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1.
Curr Oncol ; 29(9): 6564-6572, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36135085

RESUMO

PURPOSE: A single-institution prospective pilot study was conducted to the assess correlation between salivary amylase and xerostomia in patients with head and neck squamous cell carcinoma (HNSCC) treated with intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: Serum saliva amylase, clinician-reported xerostomia (using Common Terminology Criteria for Adverse Events), and patient-reported xerostomia (using 8-item self-reported xerostomia-specific questionnaire) were prospectively collected at baseline, during treatment and thereafter. Correlations between variables were assessed by correlation matrices. RESULTS: Twelve patients with locally advanced HNSCC formed the cohort. Eighty-three percent were male, 75% were smokers, 100% had clinical positive lymph nodes at diagnosis, and 42% received induction chemotherapy. All patients received IMRT with concurrent cisplatin-based chemotherapy. No grade ≥4 xerostomia was observed. Severe (G3) acute and late xerostomia occurred in five cases (41.7%) and two cases (16.7%), respectively. Patient-reported xerostomia scores were highly correlated with the clinician-reported scores (ρ = 0.73). A significant correlation was recorded between the concentration of amylase and the acute (ρ = -0.70) and late (ρ = -0.80) xerostomia. CONCLUSION: Preliminary results are encouraging. Prospective clinical trials are needed to define the value of salivary amylase in the management of HNSCC tumors.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Radioterapia de Intensidade Modulada , Xerostomia , Amilases/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Cisplatino/uso terapêutico , Feminino , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Glândula Parótida , Projetos Piloto , Estudos Prospectivos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Xerostomia/etiologia
2.
Cancer Radiother ; 26(6-7): 865-870, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36064531

RESUMO

The standard management of locally advanced rectal tumors as cT3-T4 and/or N0/N1 is based on preoperative treatment combining radiotherapy of 45 to 50Gy and chemotherapy based on 5-fluorouracil. Intensity-modulated radiotherapy has already shown its interest compared to conformal radiotherapy in other locations, like in pelvic cancer. The role of intensity-modulated radiotherapy in the pre/postoperative treatment of rectal cancers is not a standard of care. Published studies showed its feasibility with the objective of less toxicity with equivalent efficacy.


Assuntos
Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Neoplasias Retais , Fluoruracila/uso terapêutico , Humanos , Terapia Neoadjuvante , Neoplasias Retais/patologia
3.
Cancer Radiother ; 26(6-7): 890-893, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36075830

RESUMO

Despite significant therapeutic advances in the treatment of locally advanced inoperable non-small cell lung cancer (NSCLC), notably through adjuvant immunotherapy, the rate of therapeutic failure remains high. The use of positron emission tomography with fluorodeoxyglucose (FDG-PET), respiratory motion and intensity modulated radiotherapy (IMRT) have led to therapeutic improvements with reduced toxicity and better local control. The optimal dose to be delivered remains unknown due to discordant results of studies for almost 20 years and the way to define the area to benefit from a dose increase (whole volume, subvolume defined by pre- or per-radiotherapy PET).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
4.
Technol Cancer Res Treat ; 21: 15330338221114499, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112945

RESUMO

Purpose: To compare the sensitivity of ArcCHECK (AC), portal dosimetry (PD), and an in-house logfile-based system (LF) to multileaf collimators (MLC) aperture errors and the ability to identify these errors. Methods and Materials: For 12 retrospective original head and neck volumetric modulated arc therapy (VMAT) plans, MLC aperture errors of ± 0.4mm, ± 1.2mm, ± 2mm, and ± 3mm were introduced for each plan, resulting in 96 plans with errors. AC, PD, and LF were used for the gamma evaluation at 3%/3mm, 3%/2mm, and 2%/2mm criteria. Gradient analysis was used to evaluate the sensitivity to MLC aperture errors. The area under the curve (AUC) obtained from the receiver operating characteristic (ROC) curve was used to evaluate the ability to identify MLC aperture errors and dose errors, and the optimal cut-off value to identify the error was obtained. Results: The gamma pass rate (%GP) of LF had the smallest descent gradient as the MLC error increases in any case. The descent gradient of PD was larger than AC, except for the case at the 2%/2mm criteria. For the 3%/3mm criteria, the MLC aperture errors that can be perfectly identified by AC, PD, and LF were ± 3mm, ± 2mm, and ± 1.2mm, respectively, and the average percent dose error (%DEs) of dose metrics in targets that can be perfectly identified were 4% to 5%, 3% to 4%, and 2% to 3%, respectively. For the 3%/2mm criteria, the errors that AC, PD, and LF can perfectly identify were the same as the 3%/3mm criteria. For the 2%/2mm criteria, AC can perfectly identify the MLC error of ± 2mm and the %DE of 3% to 4%. PD and LF can identify the MLC error of ± 1.2mm and the %DE of 2% to 3%. Conclusion: Different patient-specific quality assurance (PSQA) systems have different sensitivity and recognition abilities to MLC aperture errors. Institutions should formulate their own customized %GP limits based on their PSQA process through ROC or other methods.


