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1.
Eur Arch Otorhinolaryngol ; 280(7): 3345-3352, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36881167

RESUMO

PURPOSE: Early-stage glottic cancer can be treated with radiotherapy only. Modern radiotherapy solutions allow for individualized dose distributions, hypofractionation and sparing of organs at risk. The target volume used to be the entire voice box. This series describe the oncological outcome and toxicity of individualized vocal cord-only hypofractionated radiotherapy for early stage (cT1a-T2 N0). METHODS: Retrospective cohort study with patients treated in a single center between 2014 and 2020. RESULTS: A total of 93 patients were included. Local control rate was 100% for cT1a, 97% for cT1b and 77% for cT2. Risk factor for local recurrence was smoking during radiotherapy. Laryngectomy-free survival was 90% at 5 years. Grade III or higher late toxicity was 3.7%. CONCLUSION: Vocal cord-only hypofractionated radiotherapy appears to be oncologically safe in early-stage glottic cancer. Modern, image-guided radiotherapy led to comparable results as historical series with very limited late toxicity.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Humanos , Prega Vocal/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Neoplasias Laríngeas/cirurgia , Estudos Retrospectivos , Glote/cirurgia , Neoplasias de Cabeça e Pescoço/patologia , Resultado do Tratamento , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias
2.
BMC Cancer ; 22(1): 444, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459142

RESUMO

BACKGROUND: Recurrences remain an important problem in laryngeal squamous cell carcinoma. Little has been described about histological characteristics of the primary laryngeal tumor that may be associated with recurrences. Identifying risk factors for recurrences might help in adapting treatment or follow-up. Using real-life population-based data, we aimed to identify histological features of the primary tumor associated with recurrences and overall survival. MATERIAL AND METHODS: Demographic, clinical and treatment information on all first primary invasive laryngeal tumors diagnosed in 2010-2014 (N = 3705) were extracted from the population-based nationwide Netherlands cancer registry (NCR) and linked to PALGA, the nationwide Dutch pathology registry, to obtain data on histological factors and recurrences. For a random 1502 patients histological information i.e., keratinization, perineural invasion (PNI+), vascular invasion (VI+), growth pattern, degree of differentiation, extracapsular spread (ECS+), cartilage- and bone invasion and extralaryngeal extension, was manually extracted from narrative pathology reports and analyzed for locoregional recurrence and overall survival using cox regression analysis. RESULTS: In total, 299 patients developed a locoregional recurrence and 555 patients died. Keratinization (HR = 0.96 (95%CI: 0.68-1.34) p = 0.79), two or three adverse characteristics (PNI+, VI+, non-cohesive growth) (HR = 1.38 (95% CI: 0.63-3.01) p = 0.42), and ECS+ (HR = 1.38 (95% CI: 0.48-4.02) p = 0.55) were not associated to recurrence. For death, also no significant association was found. CONCLUSION: In this population-based real-life dataset on laryngeal carcinoma in the Netherlands, histological factors were not associated with locoregional recurrences or overall survival, but future studies should investigate the role of these features in treatment decisions.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Laríngeas/patologia , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Países Baixos/epidemiologia , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
3.
BMC Cancer ; 17(1): 208, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28327089

