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1.
Anticancer Res ; 41(9): 4407-4410, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34475061

RESUMO

BACKGROUND/AIM: Many patients with gynecological malignancies receive postoperative radiotherapy, which can lead to fear and sleep disorders. We aimed to identify the prevalence of and risk factors for sleep disorders. PATIENTS AND METHODS: Sixty-two patients assigned to radiotherapy for gynecological malignancies were retrospectively evaluated. Seventeen characteristics were analyzed for associations with pre-radiotherapy sleep disorders including age, Karnofsky performance score, Charlson comorbidity index, history of additional malignancy, family history of gynecological cancer, distress score, emotional, physical or practical problems, tumor site/stage; chemotherapy, treatment volume, brachytherapy, and the COVID-19 pandemic. RESULTS: The prevalence of pre-radiotherapy sleep disorders was 46.8%. Sleep disorders were significantly associated with Charlson comorbidity index ≥3 (p=0.012), greater number of physical problems (p<0.0001), and advanced primary tumor stage (p=0.005). A trend was found for greater number of emotional problems (p=0.075). CONCLUSION: Pre-radiotherapy sleep disorders are common in patients with gynecological malignancies, particularly in those with specific risk factors. Patients should be offered early psychological support.


Assuntos
Neoplasias dos Genitais Femininos/radioterapia , Neoplasias dos Genitais Femininos/cirurgia , Radioterapia Adjuvante/métodos , Transtornos do Sono-Vigília/epidemiologia , Adulto , Braquiterapia , COVID-19/epidemiologia , Feminino , Neoplasias dos Genitais Femininos/patologia , Neoplasias dos Genitais Femininos/psicologia , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prevalência , Estudos Retrospectivos , Fatores de Risco , Transtornos do Sono-Vigília/etiologia , Resultado do Tratamento
2.
J Appl Clin Med Phys ; 22(9): 4-19, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34342124

RESUMO

A therapeutic medical physicist is responsible for reviewing radiation therapy treatment plans and patient charts, including initial treatment plans and new chart review, on treatment chart (weekly) review, and end of treatment chart review for both external beam radiation and brachytherapy. Task group report TG 275 examined this topic using a risk-based approach to provide a thorough analysis and guidance for best practice. Considering differences in resources and workflows of various clinical practice settings, the Professional Council of the American Association of Physicists in Medicine assembled this task group to develop a practice guideline on the same topic to provide a minimum standard that balances an appropriate level of safety and resource utilization. This medical physics practice guidelines (MPPG) thus provides a concise set of recommendations for medical physicists and other clinical staff regarding the review of treatment plans and patient charts while providing specific recommendations about who to be involved, and when/what to check in the chart review process. The recommendations, particularly those related to the initial plan review process, are critical for preventing errors and ensuring smooth clinical workflow. We believe that an effective review process for high-risk items should include multiple layers with collective efforts across the department. Therefore, in this report, we make specific recommendations for various roles beyond medical physicists. The recommendations of this MPPG have been reviewed and endorsed by the American Society of Radiologic Technologists and the American Association of Medical Dosimetrists.


Assuntos
Braquiterapia , Humanos , Física , Planejamento da Radioterapia Assistida por Computador , Relatório de Pesquisa , Sociedades , Estados Unidos
3.
J Int Med Res ; 49(8): 3000605211037477, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34423665

RESUMO

OBJECTIVE: This study aimed to quantify the effect of the dwell time deviation constraint (DTDC) on brachytherapy treatment for cervical cancer. METHODS: A retrospective study was carried out on 20 patients with radical cervical cancer. The DTDC values changed from 0.0 to 1.0 by a step size of 0.2. We adjusted the optimization objectives to ensure that all plans were optimized to a high-risk clinical target volume (HRCTV) D90 (the dose to 90% of the HRCTV) = 6 Gy, while keeping the dose to the organs at risk as low as possible. The dose-volume histogram parameters and the dwell time data were compared between plans with different DTDC values. RESULTS: The HRCTV volume covered by 150% of the prescription dose gradually increased with increasing DTDC values. As the DTDC value increased from 0.0 to 1.0, the effective dwell point proportion increased from 61.78% to 90.30%. The mean dwell time initially decreased with an increase in the DTDC value, reached the minimum value at DTDC = 0.8, then slightly increased at DTDC = 1.0. CONCLUSIONS: When using inverse planning simulated annealing optimization for radical cervical cancer cases, the recommended DTDC value is approximately 0.6 if the organ dose needs to be limited.


