria, hematospermia or fever symptoms caused by the implantation. Pain was scored on a 1-10 scale, where score 1 meant very weak and score 10 meant unbearable pain. The implanted gold markers were used for daily verification and online correction of patients' setup during IGRT. RESULTS: Based on the questionnaires no patient experienced fever, infection, dysuria or rectal bleeding after implantation. Among the 300 patients, 12 (4%) had hematospermia, 43 (14%) hematuria, which lasted for an average of 3.4 and 1.8 days, respectively. The average pain score was 4.6 (range 0-9). Of 300 patients 87 (29%) felt any pain after the intervention, which took an average of 1.5 days. None of the patients needed analgesics after implantation. Overall, 105 patients (35%) reported less, 80 patients (27%) more, and 94 patients (31%) equal amount of pain during marker implantation compared to biopsy. The 21 patients who had a biopsy performed under general anesthesia did not answer this question. CONCLUSION: Transperineal gold marker implantation under local anesthesia was well tolerated. Complications were limited; rate and frequency of perioperative pain was comparable to the pain caused by biopsy. The method can be performed safely in clinical practice.


Assuntos
Marcadores Fiduciais , Ouro , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos de Viabilidade , Marcadores Fiduciais/efeitos adversos , Hematúria/etiologia , Hemospermia/etiologia , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Medição da Dor , Períneo , Estudos Prospectivos , Planejamento da Radioterapia Assistida por Computador/métodos , Inquéritos e Questionários , Tomografia Computadorizada por Raios X
10.
Strahlenther Onkol ; 193(1): 70-79, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27872946

RESUMO

PURPOSE: To report 3­year results of accelerated partial breast irradiation (APBI) using image-guided intensity-modulated radiotherapy (IG-IMRT) following breast conserving surgery (BCS) for low-risk early invasive breast cancer. PATIENTS AND METHODS: Between July 2011 and March 2014, 60 patients with low-risk early invasive breast cancer underwent BCS and were enrolled in this phase II prospective study. The total dose was 36.9 Gy (9 fractions of 4.1 Gy, two fractions/day). Patient setup errors were detected in LAT, LONG and VERT directions. Local tumour control, survival results, early and late side effects and cosmetic outcome were assessed. RESULTS: At a median follow-up of 39 months, all patients were alive and neither locoregional nor distant failure occurred. One contralateral breast cancer and two new primary malignancies outside the breast were observed. No grade (G) 3-4 acute toxicity was detected. G1 and G2 erythema occurred in 21 (35%) and 2 (3.3%) patients, respectively; while G1 oedema was observed in 23 (38.8%) cases. G1 and G2 pain was reported by 6 (10%) and 2 (3.3%) patients, respectively. Among the late radiation side effects, G1 pigmentation or telangiectasia, G1 fibrosis and G1 asymptomatic fat necrosis occurred in 10 (16.7%), 7 (11.7%) and 3 (5%) patients, respectively. No ≥ G2 late toxicity was detected. Cosmetic outcome was excellent in 43 (71.7%) and good in 17 (28.3%) patients. CONCLUSION: IG-IMRT is a reproducible and feasible technique for delivery of external beam APBI following BCS for treatment of low-risk, early-stage invasive breast carcinoma. In order to avoid toxicity, image guidance performed before each radiation fraction is necessary to minimize the PTV. Three-year results are promising, early and late radiation side-effects are minimal, and cosmetic results are excellent to good.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Fracionamento da Dose de Radiação , Mastectomia Segmentar/mortalidade , Lesões por Radiação/mortalidade , Radioterapia Conformacional/mortalidade , Adulto , Idoso , Terapia Combinada/mortalidade , Terapia Combinada/estatística & dados numéricos , Feminino , Humanos , Hungria/epidemiologia , Estudos Longitudinais , Mastectomia Segmentar/estatística & dados numéricos , Pessoa de Meia-Idade , Prevalência , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/estatística & dados numéricos , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
11.
Strahlenther Onkol ; 191(8): 635-41, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25782685