RESUMO

BACKGROUND: In definitive radiation therapy for head and neck cancer, clinically uninvolved cervical lymph nodes are irradiated with a so-called 'elective dose' in order to achieve control of clinically occult metastases. As a consequence of high-resolution diagnostic imaging, occult tumor volume has significantly decreased in the last decades. Since the elective dose is dependent on occult tumor volume, the currently used elective dose may be higher than necessary. Because bilateral irradiation of the neck contributes to dysphagia, xerostomia and hypothyroidism in a dose dependent way, dose de-escalation to these regions can open a window of opportunity to reduce toxicity and improve quality of life after treatment. METHODS: UPGRADE-RT is a multicenter, phase III, single-blinded, randomized controlled trial. Patients to be treated with definitive radiation therapy for a newly diagnosed stage T2-4 N0-2 M0 squamous cell carcinoma of the oropharynx, hypopharynx or larynx are eligible. Exclusion criteria are recurrent disease, oncologic surgery to the head and neck area, concomitant chemotherapy or epidermal growth factor receptor inhibitors. In total, 300 patients will be randomized in a 2:1 ratio to a treatment arm with or without de-escalation of the elective radiation dose and introduction of an intermediate dose-level for selected lymph nodes. Radiation therapy planning FDG-PET/CT-scans will be acquired to guide risk assessment of borderline-sized cervical nodes that can be treated with the intermediate dose level. Treatment will be given with intensity-modulated radiation therapy or volumetric arc therapy with simultaneous-integrated boost using an accelerated fractionation schedule, 33 fractions in 5 weeks. The primary endpoint is 'normalcy of diet' at 1 year after treatment (toxicity). The secondary endpoint is the actuarial rate of recurrence in electively irradiated lymph nodes at 2 years after treatment (safety). DISCUSSION: The objective of the UPGRADE-RT trial is to investigate whether de-escalation of elective radiation dose and the introduction of an intermediate dose-level for borderline sized lymph nodes in the treatment of head and neck cancer will result in less radiation sequelae and improved quality of life after treatment without compromising the recurrence rate in the electively treated neck. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02442375 .


Assuntos
Carcinoma de Células Escamosas/radioterapia , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/radioterapia , Tomografia por Emissão de Pósitrons/métodos , Dosagem Radioterapêutica , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico por imagem , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Método Simples-Cego
4.
Phys Imaging Radiat Oncol ; 29: 100532, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38317852

RESUMO

Background and purpose: Individual elective lymph node irradiation instead of elective neck irradiation is a new concept for head-and-neck cancer (HNC) patients developed for the Magnetic Resonance Image guided linear accelerator (MR-linac). To prepare this, the detectability, volume changes and intra-fraction motion of elective lymph nodes on the MR-linac was assessed. Materials and methods: A total of 15 HNC patients underwent diagnostic pre-treatment MRI. Additionally, two MR-linac scans were obtained with a 10-minute time difference in the first week of radiation treatment. Elective lymph node contours inside lymph node levels (Ib-V) were segmented on the pre-treatment MRI and the MR-linac scans and compared on number and maximal transversal diameter. Intra-fraction motion of elective lymph nodes on the MR-linac was estimated using Center of Mass (COM) distances and incremental isotropic expansion of lymph node segmentations. Results: Of all 679 detected lymph nodes on the pre-treatment MRI, eight lymph nodes were not detectable on the first MR-linac scan and 16 new lymph nodes were detected. Lymph node diameters between the pre-treatment MRI scan and the MR-linac scan varied from -0.19 to + 0.13 mm. COM distances varied from 1.2 to 1.7 mm and lymph node contours had to be expanded with 3 mm. Conclusions: Nearly all elective lymph nodes were detectable on the 1.5T MR-linac scan with no major changes in target volumes compared to the pre-treatment MRI. Simulated intra-fraction motion during the MR-linac scans was smaller than the 5-mm margin that will be used in the first elective lymph node radiation treatment.