Assuntos
Braquiterapia , Neoplasias do Colo do Útero , Feminino , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Neoplasias do Colo do Útero/radioterapia
4.
Medicine (Baltimore) ; 100(31): e26844, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34397857

RESUMO

RATIONALE: Primary signet ring cell carcinoma of the uterine cervix is extremely rare and the clinical characteristics and prognosis are not well known and there are no specific guidelines for treatment. PATIENT CONCERNS: A 43-year-old woman was referred to our hospital for abnormal uterine bleeding lasting 1 month. DIAGNOSES: Histological examination revealed a signet ring cell carcinoma of the uterine cervix. After evaluation of extragenital origin, the patient was diagnosed International Federation of Gynecology and Obstetrics stage IIIC1 primary signet ring cell carcinoma or the uterine cervix. INTERVENTION: The patient was prescribed concomitant chemo-radiation followed by intracavitary brachytherapy. OUTCOMES: She showed no evidence of disease after treatment but, it recurred after 7 months of last treatment. LESSONS: Different approaches to diagnosis and treatment of this rare disease are needed and molecular pathological studies related to the onset of the disease are required.


Assuntos
Carcinoma de Células em Anel de Sinete , Colo do Útero , Quimiorradioterapia/métodos , Cisplatino/administração & dosagem , Neoplasias do Colo do Útero , Esfregaço Vaginal/métodos , Adulto , Antineoplásicos/administração & dosagem , Biópsia/métodos , Braquiterapia/métodos , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/fisiopatologia , Carcinoma de Células em Anel de Sinete/terapia , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Evolução Fatal , Feminino , Humanos , Recidiva Local de Neoplasia/patologia , Papillomaviridae/isolamento & purificação , Retratamento/métodos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/fisiopatologia , Neoplasias do Colo do Útero/terapia , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/etiologia
5.
Klin Monbl Augenheilkd ; 238(7): 781-787, 2021 Jul.
Artigo em Inglês, Alemão, Alemão | MEDLINE | ID: mdl-34376008

RESUMO

AIM: To report our experience with 106ruthenium-brachytherapy of peripheral capillary haemangioblastomas in patients with von Hippel-Lindau disease. DESIGN: Retrospective case series. METHODS: A total of 53 haemangioblastomas, treated with 106ruthenium-brachytherapy, were included in our study. The applied radiation dose, visual outcome, angioma activity, need for vitreoretinal surgery and incidence of secondary complications such as macular oedema, secondary glaucoma, vitreous haemorrhage, and epiretinal gliosis were assessed. RESULTS: All treated eyes could be preserved. In 11 patients (20.8%), single brachytherapy did not achieve complete inactivation of the tumour. 31% developed macular oedema postoperatively. Tractional retinal detachment developed in 23.8%, and epiretinal gliosis was observed in 2.4% of patients. Vitreoretinal surgery was necessary in 50% of all treated eyes. At the end of the follow-up, 40.5% of all treated eyes achieved visual acuity (VA) of 0.6 or better, and one third reached a VA of less than 0.1. Mean irradiation dose to the tumour apex was 144 Gy. Higher apex doses correlated with better tumour control of irradiated haemanigoblastomas and lower complication rates. CONCLUSIONS: Brachytherapy of peripheral retinal capillary haemangioblastomas is an effective treatment modality. Higher irradiation doses seem to lead to more successful treatment.