Assuntos
Radioterapia de Intensidade Modulada , Raios gama , Humanos , Radiometria , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
5.
Phys Med Biol ; 67(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36093921

RESUMO

Objective.To establish an open framework for developing plan optimization models for knowledge-based planning (KBP).Approach.Our framework includes radiotherapy treatment data (i.e. reference plans) for 100 patients with head-and-neck cancer who were treated with intensity-modulated radiotherapy. That data also includes high-quality dose predictions from 19 KBP models that were developed by different research groups using out-of-sample data during the OpenKBP Grand Challenge. The dose predictions were input to four fluence-based dose mimicking models to form 76 unique KBP pipelines that generated 7600 plans (76 pipelines × 100 patients). The predictions and KBP-generated plans were compared to the reference plans via: the dose score, which is the average mean absolute voxel-by-voxel difference in dose; the deviation in dose-volume histogram (DVH) points; and the frequency of clinical planning criteria satisfaction. We also performed a theoretical investigation to justify our dose mimicking models.Main results.The range in rank order correlation of the dose score between predictions and their KBP pipelines was 0.50-0.62, which indicates that the quality of the predictions was generally positively correlated with the quality of the plans. Additionally, compared to the input predictions, the KBP-generated plans performed significantly better (P< 0.05; one-sided Wilcoxon test) on 18 of 23 DVH points. Similarly, each optimization model generated plans that satisfied a higher percentage of criteria than the reference plans, which satisfied 3.5% more criteria than the set of all dose predictions. Lastly, our theoretical investigation demonstrated that the dose mimicking models generated plans that are also optimal for an inverse planning model.Significance.This was the largest international effort to date for evaluating the combination of KBP prediction and optimization models. We found that the best performing models significantly outperformed the reference dose and dose predictions. In the interest of reproducibility, our data and code is freely available.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Bases de Conhecimento , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Reprodutibilidade dos Testes
6.
JAMA Netw Open ; 5(9): e2230704, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36074462