5.
Radiother Oncol ; 194: 110182, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38403024

RESUMO

OBJECTIVE: This study aims to determine the added value of a geometrically accurate diffusion-weighted (DW-) MRI sequence on the accuracy of gross tumor volume (GTV) delineations, using pathological tumor delineations as a ground truth. METHODS: Sixteen patients with laryngeal or hypopharyngeal carcinoma were included. After total laryngectomy, the specimen was cut into slices. Photographs of these slices were stacked to create a 3D digital specimen reconstruction, which was registered to the in vivo imaging. The pathological tumor (tumorHE) was delineated on the specimen reconstruction. Six observers delineated all tumors twice: once with only anatomical MR imaging, and once (a few weeks later) when DW sequences were also provided. The majority voting delineation of session one (GTVMRI) and session two (GTVDW-MRI), as well as the clinical target volumes (CTVs), were compared to the tumorHE. RESULTS: The mean tumorHE volume was 11.1 cm3, compared to a mean GTVMRI volume of 18.5 cm3 and a mean GTVDW-MRI volume of 15.7 cm3. The median sensitivity (tumor coverage) was comparable between sessions: 0.93 (range: 0.61-0.99) for the GTVMRI and 0.91 (range: 0.53-1.00) for the GTVDW-MRI. The CTV volume also decreased when DWI was available, with a mean CTVMR of 47.1 cm3 and a mean CTVDW-MRI of 41.4 cm3. Complete tumor coverage was achieved in 15 and 14 tumors, respectively. CONCLUSION: GTV delineations based on anatomical MR imaging tend to overestimate the tumor volume. The availability of the geometrically accurate DW sequence reduces the GTV overestimation and thereby CTV volumes, while maintaining acceptable tumor coverage.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Hipofaríngeas , Neoplasias Laríngeas , Humanos , Neoplasias Hipofaríngeas/diagnóstico por imagem , Neoplasias Hipofaríngeas/patologia , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Masculino , Idoso , Pessoa de Meia-Idade , Feminino , Carga Tumoral , Laringectomia
6.
Clin Transl Radiat Oncol ; 39: 100574, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36686561

RESUMO

Introduction: The long-term complication rate in head-and-neck squamous cell carcinoma (HNSCC) patients caused by radiotherapy (RT) can be decreased by restricting elective neck irradiation (ENI) from large adjacent lymph node levels to only individual elective lymph nodes. The primary objective of this study is to treat the first HNSCC patients with individual elective lymph node irradiation by means of a Magnetic Resonance-linac (MR-linac) in order to assess the feasibility. Methods and analysis: In this phase I feasibility study, 20 patients will be included with histologically proven cT2-4N0-1M0 HNSCC originating from the oropharynx, hypopharynx or larynx, planned for treatment with primary radiotherapy and bilateral elective neck irradiation (ENI). Patients will be treated with 35 fractions in six weeks, according to the DAHANCA schedule. Individual lymph nodes inside the conventional lymph node levels will be categorized in low-risk, intermediate-risk and high-risk based on cytology, histology and imaging parameters. Low-risk and intermediate-risk lymph nodes will irradiated in 20 and 23 fractions respectively, with a fraction dose of 2 Gy (=40/46 Gy EQD2). The high-risk lymph nodes and the primary tumor will be irradiated in 35 fractions of 2 Gy (=70 Gy equivalent dose in 2 Gy fractions (EQD2)). To limit treatment burden, 20 fractions will be applied on the MR-linac. The last 15 fractions (sequential boost at the primary tumor, intermediate-risk and high-risk lymph nodes) will be applied on a conventional linear accelerator. The main study endpoint is the percentage of fractions that are successfully completed on the MR-linac. Ethics and dissemination: With individual elective lymph node irradiation we expect less toxicity and a better quality of life for HNSCC patients. However, as the treatment time on the MR-linac will be longer (30-45 vs 15 min per fraction) we need to examine if patients can endure this new treatment concept.