Assuntos
Braquiterapia , Hemangioblastoma , Neoplasias da Retina , Doença de von Hippel-Lindau , Hemangioblastoma/radioterapia , Humanos , Neoplasias da Retina/radioterapia , Estudos Retrospectivos , Doença de von Hippel-Lindau/complicações
6.
Int J Med Robot ; 17(5): e2303, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34231317

RESUMO

BACKGROUND: Prostate cancer is a common disease in men and has a relatively high mortality rate. However, the interventional medical equipment used for prostate biopsy and brachytherapy has always been a social concern. METHODS: To understand interventional medical equipment for prostate cancer, the structure of manual, semi-automatic and automatic medical equipment were considered as the mainline, while the corresponding research on these structures were the auxiliary lines. The characteristics and corresponding research status have been discussed. RESULTS: Interventional medical equipment for prostate cancer with different degrees of automation and its characteristics were determined, and the imaging principles and characteristics of computed tomography, transrectal ultrasound and magnetic resonance imaging have been briefly described. CONCLUSION: Certain feasible research suggestions have been proposed for future development from the perspective of structure, accuracy and safety. These include flexible and compact robot structures, high-precision image recognition and guidance, accurate dose planning and monitoring, real-time imaging monitoring without delay, high-precision needle insertion strategy, master-slave control, virtual reality and remote control.


Assuntos
Braquiterapia , Imagem por Ressonância Magnética Intervencionista , Neoplasias da Próstata , Humanos , Imageamento por Ressonância Magnética , Masculino , Ultrassonografia , Ultrassonografia de Intervenção
7.
J Appl Clin Med Phys ; 22(9): 189-214, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34312999

RESUMO

This work presents a comprehensive commissioning and workflow development process of a real-time, ultrasound (US) image-guided treatment planning system (TPS), a stepper and a US unit. To adequately benchmark the system, commissioning tasks were separated into (1) US imaging, (2) stepper mechanical, and (3) treatment planning aspects. Quality assurance US imaging measurements were performed following the AAPM TG-128 and GEC-ESTRO recommendations and consisted of benchmarking the spatial resolution, accuracy, and low-contrast detectability. Mechanical tests were first used to benchmark the electronic encoders within the stepper and were later expanded to evaluate the needle free length calculation accuracy. Needle reconstruction accuracy was rigorously evaluated at the treatment planning level. The calibration length of each probe was redundantly checked between the calculated and measured needle free length, which was found to be within 1 mm for a variety of scenarios. Needle placement relative to a reference fiducial and coincidence of imaging coordinate origins were verified to within 1 mm in both sagittal and transverse imaging planes. The source strength was also calibrated within the interstitial needle and was found to be 1.14% lower than when measured in a plastic needle. Dose calculations in the TPS and secondary dose calculation software were benchmarked against manual TG-43 calculations. Calculations among the three calculation methods agreed within 1% for all calculated points. Source positioning and dummy coincidence was tested following the recommendations of the TG-40 report. Finally, the development of the clinical workflow, checklists, and planning objectives are discussed and included within this report. The commissioning of real-time, US-guided HDR prostate systems requires careful consideration among several facets including the image quality, dosimetric, and mechanical accuracy. The TPS relies on each of these components to develop and administer a treatment plan, and as such, should be carefully examined.


Assuntos
Braquiterapia , Humanos , Masculino , Próstata/diagnóstico por imagem , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Ultrassonografia , Ultrassonografia de Intervenção
8.
Andrologia ; 53(9): e14122, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34319588

RESUMO

Radical prostatectomy, radiotherapy and active surveillance are three widely used treatment options for patients with low-risk prostate cancer, but the relative effects are controversial. We searched PubMed, Embase and Web of Science until June 2020, focusing on the studies comparing the effect of radical prostatectomy, radiotherapy and active surveillance in patients with low-risk prostate cancer. Through the random-effects model, dichotomous data were extracted and summarised by odds ratio with a 95% confidence interval. Twenty-two studies containing 185,363 participants were pooled for the comprehensive comparison. The Bayesian mixed network estimate demonstrated the cancer-specific mortality of radical prostatectomy was significantly lower than active surveillance (OR, 0.46; 95% CI 0.34-0.64) and external beam radiation therapy (OR, 0.66; 95% CI 0.46-0.96), but not brachytherapy (OR, 0.63; 95% CI 0.41-1.03). The brachytherapy demonstrated the best treatment ranking probability results in terms of all-cause mortality, while no significant difference was observed when compared with other three treatment modalities. Brachytherapy and radical prostatectomy were associated with a similar risk of cancer-specific mortality, and both of them were significantly superior to active surveillance and external beam radiation therapy; nevertheless, there was no significant difference among the aforementioned treatment methods in all-cause mortality.