RESUMO

Importance: National guidelines allow consideration of postoperative radiation therapy (PORT) among patients with incompletely resected non-small cell lung cancer (NSCLC). However, there is a paucity of prospective data because recently completed trials excluded patients with positive surgical margins. In addition, unlike for locally advanced NSCLC, the role of intensity-modulated radiation therapy (IMRT) for PORT remains unclear. Objective: To evaluate trends of IMRT use for PORT in the US and the association of IMRT with survival outcomes among patients with incompletely resected NSCLC. Design, Setting, and Participants: This retrospective cohort study used data from the National Cancer Database for patients diagnosed between January 2004 and December 2019 with incompletely resected NSCLC who underwent upfront surgery with positive surgical margins followed by PORT. Exposures: IMRT vs 3D conformal radiation therapy (3DCRT) for PORT. Main Outcomes and Measures: The main outcome was overall survival. Multivariable Cox proportional hazards regression assessed the association of IMRT vs 3DCRT with overall survival. Multivariable logistic regression identified variables associated with IMRT. Propensity score matching (1:1) was performed based on variables of interest. Results: A total of 4483 patients (2439 men [54.4%]; median age, 67 years [IQR, 60-73 years]) were included in the analysis. Of those, 2116 (47.2%) underwent 3DCRT and 2367 (52.8%) underwent IMRT. Median follow-up was 48.5 months (IQR, 31.1-77.2 months). The proportion of patients who underwent IMRT increased from 14.3% (13 of 91 patients) in 2004 to 70.7% (33 of 471 patients) in 2019 (P < .001). IMRT was associated with improved overall survival compared with 3DCRT (adjusted hazard ratio, 0.84; 95% CI, 0.78-0.91; P < .001). Similar findings were observed for 1463 propensity score-matched pairs; IMRT was associated with improved 5-year overall survival compared with 3DCRT (37.3% vs 32.2%; hazard ratio, 0.88; 95% CI, 0.80-0.96; P = .003). IMRT use was associated with receipt of treatment at an academic facility (adjusted odds ratio [aOR], 1.15; 95% CI, 1.00-1.33; P = .049), having T4 stage tumors (aOR, 1.50; 95% CI, 1.13-1.99; P = .005) or N2 or N3 stage tumors (aOR, 1.25; 95% CI, 1.04-1.51; P = .02), and receipt of pneumonectomy (aOR, 1.35; 95% CI, 1.02-1.80; P = .04). Conclusion and Relevance: This cohort study found that use of IMRT for PORT among patients with incompletely resected NSCLC increased in the US from 2004 to 2019 and was associated with improved survival compared with 3DCRT. Further studies are warranted to investigate the role of different radiation therapy techniques for PORT.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Idoso , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Estudos de Coortes , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Masculino , Margens de Excisão , Estadiamento de Neoplasias , Estudos Prospectivos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Resultado do Tratamento
7.
Medicine (Baltimore) ; 101(36): e29290, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36086767

RESUMO

Based on Pinnacle39.10 treatment planning system (TPS) automatic planning module, we investigated the effect of minimum segmentation area (MSA) parameters on Auto-Plan Intensity Modulated Radiotherapy (AP-IMRT) without affecting the dose distribution of the target and the Organ at Risk (OAR). The results provided the basis for the ideal MSA parameters in the design of AP-IMRT plan. Ten patients with cervical cancer in our hospital were selected randomly for AP-IMRT design. Each patient was devised with 10 AP-IMRT plans. The prescription dose of PTV was 50 Gy/25 fractions. The radiotherapy plans of all patients were adopted with 7 field-averaged fixed fields. The MSA was set to 4 cm2, 9 cm2, 14 cm2, 20 cm2, 25 cm2, 40 cm2, 50 cm2, 60 cm2, 80 cm2, and 100 cm2. Plan quality and delivery efficiency were evaluated based on dose-volume histograms (DVHs), control points, monitor units (MUs), dosimetric measurement verification results, and plan delivery time. Except for the small difference in monitor units, the number of segmentations and target dose coverage, there were no statistically significant differences between the other dosimetric parameters in the planning target volumes. With the increase of MSA, the total number of MUs in AP-IMRT decreased from (649 ± 32) MUs to (312 ± 26) MUs, and the total number of segmentations decreased from (69 ± 1) to (28 ± 3). There was no statistical significance in the dose distribution of AP-IMRT target area with the MSA of 4-50 cm2 (P > .05). There was no significant difference in OAR dose between AP-IMRT plans with different MSA (P > .05). The calculated gamma indices using the 3% /3 mm and 2%/2 mm criteria. Both of the gamma pass rate and DTA pass rate all ≥95% under the condition of MSA are greater than 4 cm2, and the difference was no statistically significant (P > .05). The plan delivery times decreased with increasing MSA (P < .05). When using Pinnacle3 9.10 TPS to design AP-IMRT plan for cervical cancer, the parameter of MSA can be increased appropriately. Increasing the MSA allows for improved plan delivery accuracy and efficiency without significantly affecting the AP-IMRT plan quality. The MSA in the range of 14 to 50 cm2 can obtain a more reasonable dose distribution in the target area while the dose of target area and OAR had no significant changes. It is important to improve the plan quality, delivery accuracy, and efficiency for cervical AP-IMRT radiation therapy.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero , Feminino , Humanos , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias do Colo do Útero/radioterapia
8.
Int J Mol Sci ; 23(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36076990