7.
Front Radiol ; 2: 1033521, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37492674

RESUMO

Background and purpose: To decrease the impact of radiotherapy to healthy tissues in the head and neck region, we propose to restrict the elective neck irradiation to elective lymph nodes at risk of containing micro metastases instead of the larger lymph node volumes. To assess whether this new concept is achievable in the clinic, we determined the number, volume changes and displacement of elective lymph nodes during the course of radiotherapy. Materials and methods: MRI scans of 10 head and neck cancer (HNC) patients were acquired before radiotherapy and in week 2, 3, 4 and 5 during radiotherapy. The weekly delineations of elective lymph nodes inside the lymph node levels (Ib/II/III/IVa/V) were rigidly registered and analyzed regarding number and volume. The displacement of elective lymph nodes was determined by center of mass (COM) distances, vector-based analysis and the isotropic contour expansion of the lymph nodes of the pre-treatment scan or the scan of the previous week in order to geographically cover 95% of the lymph nodes in the scans of the other weeks. Results: On average, 31 elective lymph nodes in levels Ib-V on each side of the neck were determined. This number remained constant throughout radiotherapy in most lymph node levels. The volume of the elective lymph nodes reduced significantly in all weeks, up to 50% in week 5, compared to the pre-treatment scan. The largest median COM displacements were seen in level V, for example 5.2 mm in week 5 compared to the pre-treatment scan. The displacement of elective lymph nodes was mainly in cranial direction. Geographical coverage was obtained when the lymph node volumes were expanded with 7 mm in case the pre-treatment scan was used and 6.5 mm in case the scan of the previous week was used. Conclusion: Elective lymph nodes of HNC patients remained visible on MRI and decreased in size during radiotherapy. The displacement of elective lymph nodes differ per lymph node level and were mainly directed cranially. Weekly adaptation does not seem to improve coverage of elective lymph nodes. Based on our findings we expect elective lymph node irradiation is achievable in the clinic.

8.
Cancers (Basel) ; 14(12)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35740691

RESUMO

In recent years, MRI-guided radiotherapy (MRgRT) has taken an increasingly important position in image-guided radiotherapy (IGRT). Magnetic resonance imaging (MRI) offers superior soft tissue contrast in anatomical imaging compared to computed tomography (CT), but also provides functional and dynamic information with selected sequences. Due to these benefits, in current clinical practice, MRI is already used for target delineation and response assessment in patients with head and neck squamous cell carcinoma (HNSCC). Because of the close proximity of target areas and radiosensitive organs at risk (OARs) during HNSCC treatment, MRgRT could provide a more accurate treatment in which OARs receive less radiation dose. With the introduction of several new radiotherapy techniques (i.e., adaptive MRgRT, proton therapy, adaptive cone beam computed tomography (CBCT) RT, (daily) adaptive radiotherapy ensures radiation dose is accurately delivered to the target areas. With the integration of a daily adaptive workflow, interfraction changes have become visible, which allows regular and fast adaptation of target areas. In proton therapy, adaptation is even more important in order to obtain high quality dosimetry, due to its susceptibility for density differences in relation to the range uncertainty of the protons. The question is which adaptations during radiotherapy treatment are oncology safe and at the same time provide better sparing of OARs. For an optimal use of all these new tools there is an urgent need for an update of the target definitions in case of adaptive treatment for HNSCC. This review will provide current state of evidence regarding adaptive target definition using MR during radiotherapy for HNSCC. Additionally, future perspectives for adaptive MR-guided radiotherapy will be discussed.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36090011

RESUMO

Background and purpose: Online adaptive MR-guided treatment planning workflows facilitate daily contour adaptation to the actual anatomy. Allocating contour adaptation to radiation therapists (RTTs) instead of radiation oncologists (ROs) might allow for increasing workflow efficiency. This study investigates conformity of adapted target contours provided by dedicated RTTs and ROs. Materials and methods: In a simulated online procedure, 6 RTTs and 6 ROs recontoured targets and organs at risk (OAR) in prostate cancer (n = 2), rectal cancer (n = 2) and lymph node-oligometastases (n = 2) cases. RTTs gained contouring competence beforehand by following a specific in-house training program. For all target contours and the reference delineations volumetric differences were determined and Dice similarity coefficient (DSC), conformity index (CI) and generalized CI were calculated. Delineation time and -confidence were registered for targets and OAR. Impact of contour adaptation on treatment plan quality was investigated. Results: Delineation conformity was generally high with DSC, CI and generalized CI values in the range of 0.81-0.94, 0.87-0.95 and 0.63-0.85 for prostate cancer, rectal cancer and LN-oligometastasis, respectively. Target volumes were comparable for both, RTTs and ROs. Time needed and confidence in contour adaptation was comparable as well. Treatment plans derived with adapted contours did not violate dose volume constrains as used in clinical routine. Conclusion: After tumor site specific training, daily contour adaptations as needed in adaptive online radiotherapy workflows can be accurately performed by RTTs. Conformity of the derived contours is high and comparable to contours as provided by ROs.