RESUMO

PURPOSE: Concurrent chemoradiotherapy (CRT) is the standard treatment for advanced head and neck squamous cell carcinoma. In this phase II randomized study, the efficacy and toxicity of docetaxel, cisplatin and 5-fluorouracil induction chemotherapy (ICT) followed by concurrent CRT was compared with those after standard CRT alone in patients with locally advanced, unresectable head and neck cancer. PATIENTS AND METHODS: Between January 2007 and June 2009, 66 patients with advanced (stage III or IV) unresectable squamous cell carcinoma of the head and neck (oral cavity, oropharynx, hypopharynx, and larynx) were randomly assigned to two groups: one receiving two cycles of docetaxel, cisplatin, and 5-fluorouracil ICT followed by CRT with three cycles of cisplatin and one treated by CRT alone. Response rate, local tumor control (LTC), locoregional tumor control (LRTC), overall survival (OS), progression-free survival (PFS), and toxicity results were assessed. RESULTS: Three patients from the ICT + CRT group did not appear at the first treatment, so a total of 63 patients were evaluated in the study (30 ICT + CRT group and 33 CRT group). Three patients died of febrile neutropenia after ICT. The median follow-up time for surviving patients was 63 months (range 53-82 months). The rate of radiologic complete response was 63% following ICT + CRT, whereas 70% after CRT alone. There were no significant differences in the 3-year rates of LTC (56 vs. 57%), LRTC (42 vs. 50%), OS (43 vs. 55%), and PFS (41 vs. 50%) in the ICT + CRT group and in the CRT group, respectively. The rate of grade 3-4 neutropenia was significantly higher in the ICT + CRT group than in the CRT group (37 and 12%; p = 0.024). Late toxicity (grade 2 or 3 xerostomia) developed in 59 and 42% in the ICT + CRT and CRT groups, respectively. CONCLUSION: The addition of ICT to CRT did not show any advantage in our phase II trial, while the incidence of adverse events increased. The three deaths as a consequence of ICT call attention to the importance of adequate patient selection if ICT is considered.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Terapia Neoadjuvante , Neoplasias Otorrinolaringológicas/patologia , Neoplasias Otorrinolaringológicas/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Quimiorradioterapia/efeitos adversos , Cisplatino/administração & dosagem , Terapia Combinada/efeitos adversos , Intervalo Livre de Doença , Docetaxel , Feminino , Fluoruracila/administração & dosagem , Humanos , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Estadiamento de Neoplasias , Neoplasias Otorrinolaringológicas/mortalidade , Taxoides/administração & dosagem
12.
Magy Onkol ; 59(2): 95-101, 2015 Jun.
Artigo em Húngaro | MEDLINE | ID: mdl-26035156

RESUMO

The aim of the study was to compare different treatment plans - intensity-modulated and conformal - for head and neck cancer patients. Treatment plans were developed for ten head and neck cancer patients by applying four different techniques: two conventional 3D conformal plans (forward treatment planning, with two opposing fields 90o-270o and one asymmetric anterior field, matching in isocenter /Conv/, conformal parotis sparing plans /ConPas/), 3D conformal plans with inverse treatment planning techniques /INVCRT/ and intensity-modulated radiation therapy plans /IMRT/. The plans were made for the same target volumes PTV50 (elective) and PTV66 (boost-16 Gy). The cumulative dose was 66 Gy, and the Philips Pinnacle3 v8.0m TPS was used for treatment planning. The organs at risk (OAR) were as follows: spinal cord, brain stem, left and right parotis and oral cavity. The dose constrains and conditions for optimization were determined for IMRT techniques with 7 fields. During the optimization we applied two different protocols: in one case the plans were made by 40 segments for "step and shoot" IMRT techniques and by 14 segments for INVCRT, which were converted into static fields. The homogeneity (HI) and conformity (COIN) indices were calculated for planning target volumes and the comparisons were assessed on several dosimetric parameters for OARs. The IMRT, INVCRT, Conv and ConPas techniques for PTV50 planning target volume gave the following values for homogeneity index: 0.13, 0.18, 0.22, 0.19, and for conformity index: 0.76, 0.68, 0.13, 0.09. The spinal cord received a maximum of 38 Gy, 42 Gy, 45 Gy and 44 Gy for the PTV66. Mean doses of the oral cavity outside the target volume were 33 Gy, 36 Gy, 30 Gy and 48 Gy. When the 16 Gy boost treatment was applied on one side only, the mean dose for the parotis on the contralateral side was 28 Gy, 31 Gy, 49 Gy and 43 Gy, while 39 Gy, 41 Gy, 59 Gy and 53 Gy on the same side. The objectives of adequate target coverage and sparing of critical structures were fulfilled only with IMRT technique. Although the sparing of the oral cavity was the most effectively provided by the traditional technique - due to the arrangement of the fields - it gave the worst results regarding the parotis and the target volume. The highest dose for the oral cavity was given by the ConPas technique, which can cause serious early and late side effects. By increasing the number of segments for IMRT at a reasonable level, the dose for OARs can be reduced.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia (Especialidade)/métodos , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional , Institutos de Câncer/tendências , Humanos , Hungria , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada
13.
Magy Onkol ; 68(2): 155-162, 2024 Jul 16.
Artigo em Húngaro | MEDLINE | ID: mdl-39013089