Assuntos
Braquiterapia , Neoplasias da Próstata , Teorema de Bayes , Humanos , Masculino , Metanálise em Rede , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia
9.
J Appl Clin Med Phys ; 22(9): 82-93, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34263515

RESUMO

169 Yb has been recently used as an HDR brachytherapy source for cancer treatment. In this paper, dosimetric parameters of a new design of 169 Yb HDR brachytherapy source were determined by Monte Carlo (MC) method and film dosimetry. In this new source, the radioactive core has been encapsulated twice for safety purposes. The calculations of dosimetric parameters carried out using MC simulation in water and air phantom. In order to exclude photon contamination's cutoff energy, δ was set at 10 keV. TG-43U1 data dosimetric, including Sk , Λ, g(r), F(r, θ) was computed using outputs from the simulation and their statistical uncertainties were calculated. Dose distribution around the new prototype source in PMMA phantom in the framework of AAPM TG-43 and TG-55 recommendations was measured by Radiochromic film (RCF) Gafchromic EBT3. Obtained air kerma strength, Sk , and the dose rate constant, Λ, from simulation has a value of 1.03U ± 0.03 and 1.21 cGyh-1 U-1  ± 0.03, respectively. The radial dose function was calculated at radial distances between 0.5 and 10 cm with a maximum value of 1.15 ± 0.03 at 5-6 cm distances. The anisotropy functions for radial distances of 0.5-7 cm and angle distances 0° to180° were calculated. The dosimetric data of the new HDR 169 Yb source were compared with another reference source of 169 Yb-HDR and were found that has acceptable compatibility. In addition, the anisotropy function of the MC simulation and film dosimetry method at a distance of 1 cm from this source was obtained and a good agreement was found between the anisotropy results.


Assuntos
Braquiterapia , Anisotropia , Dosimetria Fotográfica , Humanos , Método de Monte Carlo , Radiometria , Dosagem Radioterapêutica
10.
J Appl Clin Med Phys ; 22(8): 72-82, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34231949

RESUMO

PURPOSE: Eye plaques are widely used for ocular melanoma and provide an effective alternative to enucleation with adequate tumor control. A COMS plaque utilizes a Silastic insert for precise positioning of the radioactive seeds with respect to the scleral surface of the eye; however, due to manufacturing variability, the insert may unintentionally increase or decrease the distance between the sources and tumor. The purpose of this work is to provide guidance in measuring and identifying outliers in Silastic inserts. The importance of regular quality assurance (QA) is illustrated in an experience where a systematic problem was detected and the manufacturer's 22-mm mold was corrected. METHODS: A detailed description of the molds and manufacturing process used to produce Silastic inserts is provided, including photographs of the process steps. The variability in Silastic insert production was evaluated by measuring the thickness of 124 Silastic inserts. An estimate of how the observed Silastic thickness discrepancies impact the dose to the tumor and critical eye structures was performed using homogeneous dose calculations. A standard QA protocol was developed to guide the clinical user. RESULTS: Thickness of the measured Silastic inserts ranged from 1.22 to 2.67 mm, demonstrating variation from the 2.25 mm standard. Six of the 22-mm inserts were outliers (Δthickness >3 standard deviations) and were excluded from the statistics. The outliers were investigated with the help of the manufacturer, who discovered that a systematic error was accidentally introduced into the 22-mm mold. CONCLUSIONS: Due to manufacturing errors or variability, the Silastic inserts used in COMS eye plaques may be thicker or thinner than the design standard. Such variations may impact tumor control or increase the risk of normal tissue side effects. A standardized QA program is recommended to detect variations and communicate unusual findings to the manufacturer.