10.
Phys Imaging Radiat Oncol ; 20: 76-81, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35169639

RESUMO

BACKGROUND AND PURPOSE: Conventional elective neck irradiation (ENI) in head and neck cancer consists of radiotherapy (RT) to the regional lymph node (LN) levels contoured on computed tomography. Hybrid Magnetic Resonance (MR) - RT modalities, such as combined magnetic resonance imaging - linear accelerators (MRLs), might enable new ENI strategies in which individual non-suspect lymph nodes (i-LNs) are targeted. In this treatment planning study, new MR-based strategies targeting i-LNs (i-ENI) were compared to conventional treatment. MATERIALS AND METHODS: All i-LNs were delineated on MR images of ten retrospectively selected patients with T2-4aN0M0 laryngeal cancer. Three strategies were considered. Strategy A: Conventional ENI delivered with a conventional linear accelerator (35x 1.55 Gy). Strategy B: MRL-based i-ENI (35x 1.55 Gy) to the individual lymph nodes including a background dose to the conventional elective neck volumes (35x 1.03 Gy). Strategy C: Same as Strategy B, but without background dose. In all plans the dose prescription to the primary tumor was 35x 2 Gy. Mean dose (D mean) reductions in the organs at risk (OAR) were compared using the Wilcoxon signed rank test. RESULTS: Compared to conventional ENI (strategy A), significant D mean reductions of 6.0 Gy and 8.0 Gy were observed in the submandibular glands, of 9.4 Gy and 13 Gy in the carotid arteries and of 9.9 Gy and 19.4 Gy in the thyroid for strategy B and C, respectively. Large inter-patient variations of D mean reductions were observed in all OARs. CONCLUSION: MRL-based i-ENI is a new promising concept that could reduce the mean dose to OARs in the neck significantly for patients with laryngeal cancer.

11.
Radiother Oncol ; 142: 107-114, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31439447

RESUMO

BACKGROUND AND PURPOSE: Multimodality imaging including 18F-FDG-PET has improved the detection threshold of nodal metastases in head and neck squamous cell carcinoma (HNSCC). The aim of this retrospective analysis is to investigate the impact of FDG-PET/CT-based nodal target volume definition (FDG-PET/CT-based NTV) on radiotherapy outcomes, compared to conventional CT-based nodal target volume definition (CT-based NTV). MATERIALS AND METHODS: Six-hundred-thirty-three patients treated for HNSCC with definitive (chemo)radiotherapy using IMRT/VMAT techniques between 2008 and 2017 were analyzed. FDG-PET/CT-based NTV was performed in 46% of the patients. The median follow-up was 31 months. Diagnostic imaging depicting the regional recurrence was co-registered with the initial CT-scan to reconstruct the exact site of the recurrence. Multivariate Cox regression analysis was performed to identify variables associated with radiotherapy outcome. RESULTS: FDG-PET/CT-based NTV improved control of disease in the CTVelective-nodal (HR: 0.33, p = 0.026), overall regional control (HR: 0.62, p = 0.027) and overall survival (HR: 0.71, p = 0.033) compared to CT-based NTV. The risk for recurrence in the CTVelective-nodal was increased in case of synchronous local recurrence of the primary tumor (HR: 12.4, p < 0.001). CONCLUSION: FDG-PET/CT-based NTV significantly improved control of disease in the CTVelective-nodal, overall regional control and overall survival compared to CT-based NTV. A significant proportion of CTVelective-nodal recurrences are potentially new nodal manifestations from a synchronous local recurrent primary tumor. These results support the concept of target volume transformation and give an indication of the potential of FDG-PET to guide gradual radiotherapy dose de-escalation in elective neck treatment in HNSCC.