RESUMO

Neutrophils, also known as polymorphonuclear leukocytes (PMNs), form a significant component of the innate host response, and the consequence of the interaction between the oral microbiota and PMNs is a crucial determinant of oral health status. The impact of radiation therapy (RT) for head and neck tumour (HNT) treatment on the oral innate immune system, neutrophils in particular, and the oral microbiome has not been thoroughly investigated. Therefore, the objective of this study was to characterize RT-mediated changes in oral neutrophils (oPMNs) and the oral microbiome in patients undergoing RT to treat HNTs. Oral rinse samples were collected prior to, during and post-RT from HNT patients receiving RT at Dental Oncology at Princess Margaret Cancer Centre. The oPMNs counts and activation states were analysed using flow cytometry, and the oral microbiome was analysed using 16S rRNA gene sequencing. Statistically significant (p < 0.05) drops in oPMN counts and the activation states of the CD11b, CD16, CD18, CD64 and H3Cit markers from pre-RT to post-RT were observed. Moreover, exposure to RT caused a significant reduction in the relative abundance of commensal Gram-negative bacteria and increased the commensal Gram-positive microbes. Ionizing radiation for the treatment of HNTs simultaneously decreased the recruitment of oPMNs into the oral cavity and suppressed their activation state. The oral microbiome composition post-RT was altered significantly due to RT which may favour the colonization of specific microbial communities unfavourable for the long-term development of a balanced oral microbiome.


Assuntos
Neoplasias de Cabeça e Pescoço , Microbiota , Radioterapia de Intensidade Modulada , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Imunidade Inata , Estudos Prospectivos , RNA Ribossômico 16S/genética , Radioterapia
9.
Cancer Control ; 29: 10732748221126935, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36075003

RESUMO

OBJECTIVE: To assess the effect of pretreatment body mass index (BMI) and the extent of change in BMI (ΔBMI) during the treatment course on the treatment outcomes in patients with nasopharyngeal carcinoma (NPC) receiving volumetric modulated arc therapy (VMAT). METHODS: Data pertaining to 498 consecutive NPC patients with stage I-IVA disease who received VMAT between January 2010 and November 2011 at a single center were retrospectively analyzed. Univariate Kaplan-Meier and multivariate Cox regression analyses were used to evaluate the prognostic significance of pretreatment BMI and ΔBMI. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cut-off point of ΔBMI. RESULTS: The 5-year loco-regional failure-free (L-FFR), distant failure-free survival (D-FFR), disease-free survival (DFS), and overall survival (OS) rates were 90.6%, 83.7%, 71.5% and 79.3%, respectively. The 5-year L-FFR, D-FFR, DFS, OS rates for NPC patients with ΔBMI ≤1 kg/m2 vs ΔBMI >1 kg/m2 were 92.3% vs 89.3% (P = .137), 90.9% vs 78.5% (P < .001), 80.4% vs 65.1% (P < .001), and 88.0% vs 73.0% (P < .001), respectively. ΔBMI >1 kg/m2 was an independent predictor of D-FFR (P = .002), DFS (P = .002), and OS (P = .001). CONCLUSIONS: ΔBMI during treatment course may have a significant impact on the prognosis of NPC patients receiving VMAT.


Assuntos
Carcinoma , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Índice de Massa Corporal , Carcinoma/radioterapia , Intervalo Livre de Doença , Humanos , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Prognóstico , Estudos Retrospectivos
10.
Sci Rep ; 12(1): 15282, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36088382

RESUMO

We established a multi-institution model (big model) of knowledge-based treatment planning with over 500 treatment plans from five institutions in volumetric modulated arc therapy (VMAT) for prostate cancer. This study aimed to clarify the efficacy of using a large number of registered treatment plans for sharing the big model. The big model was created with 561 clinically approved VMAT plans for prostate cancer from five institutions (A: 150, B: 153, C: 49, D: 60, and E: 149) with different planning strategies. The dosimetric parameters of planning target volume (PTV), rectum, and bladder for two validation VMAT plans generated with the big model were compared with those from each institutional model (single-institution model). The goodness-of-fit of regression lines (R2 and χ2 values) and ratios of the outliers of Cook's distance (CD) > 4.0, modified Z-score (mZ) > 3.5, studentized residual (SR) > 3.0, and areal difference of estimate (dA) > 3.0 for regression scatter plots in the big model and single-institution model were also evaluated. The mean ± standard deviation (SD) of dosimetric parameters were as follows (big model vs. single-institution model): 79.0 ± 1.6 vs. 78.7 ± 0.5 (D50) and 0.13 ± 0.06 vs. 0.13 ± 0.07 (Homogeneity Index) for the PTV; 6.6 ± 4.0 vs. 8.4 ± 3.6 (V90) and 32.4 ± 3.8 vs. 46.6 ± 15.4 (V50) for the rectum; and 13.8 ± 1.8 vs. 13.3 ± 4.3 (V90) and 39.9 ± 2.0 vs. 38.4 ± 5.2 (V50) for the bladder. The R2 values in the big model were 0.251 and 0.755 for rectum and bladder, respectively, which were comparable to those from each institution model. The respective χ2 values in the big model were 1.009 and 1.002, which were closer to 1.0 than those from each institution model. The ratios of the outliers in the big model were also comparable to those from each institution model. The big model could generate a comparable VMAT plan quality compared with each single-institution model and therefore could possibly be shared with other institutions.