RESUMO

In the Radiotherapy Centre of the National Institute of Oncology, Budapest, a 0.55 T MR scanner (MAGNETOM Free. Max) and a ring-like X-ray machine (ImagingRing) have been in operation since 2022. The MR scanner has a tunnel diameter of 80 cm, the X-ray machine has a ring diameter of 121 cm. The latter can also be used for cone-beam CT (CBCT) imaging. The MR scanner is mainly used for planning gynaecological brachytherapy (BT) treatments. Image distortions in MR imaging were investigated with a special grid phantom. After head and neck and breast implant, image quality of ImagingRing CBCT and planning CT was compared. The position of the radiation source was verified by radiographs taken during treatment. Despite the lower field strength, the image quality of the MR scanner was found to be adequate for treatment planning of gynaecological BT. Image distortions were found to be clinically negligible. On CBCT images obtained with ImagingRing, catheters could always be well identified, and anatomical organs were adequately visualized for head and neck treatments, but not for breast implants. The MR scanner is suitable for treatment planning for gynaecological BT due to its good image quality and low image distortion. The image quality of the ImagingRing is suitable for treatment planning for small body sizes, but not for larger sizes. The device can be used to in vivo check of the radiation source position during treatment.


Assuntos
Braquiterapia , Tomografia Computadorizada de Feixe Cônico , Imageamento por Ressonância Magnética , Planejamento da Radioterapia Assistida por Computador , Humanos , Braquiterapia/métodos , Braquiterapia/instrumentação , Feminino , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias dos Genitais Femininos/radioterapia , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Imagens de Fantasmas , Neoplasias da Mama/radioterapia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Hungria , Radioterapia Guiada por Imagem/métodos , Dosagem Radioterapêutica , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Implantes de Mama
14.
Radiat Oncol ; 19(1): 109, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143640

RESUMO

BACKGROUND AND PURPOSE: Cone beam computed tomography (CBCT) is routinely used in radiotherapy to localize target volume. The aim of our study was to determine the biological effects of CBCT dose compared to subsequent therapeutic dose by using in vitro chromosome dosimetry. MATERIALS AND METHODS: Peripheral blood samples from five healthy volunteers were irradiated in two phantoms (water filled in-house made cylindrical, and Pure Image CTDI phantoms) with 6 MV FFF X-ray photons, the dose rate was 800 MU/min and the absorbed doses ranged from 0.5 to 8 Gy. Irradiation was performed with a 6 MV linear accelerator (LINAC) to generate a dose-response calibration curve. In the first part of the investigation, 1-5 CBCT imaging was used, in the second, only 2 Gy doses were delivered with a LINAC, and then, in the third part, a combination of CBCT and 2 Gy irradiation was performed mimicking online adapted radiotherapy treatment. Metaphases were prepared from lymphocyte cultures, using standard cytogenetic techniques, and chromosomal aberrations were evaluated. Estimate doses were calculated from chromosome aberrations using dose-response curves. RESULTS: Samples exposed to X-ray from CBCT imaging prior to treatment exhibited higher chromosomal aberrations and Estimate dose than the 2 Gy therapeutic (real) dose, and the magnitude of the increase depended on the number of CBCTs: 1-5 CBCT corresponded to 0.04-0.92 Gy, 1 CBCT + 2 Gy to 2.32 Gy, and 5 CBCTs + 2 Gy to 3.5 Gy. CONCLUSION: The estimated dose based on chromosomal aberrations is 24.8% higher than the physical dose, for the combination of 3 CBCTs and the therapeutic 2 Gy dose, which should be taken into account when calculating the total therapeutic dose that could increase the risk of a second cancer. The clinical implications of the combined radiation effect may require further investigation.