Assuntos
Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/terapia , Planejamento da Radioterapia Assistida por Computador/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Quimiorradioterapia , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Modelos de Riscos Proporcionais , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Taxa de Sobrevida
12.
Int J Radiat Oncol Biol Phys ; 105(3): 514-524, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31306734

RESUMO

PURPOSE: To benchmark and improve, through means of a targeted intervention, the quality of intensity modulated radiation therapy treatment planning for locally advanced head and neck cancer (HNC) in the Netherlands. The short and long-term impact of this intervention was assessed. METHODS AND MATERIALS: A delineated computed tomography-scan of an oropharynx HNC case was sent to all 15 Dutch radiation therapy centers treating HNC. Aims for planning target volume and organ-at-risk (OAR) dosimetry were established by consensus. Each center generated a treatment plan. In a targeted intervention, OAR sparing of all plans was discussed, and centers with the best OAR sparing shared their planning strategies. Impact of the intervention was assessed by (1) short-term (half a year after intervention) replanning of the original case and (2) long-term (1 and 3 years after intervention) planning of new cases. RESULTS: Benchmarking revealed substantial difference in OAR doses. Initial mean doses were 22 Gy (range, 15-31 Gy), 35 Gy (18-49 Gy), and 37 Gy (20-46 Gy) for the contralateral parotid gland, contralateral submandibular gland, and combined swallowing structures, respectively. Replanning after targeted intervention significantly reduced mean doses and variation, but clinically relevant differences still remained: 18 Gy (14-22 Gy), 28 Gy (17-45 Gy), and 29 Gy (18-39 Gy), respectively. One and 3 years later the variation remained stable. CONCLUSIONS: Despite many years of HNC intensity modulated radiation therapy experience, initial treatment plans showed surprisingly large variations. The simple targeted intervention used in this analysis improved OAR sparing, and its impact was durable; however, fairly large dose differences still continue to exist. Additional work is needed to understand these variations and to minimize them. A national radiation oncology platform can be instrumental for developing and maintaining high-quality planning protocols.


Assuntos
Benchmarking/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia de Intensidade Modulada/normas , Benchmarking/normas , Pesquisas sobre Atenção à Saúde , Humanos , Países Baixos , Tratamentos com Preservação do Órgão/normas , Órgãos em Risco/diagnóstico por imagem , Glândula Parótida/diagnóstico por imagem , Glândula Parótida/efeitos da radiação , Músculos Faríngeos/diagnóstico por imagem , Músculos Faríngeos/efeitos da radiação , Melhoria de Qualidade , Doses de Radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Glândula Submandibular/diagnóstico por imagem , Glândula Submandibular/efeitos da radiação , Fatores de Tempo , Língua/diagnóstico por imagem , Língua/efeitos da radiação , Neoplasias Tonsilares/diagnóstico por imagem , Neoplasias Tonsilares/radioterapia
13.
Med Phys ; 46(9): 4095-4104, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31206701