Assuntos
Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
11.
Radiat Oncol ; 17(1): 155, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096874

RESUMO

BACKGROUND: To compare the dosimetric profiles of volumetric modulated arc therapy (VMAT) plans using the fast-rotating O-ring linac (the Halcyon system) based on a dual-layer stacked multi-leaf collimator and helical tomotherapy (HT) for nasopharyngeal cancer (NPCa). METHODS: For 30 NPCa patients, three sets of RT plans were generated, under the same policy of contouring and dose constraints: HT plan; Halcyon VMAT plan with two arcs (HL2arc); and Halcyon VMAT plan with four arcs (HL4arc), respectively. The intended dose schedule was to deliver 67.2 Gy to the planning gross target volume (P-GTV) and 56.0 Gy to the planning clinical target volume (P-CTV) in 28 fractions using the simultaneously integrated boost concept. Target volumes and organ at risks dose metrics were evaluated for all plans. Normal tissue complication probabilities (NTCP) for esophagus, parotid glands, spinal cord, and brain stem were compared. RESULTS: The HT plan achieved the best dose homogeneity index for both P_GTV and P_CTV, followed by the HL4arc and L2arc plans. No significant difference in the dose conformity index (CI) for P_GTV was observed between the HT plan (0.80) and either the HL2arc plan (0.79) or the HL4arc plan (0.83). The HL4arc plan showed the best CI for P_CTV (0.88), followed by the HL2arc plan (0.83) and the HT plan (0.80). The HL4arc plan (median, interquartile rage (Q1, Q3): 25.36 (22.22, 26.89) Gy) showed the lowest Dmean in the parotid glands, followed by the HT (25.88 (23.87, 27.87) Gy) and HL2arc plans (28.00 (23.24, 33.99) Gy). In the oral cavity (OC) dose comparison, the HT (22.03 (19.79, 24.85) Gy) plan showed the lowest Dmean compared to the HL2arc (23.96 (20.84, 28.02) Gy) and HL4arc (24.14 (20.17, 27.53) Gy) plans. Intermediate and low dose regions (40-65% of the prescribed dose) were well fit to the target volume in HL4arc, compared to the HT and HL2arc plans. All plans met the dose constraints for the other OARs with sufficient dose margins. The between-group differences in the median NTCP values for the parotid glands and OC were < 3.47% and < 1.7% points, respectively. CONCLUSIONS: The dosimetric profiles of Halcyon VMAT plans were comparable to that of HT, and HL4arc showed better dosimetric profiles than HL2arc for NPCa.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Artrogripose , Colestase , Humanos , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Insuficiência Renal
12.
Cancer Radiother ; 26(6-7): 871-874, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36008262

RESUMO

Anal cancer is considered a rare tumor, accounting for 6 % of digestive cancers and about 2000 new cases per year in France. It is mostly diagnosed at a localized stage. For many years, the standard of care for patients with localized disease is an association with radiotherapy and chemotherapy including Mitomycin C and 5-Fluorouracil. There weren't any major changes in the therapeutic management of these tumors despite several phase III studies. However, there is an improvement in patient prognostic. This can be explained by imaging progress, using magnetic resonance imaging and positron emission tomography-computed tomography, permitting better staging and evaluation of disease. Moreover, irradiation modalities changed because of the development of Intensity Modulated Radiotherapy. Actual research focuses on a more personalized strategy according to tumoral stages. Patients with early-stage tumors are potentially over-treated with a risk of chronic digestive toxicities. Several studies are interested in irradiation de-escalation for these patients. On the other hand, treatment results for patients with advanced tumoral stages are disappointing. It seems relevant to propose a therapeutic intensification for these patients, such as dose escalation, association with new therapies like immunotherapy or induction chemotherapy using taxans given promising results at the metastatic stage.


Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Radioterapia de Intensidade Modulada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Ânus/radioterapia , Carcinoma de Células Escamosas/radioterapia , Quimiorradioterapia/métodos , Fluoruracila , Humanos , Mitomicina , Estadiamento de Neoplasias , Radioterapia de Intensidade Modulada/métodos
13.
Cancer Radiother ; 26(6-7): 794-802, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36028418

RESUMO

During the joint SFRO/SFPM session of the 2019 congress, a state of the art of adaptive radiotherapy announced a strong impact in our clinical practice, in particular with the availability of treatment devices coupled to an MRI system. Three years later, it seems relevant to take stock of adaptive radiotherapy in practice, and especially the "online" strategy because it is indeed more and more accessible with recent hardware and software developments, such as coupled accelerators to a three-dimensional imaging device and algorithms based on artificial intelligence. However, the deployment of this promising strategy is complex because it contracts the usual time scale and upsets the usual organizations. So what do we need to deliver adapted treatment plans with an "online" strategy?


Assuntos
Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Inteligência Artificial , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos
14.
Cancer Radiother ; 26(6-7): 899-904, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36030191

RESUMO

In 1998, an editorial from the International Journal of Radiation Oncology - Biology - Physics (IJROBP) on the occasion of the publication of Phase I by Zelefsky et al. on 3D radiotherapy dose escalation asked the question: "will more prove better?". More than 20 years later, several prospective studies have supported the authors' conclusions, making dose escalation a new standard in prostate cancer. The data from prospective randomized studies were ultimately disappointing in that they failed to show an overall survival benefit from dose escalation. However, there is a clear and consistent benefit in biochemical recurrence-free survival, which must be weighed on an individual patient basis against the potential additional toxicity of dose escalation. Techniques and concepts have become more and more precise, such as intensity modulated irradiation, simultaneous integrated boost, hypofractionated dose-escalation, pelvic irradiation with involved node boost or focal dose-escalation on gross recurrence after prostatectomy. The objective here was to summarize the prospective data on dose escalation in prostate cancer and in particular on recent advances in the field. In 2022, can we finally say that more has proven better?


Assuntos
Braquiterapia , Neoplasias da Próstata , Radioterapia de Intensidade Modulada , Braquiterapia/métodos , Humanos , Masculino , Estudos Prospectivos , Prostatectomia , Neoplasias da Próstata/tratamento farmacológico , Radioterapia de Intensidade Modulada/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
J Clin Oncol ; 40(27): 3115-3119, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35960897

RESUMO

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The purpose of this update was to determine differences in patient-reported chronic toxicity and disease outcomes with intensity-modulated radiation therapy (IMRT) compared with conventional pelvic radiation. Patients with cervical and endometrial cancers who received postoperative pelvic radiation were randomly assigned to conventional radiation therapy (CRT) or IMRT. Toxicity and quality of life were assessed using Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events, Expanded Prostate Cancer Index Composite (EPIC) bowel and urinary domains, and Functional Assessment of Cancer Therapy-General. Between 2012 and 2015, 279 eligible patients were enrolled to the study with a median follow-up of 37.8 months. There were no differences in overall survival (P = .53), disease-free survival (P = .21), or locoregional failure (P = .81). One year after RT, patients in the CRT arm experienced more high-level diarrhea frequency (5.8% IMRT v 15.1% CRT, P = .042) and a greater number had to take antidiarrheal medication two or more times a day (1.2% IMRT v 8.6% CRT, P = .036). At 3 years, women in the CRT arm reported a decline in urinary function, whereas the IMRT arm continued to improve (mean change in EPIC urinary score = 0.5, standard deviation = 13.0, IMRT v -6.0, standard deviation = 14.3, CRT, P = .005). In conclusion, IMRT reduces patient-reported chronic GI and urinary toxicity with no difference in treatment efficacy at 3 years.