Assuntos
Braquiterapia , Neoplasias Oculares , Dimetilpolisiloxanos , Neoplasias Oculares/radioterapia , Humanos , Radioisótopos do Iodo , Método de Monte Carlo , Dosagem Radioterapêutica
11.
J Appl Clin Med Phys ; 22(8): 284-294, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34318581

RESUMO

PURPOSE: High-dose-rate (HDR) prostate brachytherapy is an established technique for whole-gland treatment. For transrectal ultrasound (TRUS)-guided HDR prostate brachytherapy, image fusion with a magnetic resonance image (MRI) can be performed to make use of its soft-tissue contrast. The MIM treatment planning system has recently introduced image registration specifically for HDR prostate brachytherapy and has incorporated a Predictive Fusion workflow, which allows clinicians to attempt to compensate for differences in patient positioning between imaging modalities. In this study, we investigate the accuracy of the MIM algorithms for MRI-TRUS fusion, including the Predictive Fusion workflow. MATERIALS AND METHODS: A radiation oncologist contoured the prostate gland on both TRUS and MRI. Four registration methodologies to fuse the MRI and the TRUS images were considered: rigid registration (RR), contour-based (CB) deformable registration, Predictive Fusion followed by RR (pfRR), and Predictive Fusion followed by CB deformable registration (pfCB). Registrations were compared using the mean distance to agreement and the Dice similarity coefficient for the prostate as contoured on TRUS and the registered MRI prostate contour. RESULTS: Twenty patients treated with HDR prostate brachytherapy at our center were included in this retrospective evaluation. For the cohort, mean distance to agreement was 2.1 ± 0.8 mm, 0.60 ± 0.08 mm, 2.0 ± 0.5 mm, and 0.59 ± 0.06 mm for RR, CB, pfRR, and pfCB, respectively. Dice similarity coefficients were 0.80 ± 0.05, 0.93 ± 0.02, 0.81 ± 0.03, and 0.93 ± 0.01 for RR, CB, pfRR, and pfCB, respectively. The inclusion of the Predictive Fusion workflow did not significantly improve the quality of the registration. CONCLUSIONS: The CB deformable registration algorithm in the MIM treatment planning system yielded the best geometric registration indices. MIM offers a commercial platform allowing for easier access and integration into clinical departments with the potential to play an integral role in future focal therapy applications for prostate cancer.


Assuntos
Braquiterapia , Neoplasias da Próstata , Humanos , Imageamento por Ressonância Magnética , Masculino , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Estudos Retrospectivos , Ultrassonografia
12.
Br J Radiol ; 94(1125): 20210197, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34233471

RESUMO

OBJECTIVES: The main standard of care for locally advanced cervix carcinoma (LACC) is radiochemotherapy (RCT) followed by brachytherapy. A surgical approach may still be discussed based on pelvic MRI-derived residual tumour evaluation. As no interobserver agreement study has ever been conducted to our knowledge, the aim of the present study was to report on pelvic MRI accuracy and interobserver agreement in LACC. METHODS: We carried out a retrospective study in a French university hospital. Medical records of all consecutive patients treated with curative intent for LACC by RCT followed by brachytherapy and completion pelvic surgery between January 2014 and January 2020 were reviewed. Local response was assessed through pelvis MRI and histological analysis after completion surgery. MRI data were independently evaluated by two radiologists with varying experience. The two main interobserving criteria we used were complete response and residual tumour. RESULTS: 23 patients fulfilled the inclusion criteria. Agreement between the junior and senior radiologist was moderate to strong. Indeed, regarding main criteria, κ was 0.65 for complete response and 0.57 for residual tumour. Interestingly, the present study shows a lower sensitivity whatever the radiologists than in the international literature. CONCLUSION: The present study highlights a low interobserver variability regarding pelvic MRI in the assessment of RCT followed by brachytherapy in LACC. Yet, sensitivity was lower than in literature. ADVANCES IN KNOWLEDGE: Radiology is part of treatment decision-making, the issue of heterogeneity regarding radiologists' training and experience to cancer (sensitivity and specificity) turns essential, so does MRI accuracy.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Braquiterapia/métodos , Colo do Útero/diagnóstico por imagem , Quimiorradioterapia/métodos , Feminino , França , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
13.
Med Phys ; 48(8): 4542-4559, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34250607