RESUMO

PURPOSE: To develop and evaluate a patch-based convolutional neural network (CNN) to generate synthetic computed tomography (sCT) images for magnetic resonance (MR)-only workflow for radiotherapy of head and neck tumors. A patch-based deep learning method was chosen to improve robustness to abnormal anatomies caused by large tumors, surgical excisions, or dental artifacts. In this study, we evaluate whether the generated sCT images enable accurate MR-based dose calculations in the head and neck region. METHODS: We conducted a retrospective study on 34 patients with head and neck cancer who underwent both CT and MR imaging for radiotherapy treatment planning. To generate the sCTs, a large field-of-view T2-weighted Turbo Spin Echo MR sequence was used from the clinical protocol for multiple types of head and neck tumors. To align images as well as possible on a voxel-wise level, CT scans were nonrigidly registered to the MR (CTreg ). The CNN was based on a U-net architecture and consisted of 14 layers with 3 × 3 × 3 filters. Patches of 48 × 48 × 48 were randomly extracted and fed into the training. sCTs were created for all patients using threefold cross validation. For each patient, the clinical CT-based treatment plan was recalculated on sCT using Monaco TPS (Elekta). We evaluated mean absolute error (MAE) and mean error (ME) within the body contours and dice scores in air and bone mask. Also, dose differences and gamma pass rates between CT- and sCT-based plans inside the body contours were calculated. RESULTS: sCT generation took 4 min per patient. The MAE over the patient population of the sCT within the intersection of body contours was 75 ± 9 Hounsfield Units (HU) (±1 SD), and the ME was 9 ± 11 HU. Dice scores of the air and bone masks (CTreg vs sCT) were 0.79 ± 0.08 and 0.70 ± 0.07, respectively. Dosimetric analysis showed mean deviations of -0.03% ± 0.05% for dose within the body contours and -0.07% ± 0.22% inside the >90% dose volume. Dental artifacts obscuring the CT could be circumvented in the sCT by the CNN-based approach in combination with Turbo Spin Echo (TSE) magnetic resonance imaging (MRI) sequence that typically is less prone to susceptibility artifacts. CONCLUSIONS: The presented CNN generated sCTs from conventional MR images without adding scan time to the acquisition. Dosimetric evaluation suggests that dose calculations performed on the sCTs are accurate, and can therefore be used for MR-only radiotherapy treatment planning of the head and neck.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Tomografia Computadorizada por Raios X , Humanos , Imageamento por Ressonância Magnética , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada
14.
Oral Oncol ; 42(2): 131-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16146705

RESUMO

The objective of this study was to investigate the prognostic significance of the hemoglobin (Hb) levels at different timepoints in locally advanced squamous cell carcinoma of the head and neck (SCCHN). Included were 111 patients. The hemoglobin levels were assessed before surgery (PreS-Hb), between surgery and radiotherapy (HbAAC), before postoperative radiotherapy (PreRT-Hb) and at the end of radiotherapy (EndRT-Hb). HbAAC takes into account the duration of anemia during the interval between surgery and radiotherapy. Higher HbAAC corresponds with lower Hb levels. Five year locoregional control (LRC) among patients with HbAAC > or = median was 72% and significantly worse as compared to the 88% in case of HbAAC < median (p = 0.0097). Multivariate analysis for LRC showed that the HbAAC was a prognostic factor. Overall survival (OS) after 3 years was 77% in case of HbAAC < median and 34% in case of HbAAC > or = median (p < 0.0002). Multivariate analysis for OS showed that the PreS-Hb and HbAAC were prognostic factors. Hb level between surgery and radiotherapy is an important prognostic factor for both LRC and OS among patients with SCCHN treated with surgery and postoperative radiotherapy.


Assuntos
Anemia/complicações , Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Hemoglobinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/complicações , Hipóxia Celular , Métodos Epidemiológicos , Feminino , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Período Pós-Operatório , Prognóstico , Radioterapia Adjuvante , Resultado do Tratamento
15.
Eur J Cancer ; 49(15): 3202-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23867129