Assuntos
Aberrações Cromossômicas , Tomografia Computadorizada de Feixe Cônico , Linfócitos , Imagens de Fantasmas , Dosagem Radioterapêutica , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Aberrações Cromossômicas/efeitos da radiação , Linfócitos/efeitos da radiação , Raios X , Relação Dose-Resposta à Radiação , Radiometria/métodos
15.
Head Neck ; 46(6): 1253-1262, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38600434

RESUMO

BACKGROUND: An international multidisciplinary panel of experts aimed to provide consensus guidelines describing the optimal intratumoral and intranodal injection of NBTXR3 hafnium oxide nanoparticles in head and neck squamous cell carcinoma (HNSCC) of the oral cavity, oropharynx, and cervical lymph nodes and to review data concerning safety, feasibility, and procedural aspects of administration. METHODS: The Delphi method was used to determine consensus. A 4-member steering committee and a 10-member monitoring committee wrote and revised the guidelines, divided into eight sections. An independent 3-member reading committee reviewed the recommendations. RESULTS: After two rounds of voting, strong consensus was obtained on all recommendations. Intratumoral and intranodal injection was deemed feasible. NBTXR3 volume calculation, choice of patients, preparation and injection procedure, potential side effects, post injection, and post treatment follow-up were described in detail. CONCLUSIONS: Best practices for the injection of NBTXR3 were defined, thus enabling international standardization of intratumoral nanoparticle injection.


Assuntos
Neoplasias de Cabeça e Pescoço , Injeções Intralesionais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Técnica Delphi , Háfnio/administração & dosagem , Óxidos/administração & dosagem , Nanopartículas/administração & dosagem , Masculino , Consenso , Feminino , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/patologia , Guias de Prática Clínica como Assunto
16.
Magy Onkol ; 68(2): 163-168, 2024 Jul 16.
Artigo em Húngaro | MEDLINE | ID: mdl-39013090

RESUMO

We present evaluation of junction of coplanar external beam photon fields and its portal dosimetric analysis for breast cancer with positive lymph nodes. In our work, we compared twelve patients affected by breast cancer with axillary and supraclavicular lymph nodes, using conformal external beam plans from a dosimetric point of view. 3-3 plans were prepared per patient. Three methods were used for the conformal technique to investigate the potential of lymph nodes treatment field's collimations. During the evaluation of the portal dosimetry images, it was concluded that the junction plane at isocenter appeared as a discrete coldline, when fitted the regional field with or without collimation manually and by the software. However, the coverage of the isocenter plane is strongly influenced by the linear accelerator and the fitted field edges. Based on our results, in order to avoid uncertainties arising from field junctions and the overdosed areas of the target volume, it is more appropriate to choose another advanced irradiation technique such as intensity-modulated radiation therapy.


Assuntos
Axila , Neoplasias da Mama , Linfonodos , Metástase Linfática , Fótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/patologia , Linfonodos/efeitos da radiação , Linfonodos/patologia , Fótons/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/métodos , Metástase Linfática/radioterapia , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos
17.
Magy Onkol ; 57(4): 264-8, 2013 Dec.
Artigo em Húngaro | MEDLINE | ID: mdl-24353992

RESUMO

Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in adults. The current standard therapy includes surgical resection or biopsy, followed by a combination of radiation and chemotherapy with temozolomide. After progression or recurrence there is only one recommended effective therapy, bevacizumab. Bevacizumab is a monoclonal VEGF inhibitor antibody, inhibiting the angiogenesis in highly vascularized tumors. Resent studies focused on adjuvant treatment with targeted therapy in newly diagnosed tumors. Our purpose is to evaluate the data from patients treated in our department investigate the clinical response and side effects profile and to compare these data with the international results. The applied protocol was well tolerated and side effects corresponded to the already reported ones. The median PFS and survival data correlate with those in the literature. The AVAglio study demonstrated that the addition of bevacizumab to the adjuvant therapy increased PFS significantly.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Glioblastoma/metabolismo , Glioblastoma/terapia , Terapia de Alvo Molecular/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Quimioterapia Adjuvante , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Radioterapia Adjuvante , Temozolomida , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
18.
J Contemp Brachytherapy ; 15(1): 48-56, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36970440

RESUMO

Purpose: To compare dosimetric parameters of brachytherapy (BT) treatment plans made with or without active source positions of the ring/ovoid (R/O) applicator in locally advanced cervical cancer patients. Material and methods: Sixty patients with cervical cancer without vaginal involvement were selected for the study, who received intra-cavitary/interstitial BT. For each patient, two plans with and without active source dwell positions in R/O were created, using the same dose-volume constraints. EQD2 total doses from external beam and BT of target volumes and organs at risk (OARs) between the competing plans were compared. Results: There was no significant difference in the dose of high-risk clinical target volume (HR-CTV) and gross tumor volume (GTV) between the plans with inactive vs. active R/O. The mean D98 of intermediate-risk clinical target volume (IR-CTV) was significantly lower with inactive R/O; however, the GEC-ESTRO (EMBRACE II study) and ABS criteria were fulfilled in 96% in both plans. There was no difference in dose homogeneity, but conformity of the plans with inactive R/O was higher. Doses to all OARs were significantly lower in plans without R/O activation. While all the plans without R/O activation fulfilled the recommended dose criteria for OARs, it was less achievable with R/O activation. Conclusions: Inactivation of R/O applicator results in similar dose coverage of the target volumes with lower doses to all OARs, as activation of R/O in cervix cancer patients when HR-CTV does not extend to R/O applicator. The use of active source positions in R/O shows worse performance regarding the fulfilment of the recommended criteria for OARs.