Assuntos
Lesões por Radiação , Radioterapia Conformacional , Radioterapia de Intensidade Modulada , Antidiarreicos , Feminino , Humanos , Masculino , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
16.
Phys Med Biol ; 67(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36027876

RESUMO

Objective.To propose a novel moment-based loss function for predicting 3D dose distribution for the challenging conventional lung intensity modulated radiation therapy plans. The moment-based loss function is convex and differentiable and can easily incorporate clinical dose volume histogram (DVH) domain knowledge in any deep learning (DL) framework without computational overhead.Approach.We used a large dataset of 360 (240 for training, 50 for validation and 70 for testing) conventional lung patients with 2 Gy × 30 fractions to train the DL model using clinically treated plans at our institution. We trained a UNet like convolutional neural network architecture using computed tomography, planning target volume and organ-at-risk contours as input to infer corresponding voxel-wise 3D dose distribution. We evaluated three different loss functions: (1) the popular mean absolute error (MAE) loss, (2) the recently developed MAE + DVH loss, and (3) the proposed MAE + moments loss. The quality of the predictions was compared using different DVH metrics as well as dose-score and DVH-score, recently introduced by theAAPM knowledge-based planning grand challenge. Main results.Model with (MAE + moment) loss function outperformed the model with MAE loss by significantly improving the DVH-score (11%,p< 0.01) while having similar computational cost. It also outperformed the model trained with (MAE + DVH) by significantly improving the computational cost (48%) and the DVH-score (8%,p< 0.01).Significance.DVH metrics are widely accepted evaluation criteria in the clinic. However, incorporating them into the 3D dose prediction model is challenging due to their non-convexity and non-differentiability. Moments provide a mathematically rigorous and computationally efficient way to incorporate DVH information in any DL architecture. The code, pretrained models, docker container, and Google Colab project along with a sample dataset are available on our DoseRTX GitHub (https://github.com/nadeemlab/DoseRTX).


Assuntos
Órgãos em Risco , Radioterapia de Intensidade Modulada , Humanos , Redes Neurais de Computação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
17.
Radiat Oncol ; 17(1): 150, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36028862

RESUMO

BACKGROUND: To investigate the performance of a narrow-scope knowledge-based RapidPlan (RP) model for optimisation of intensity-modulated proton therapy (IMPT) and volumetric modulated arc therapy (VMAT) plans applied to patients with pleural mesothelioma. Second, estimate the potential benefit of IMPT versus VMAT for this class of patients. METHODS: A cohort of 82 patients was retrospectively selected; 60 were used to "train" a dose-volume histogram predictive model; the remaining 22 provided independent validation. The performance of the RP models was benchmarked, comparing predicted versus achieved mean and near-to-maximum dose for all organs at risk (OARs) in the training set and by quantitative assessment of some dose-volume metrics in the comparison of the validation RP-based data versus the manually optimised training datasets. Treatment plans were designed for a prescription dose of 44 Gy in 22 fractions (proton doses account for a fixed relative biological effectiveness RBE = 1.1). RESULTS: Training and validation RP-based plans resulted dosimetrically similar for both VMAT and IMPT groups, and the clinical planning aims were met for all structures. The IMPT plans outperformed the VMAT ones for all OARs for the contra-lateral and the mean and low dose regions for the ipsilateral OARs. Concerning the prediction performance of the RP models, the linear regression for the near-to-maximum dose resulted in Dachieved = 1.03Dpredicted + 0.58 and Dachieved = 1.02Dpredicted + 1.46 for VMAT and IMPT, respectively. For the mean dose it resulted: Dachieved = 0.99Dpredicted + 0.34 and Dachieved = 1.05Dpredicted + 0.27 respectively. In both cases, the linear correlation between prediction and achievement is granted with an angular coefficient deviating from unity for less than 5%. Concerning the dosimetric comparison between manual plans in the training cohort and RP-based plans in the validation cohort, no clinical differences were observed for the target volumes in both the VMAT and IMPT groups. Similar consistency was observed for the dose-volume metrics analysed for the OAR. This proves the possibility of achieving the same quality of plans with manual procedures (the training set) or with automated RP-based methods (the validation set). CONCLUSION: Two models were trained and validated for VMAT and IMPT plans for pleural mesothelioma. The RP model performance resulted satisfactory as measured by the agreement between predicted and achieved (after full optimisation) dose-volume metrics. The IMPT plans outperformed the VMAT plans for all the OARs (with different intensities for contra- or ipsilateral structures). RP-based planning enabled the automation of part of the optimisation and the harmonisation of the dose-volume results between training and validation. The IMPT data showed a systematic significant dosimetric advantage over VMAT. In general, using an RP-based approach can simplify the optimisation workflow in these complex treatment indications without impacting the quality of plans.