RESUMO

PURPOSE: There is a growing trend towards the adoption of model-based calculation algorithms (MBDCAs) for brachytherapy dose calculations which can properly handle media and source/applicator heterogeneities. However, most of dose calculations in ocular plaque therapy are based on homogeneous water media and standard in-silico ocular phantoms, ignoring non-water equivalency of the anatomic tissues and heterogeneities in applicators and patient anatomy. In this work, we introduce EyeMC, a Monte Carlo (MC) model-based calculation algorithm for ophthalmic plaque brachytherapy using realistic and adaptable patient-specific eye geometries and materials. METHODS: We used the MC code PENELOPE in EyeMC to model Bebig IsoSeed I25.S16 seeds in COMS plaques and 106 Ru/106 Rh applicators that are coupled onto a customizable eye model with realistic geometry and composition. To significantly reduce calculation times, we integrated EyeMC with CloudMC, a cloud computing platform for radiation therapy calculations. EyeMC is equipped with an evaluation module that allows the generation of isodose distributions, dose-volume histograms, and comparisons with Plaque Simulator three-dimensional dose distribution. We selected a sample of patients treated with 125 I and 106 Ru isotopes in our institution, covering a variety of different type of plaques, tumor sizes, and locations. Results from EyeMC were compared to the original plan calculated by the TPS Plaque Simulation, studying the influence of heterogeneous media composition as well. RESULTS: EyeMC calculations for Ru plaques agreed well with manufacturer's reference data and data of MC simulations from Hermida et al. (2013). Significant deviations, up to 20%, were only found in lateral profiles for notched plaques. As expected, media composition significantly affected estimated doses to different eye structures, especially in the 125 I cases evaluated. Dose to sclera and lens were found to be about 12% lower when considering real media, while average dose to tumor was 9% higher. 106 Ru cases presented a 1%-3% dose reduction in all structures using real media for calculation, except for the lens, which showed an average dose 7.6% lower than water-based calculations. Comparisons with Plaque Simulator calculations showed large differences in dose to critical structures for 106 Ru notched plaques. 125 I cases presented significant and systematic dose deviations when using the default calculation parameters from Plaque Simulator version 5.3.8., which were corrected when using calculation parameters from a custom physics model for carrier-attenuation and air-interface correction functions. CONCLUSIONS: EyeMC is a MC calculation system for ophthalmic brachytherapy based on a realistic and customizable eye-tumor model which includes the main eye structures with their real composition. Integrating this tool into a cloud computing environment allows to perform high-precision MC calculations of ocular plaque treatments in short times. The observed variability in eye anatomy among the selected cases justifies the use of patient-specific models.


Assuntos
Braquiterapia , Neoplasias Oculares , Neoplasias Oculares/radioterapia , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
16.
Theranostics ; 11(15): 7589-7599, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34158868

RESUMO

Rational: Interstitial brachytherapy (BT) is a promising radiation therapy for cancer; however, the efficacy of BT is limited by tumor radioresistance. Recent advances in materials science and nanotechnology have offered many new opportunities for BT. Methods: In this work, we developed a biomimetic nanotheranostic platform for enhanced BT. Core-shell Au@AuPd nanospheres (CANS) were synthesized and then encapsulated in platelet (PLT)-derived plasma membranes. Results: The resulting PLT/CANS nanoparticles efficiently evaded immune clearance and specifically accumulated in tumor tissues due to the targeting capabilities of the PLT membrane coating. Under endoscopic guidance, a BT needle was manipulated to deliver appropriate radiation doses to orthotopic colon tumors while sparing surrounding organs. Accumulated PLT/CANS enhanced the irradiation dose deposition in tumor tissue while alleviating tumor hypoxia by catalyzing endogenous H2O2 to produce O2. After treatment with PLT/CANS and BT, 100% of mice survived for 30 days. Conclusions: Our work presents a safe, robust, and efficient strategy for enhancing BT outcomes when adapted to treatment of intracavitary and unresectable tumors.