19.
Pathol Oncol Res ; 29: 1611123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168050

RESUMO

We aimed to characterize clinical and prognostical factors of primary head and neck squamous cell carcinoma (HNSCC) in 85 young patients (≤39 years, median age: 37 years; between 2000-2018) in comparison with 140 institutional general HNSCC patients (median age: 61.5 years). The patient's medical records were collected from the institutional database. The prevalence of smoking and alcohol consumption (65.8% and 48.1%) in the young group exceeded the regional population average but was below the institutional (86.4% and 55%) general HNSCC patient population. Primary tumor sites in the group of young patients were as follows: oral cavity (56.4%), oropharynx (17.6%), hypopharynx (11.7%), and larynx (14.1%). Cumulative five-year overall survival was 44.2% in the young group, but significantly better with early T (T1-2 vs. T3-4: 52.6% vs. 26.7%; p = 0.0058) and N0 status (N0 vs. N+: 65.2% vs. 32.3%; p = 0.0013). Young age, abstinence, earlier stage and laryngeal tumor site might predict a better prognosis. The age distribution and the high prevalence of traditional risk factors among the young patients as well as the predominance of oral cavity tumor localization suggest that the early onset of tumor development could be originated from the premature failure of the intrinsic protective mechanisms.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/complicações , Estudos Retrospectivos , Carcinoma de Células Escamosas/patologia
20.
Radiol Oncol ; 57(4): 516-523, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038418

RESUMO

BACKGROUND: The aim of the study was to dosimetrically compare interstitial high-dose-rate (HDR) brachytherapy (BT) and modern external beam radiotherapy modalities, as volumetric modulated arc therapy (VMAT) and stereotactic radiotherapy with Cyberknife (CK) of tumours of the tongue and floor of the mouth in terms of dose to the critical organs. PATIENTS AND METHODS: In National Institute of Oncology, Budapest, between March 2013 and August 2022 twenty patients (11 male/9 female) with stage T1-3N0M0 tongue (n = 14) and floor of mouth (n = 6) tumours received postoperative radiotherapy because of close/positive surgical margin and/or lymphovascular and/or perineural invasion. High-dose-rate interstitial brachytherapy applying flexible plastic catheters with a total dose of 15 × 3 Gy was used for treatment. In addition to BT plans VMAT and stereotactic CK plans were also made in all cases, using the same fractionation scheme and dose prescription. As for the organs at risk, the doses to the mandible, the ipsilateral and the contralateral salivary glands were compared. RESULTS: The mean volume of the planning target volume (PTV) was 12.5 cm3, 26.5 cm3 and 17.5 cm3 in BT, VMAT and CK techniques, respectively, due to different safety margin protocols. The dose to the mandible was the most favourable with BT, as for the salivary glands (parotid and submandibular) the CK technique resulted in the lowest dose. The highest dose to the critical organs was observed with the VMAT technique. The mean values of D2cm3 and D0.1cm3 for the critical organs were as follows for BT, VMAT and CK plans: 47.4% and 73.9%, 92.2% and 101.8%, 68.4% and 92.3% for the mandible, 4.8% and 6.7%, 7.3% and 13.8%, 2.3% and 5.1% for the ipsilateral parotid gland, 3.5% and 4.9%, 6.8% and 10.9%, 1.5% and 3.3% for the contralateral parotid gland, 7.3% and 9.4%, 9.0% and 14.3%, 3.6% and 5.6% for the contralateral submandibular gland. CONCLUSIONS: The present results confirm that BT, despite being an invasive technique, is dosimetrically clearly beneficial in the treatment of oral cavity tumours and is a modality worth considering when applying radiotherapy, not only as definitive treatment, but also postoperatively. The use of the CK in the head and neck region requires further investigation.


Assuntos
Braquiterapia , Neoplasias Bucais , Humanos , Masculino , Feminino , Braquiterapia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Órgãos em Risco , Neoplasias Bucais/radioterapia , Neoplasias Bucais/cirurgia , Língua
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