Assuntos
Mesotelioma , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Órgãos em Risco , Prótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
19.
Technol Cancer Res Treat ; 21: 15330338221119752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35950289

RESUMO

Purpose: We aimed to investigate the effects of different multi-leaf collimator (MLC) speed constraints in volumetric modulated radiotherapy (VMAT) on the robustness of treatment plans for central lung cancer patients. Method and Materials: Twenty patients with central lung tumor who underwent stereotactic body radiotherapy (SBRT) with the VMAT technique at our hospital were included in this retrospective study. The reference plans were created with 3 different MLC speed constraints (Plan A: 0.1 cm/deg., Plan B: 0.3 cm/deg., and Plan C: 0.5 cm/deg.) with a 50-Gy/8Fr, planning target volume (PTV) D95% prescription. In each of these plans, setup errors from 1 to 5 mm were intentionally added in the direction of the central organ at 1-mm intervals (300 plans [20 cases × 3 MLC speeds × 5 error plans] were created in total). Each plan was then calculated by the same beam conditions as each reference plan. The actual average MLC speed and dose difference between the reference plan and the error-added plan were then calculated and compared among the 3 MLC speeds. Results: In the reference plans, the actual average MLC speeds were 0.25 ± 0.04, 0.34 ± 0.07, and 0.39 ± 0.12 cm/deg. for Plan A, Plan B, and Plan C, respectively (P < .05). For PTV and OARs, many dose indices tended to improve as the MLC speed increased, while no significant differences were observed among the 3 MLC speed constraints. However, in assessments of robustness, no significant differences in dose difference were observed among the 3 MLC speed constraints for most of the indices. Conclusions: When necessary, increasing the MLC speed constraint with a priority on improving the quality of the dose distribution is an acceptable approach for central lung cancer patients.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Pulmonares/patologia , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
20.
Radiat Oncol ; 17(1): 146, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35996192

RESUMO

BACKGROUND: Magnetic resonance-guided radiotherapy (MRgRT) utilization is rapidly expanding, driven by advanced capabilities including better soft tissue imaging, continuous intrafraction target visualization, automatic triggered beam delivery, and the availability of on-table adaptive replanning. Our objective was to describe patterns of 0.35 Tesla (T)-MRgRT utilization in Europe and Asia among early adopters of this novel technology. METHODS: Anonymized administrative data from all 0.35T-MRgRT treatment systems in Europe and Asia were extracted for patients who completed treatment from 2015 to 2020. Detailed treatment information was analyzed for all MR-linear accelerators (linac) and -cobalt systems. RESULTS: From 2015 through the end of 2020, there were 5796 completed treatment courses delivered in 46,389 individual fractions. 23.5% of fractions were adapted. Ultra-hypofractionated (UHfx) dose schedules (1-5 fractions) were delivered for 63.5% of courses, with 57.8% of UHfx fractions adapted on-table. The most commonly treated tumor types were prostate (23.5%), liver (14.5%), lung (12.3%), pancreas (11.2%), and breast (8.0%), with increasing compound annual growth rates (CAGRs) in numbers of courses from 2015 through 2020 (pancreas: 157.1%; prostate: 120.9%; lung: 136.0%; liver: 134.2%). CONCLUSIONS: This is the first comprehensive study reporting patterns of utilization among early adopters of a 0.35T-MRgRT system in Europe and Asia. Intrafraction MR image-guidance, advanced motion management, and increasing adoption of on-table adaptive RT have accelerated a transition to UHfx regimens. MRgRT has been predominantly used to treat tumors in the upper abdomen, pelvis and lungs, and increasingly with adaptive replanning, which is a radical departure from legacy radiotherapy practices.


Assuntos
Radiocirurgia , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Aceleradores de Partículas , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos
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