Assuntos
Materiais Biomiméticos/farmacologia , Plaquetas , Braquiterapia , Ouro/farmacologia , Nanopartículas Metálicas/uso terapêutico , Neoplasias Experimentais/radioterapia , Paládio/farmacologia , Animais , Linhagem Celular Tumoral , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Células RAW 264.7
17.
Radiother Oncol ; 161: 40-46, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34089752

RESUMO

BACKGROUND: The ASCO/CCO guidelines recommend brachytherapy (BT) boost for eligible intermediate- (IR) or high-risk (HR) prostate cancer (PCa) patients. We present efficacy, toxicity and quality-of-life (QoL) outcomes in patients treated on a prospective protocol of MRI dose-painted high-dose-rate BT boost (HDR-BT) followed by 5-fraction pelvic radiotherapy (RT) and 6-18 months of androgen deprivation therapy (ADT). METHODS: In this phase I/II study, IR or HR PCa patients received HDR-BT 15 Gy × 1 to prostate and up to 22.5 Gy to MRI nodule, followed by 25 Gy in 5, weekly fractions to pelvis. Toxicity was assessed using CTCAEv3.0, and QoL was captured using EPIC questionnaire. Biochemical failure (BF; nadir + 2.0), and proportion of patients with PSA < 0.4 ng/ml at 4-years (4yPSARR) were evaluated. A minimally clinically important change (MCIC) was recorded if QoL score decreased >0.5 standard deviation of baseline scores. RESULTS: Thirty-one patients (NCCN 3.2% favorable IR, 48.4% unfavorable IR and 48.4% HR) completed treatment with a median follow-up of 61 months. Median D90 to MR nodule was 19.0 Gy and median prostate V100% was 96.5%. The actuarial 5-year BF rate was 18.2%, and the 4yPSARR was 71%. One patient died of PCa. Acute grade 2 and 3 toxicities: GU: 50%, 7%, and GI: 3%, none, respectively. Late grade 2 and 3 toxicities were: GU: 23%, 3%, and GI: 7%, none, respectively. Proportion of patients with MCIC was 7.7% for urinary domain and 32.0% for bowel domain. CONCLUSIONS: This novel treatment protocol incorporating MRI dose-painted HDR-BT boost and 5-fraction pelvic RT with ADT is well tolerated.


Assuntos
Braquiterapia , Neoplasias da Próstata , Antagonistas de Androgênios , Braquiterapia/efeitos adversos , Humanos , Masculino , Pelve , Estudos Prospectivos , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Dosagem Radioterapêutica
18.
Radiother Oncol ; 161: 74-82, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34089754

RESUMO

BACKGROUND AND PURPOSE: 1.5 Tesla magnetic resonance imaging radiotherapy linear accelerator (MR-Linac) is gaining interest for treatment of localized prostate cancer. Clinical evidence is lacking and it therefore remains uncertain whether MR-Linac is cost-effective. An early health economic analysis was performed to calculate the necessary relative reduction in complications and the maximum price of MR-Linac (5 fractions) to be cost-effective compared to 5, 20 and 39 fractionation schedules of external beam radiotherapy (EBRT) and low-dose-rate (LDR) brachytherapy. MATERIALS AND METHODS: A state transition model was developed for men with localized prostate cancer. Complication rates such as grade ≥2 urinary, grade ≥2 bowel and sexual complications, and utilities were based on systematic literature searches. Costs were estimated from a Dutch healthcare perspective. Threshold analyses were performed to identify the thresholds of complications and costs for MR-Linac to be cost-effective, while holding other outcomes such as biochemical progression and mortality constant. One-way sensitivity analyses were performed to outline uncertainty outcomes. RESULTS: At €6460 per patient, no reductions in complications were needed to consider MR-Linac cost-effective compared to EBRT 20 and 39 fractions. Compared to EBRT 5 fractions and LDR brachytherapy, MR-Linac was found to be cost-effective when complications are relatively reduced by 54% and 66% respectively. Results are highly sensitive to the utilities of urinary, bowel and sexual complications and the probability of biochemical progression. CONCLUSIONS: MR-Linac is found to be cost-effective compared to 20 and 39 fractions EBRT at baseline. For MR-Linac to become cost-effective over 5 fractions EBRT and LDR brachytherapy, it has to reduce complications substantially or be offered at lower costs.


Assuntos
Braquiterapia , Neoplasias da Próstata , Fracionamento da Dose de Radiação , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia
19.
Radiother Oncol ; 161: 241-250, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34171451

RESUMO

BACKGROUND: Prostate radiotherapy has been associated with an increased risk of developing a second malignancy (SM). However, relative SM probabilities following treatment with contemporary radiation techniques such as stereotactic body radiotherapy (SBRT) or moderately hypofractionated intensity modulated radiotherapy (HF-IMRT) remain unknown. METHODS: A cohort analysis was performed of men from a nationally representative database with localized prostate cancer with at least 60 months of follow-up comparing SM probability amongst men receiving either radical prostatectomy (RP), conventionally fractionated intensity-modulated radiotherapy (CF-IMRT), HF-IMRT, brachytherapy (BT), or SBRT, using multivariable logistic models, which were used to generate predicted probabilities. Additionally, propensity score-adjusted pairwise assessments of modalities were performed. RESULTS: For 303,432 patients included in the study, median follow-up was 9.08 years (IQR 7.01-11.21). Predicted rates of SM by treatment modality and adjusted odds ratios (AOR) for development of SM (referent: RP) were: 6.0% for RP (AOR n/a), 7.1% for CF-IMRT (AOR 1.20, 95%CI 1.14-1.25, P < 0.001), 7.3% for HF-IMRT (AOR 1.25, 95%CI 1.01-1.55, P = 0.045), 6.6% for BT (AOR 1.11, 95%CI 1.07-1.16, P < 0.001), and 5.7% for SBRT (AOR 0.95, 95%CI 0.81-1.12, P = 0.567). On propensity score-adjusted analysis, SBRT was associated with lower odds of SM compared to CF-IMRT (AOR 0.78, 95%CI 0.66-0.93, P = 0.005); no significant difference was found when SBRT was compared to RP (AOR 0.86, 95%CI 0.73-1.03, P = 0.102). CONCLUSIONS: Conventionally fractionated intensity-modulated radiotherapy, moderately hypofractionated intensity-modulated radiotherapy, and brachytherapy but not stereotactic body radiotherapy were associated with increased probability of a second malignancy compared to radical prostatectomy. Patients treated with SBRT may be at lower risk of second malignancy due to improved conformality, radiobiological differences or patient selection. The possibility that SBRT in select patients may minimize the probability of SM underscores the need for assessment of second malignancy risk in prospective studies of SBRT.


Assuntos
Braquiterapia , Segunda Neoplasia Primária , Neoplasias da Próstata , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Masculino , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/etiologia , Pontuação de Propensão , Estudos Prospectivos , Neoplasias da Próstata/radioterapia , Radiocirurgia/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos
20.
In Vivo ; 35(4): 2313-2319, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34182511

RESUMO

BACKGROUND/AIM: Non-melanoma skin cancers (NMSC) are the most common neoplasms worldwide and their incidence has been proven to increase in recent years and their treatment should aim at cancer cure as well as cosmetic and functional results. The aim of the study was to report the results of our mono-institutional series of high-dose-rate radiotherapy (cHDR-RT) in NMSC, based on a homogenous technique and two different treatment schedules. PATIENTS AND METHODS: All patients affected by NMSC who were consecutively evaluated and treated at our Interventional Oncology Center from October 2018 to August 2020, were included. Patients underwent cHDR-RT using flap applicators and remotely afterloaded Ir-192 sources. RESULTS: Overall, 51 patients were treated for a total of 67 lesions. Local control (LC) and disease-specific survival (DSS) were 94.0% and 100%, respectively. Grade 1, grade 2, grade 3 and grade 4 acute toxicity rates were 24.6%, 3.5%, 3.5%, and 0.0%, respectively. The cosmetic results were graded as excellent/good, fair, and poor in 73.7%, 19.3%, and 7.0%. CONCLUSION: cHDR-RT of NMSC is an effective alternative to surgery due to excellent outcomes both in terms of local control and aesthetic results especially in the face.


Assuntos
Braquiterapia , Neoplasias Cutâneas , Estética , Humanos , Dosagem Radioterapêutica , Neoplasias Cutâneas/radioterapia
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