RESUMO

Accelerated radiotherapy (AR) improves the poor prognosis associated with epidermal growth factor receptor (EGFR) overexpression frequently seen in head and neck carcinomas. Combining AR with carbogen and nicotinamide (ARCON) counteracts enhanced tumour cell proliferation- and hypoxia-related radioresistance. The purpose of this study was to investigate if EGFR expression levels are associated with response to ARCON in patients with carcinoma of the larynx. Patients (N=272) with advanced stage larynx carcinoma were randomised between AR alone and ARCON. Paraffin-embedded biopsies from these patients were processed for immunohistochemical staining of EGFR. EGFR fraction was quantitated by automated image analysis and related to clinical outcome. A large variation was observed in EGFR fraction between tumours with expression levels ranging from 0 to 0.93 (median fraction 0.4). No difference in 5-year locoregional control was found between low and high EGFR expressing tumours in the AR arm (69% versus 75%), which is in line with the established effect of AR in EGFR overexpressing tumours. There was, however, a significant association in the ARCON arm: patients with low EGFR levels had a better 5-year locoregional control (88% versus 72% p=0.02) and disease-specific survival (92% versus 77% p=0.01). ARCON improved locoregional control relative to AR only in patients with low EGFR expression (hazard ratio (HR) 0.34 p=0.009). In conclusion, only in tumours with a low EGFR fraction, adding hypoxia modification to AR has an additive beneficial effect on outcome. EGFR expression is a predictive biomarker for the selection of patients that will or will not respond to ARCON.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Hipóxia Celular/fisiologia , Receptores ErbB/biossíntese , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Receptores ErbB/metabolismo , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/enzimologia , Neoplasias Laríngeas/patologia , Pessoa de Meia-Idade , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Análise de Sobrevida , Resultado do Tratamento
16.
Int J Radiat Oncol Biol Phys ; 78(3): 682-8, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20188492

RESUMO

PURPOSE: The purpose was to evaluate the contralateral nodal control (CLNC) in postoperative patients with oral and oropharyngeal cancer treated with ipsilateral irradiation of the neck and primary site. Late radiation-induced morbidity was also evaluated. METHODS AND MATERIALS: The study included 123 patients with well-lateralized squamous cell carcinomas treated with surgery and unilateral postoperative irradiation. Most patients had tumors of the gingiva (41%) or buccal mucosa (21%). The majority of patients underwent surgery of the ipsilateral neck (n = 102 [83%]). The N classification was N0 in 73 cases (59%), N1 or N2a in 23 (19%), and N2b in 27 cases (22%). RESULTS: Contralateral metastases developed in 7 patients (6%). The 5-year actuarial CLNC was 92%. The number of lymph node metastases was the only significant prognostic factor with regard to CLNC. The 5-year CLNC was 99% in N0 cases, 88% in N1 or N2a cases, and 73% in N2b cases (p = 0.008). Borderline significance (p = 0.06) was found for extranodal spread. Successful salvage could be performed in 71% of patients with contralateral metastases. The prevalence of Grade 2 or higher xerostomia was 2.6% at 5 years. CONCLUSIONS: Selected patients with oral or oropharyngeal carcinoma treated with primary surgery and postoperative ipsilateral radiotherapy have a very high CLNC with a high probability of successful salvage in case of contralateral metastases. However, bilateral irradiation should be applied in case of multiple lymph node metastases in the ipsilateral neck, particularly in the presence of extranodal spread. The incidence of radiation-induced morbidity is considerably lower as observed after bilateral irradiation.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Irradiação Linfática/métodos , Neoplasias Bucais/radioterapia , Neoplasias Orofaríngeas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/cirurgia , Seguimentos , Humanos , Incidência , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Países Baixos , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/cirurgia , Lesões por Radiação/epidemiologia , Lesões por Radiação/patologia , Dosagem Radioterapêutica , Terapia de Salvação , Neoplasias da Língua/mortalidade , Neoplasias da Língua/patologia , Neoplasias da Língua/radioterapia , Neoplasias da Língua/cirurgia , Xerostomia/prevenção & controle
17.
Int J Radiat Oncol Biol Phys ; 74(1): 1-8, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19111400

RESUMO

PURPOSE: The purpose of this study was to compare intensity-modulated radiation therapy (IMRT) and three-dimensional conventional radiotherapy (3D-CRT) with regard to patient-rated xerostomia, Radiation Therapy Oncology Group (RTOG) acute and late xerostomia and health-related quality of life (HRQoL) among patients with head and neck squamous cell carcinoma (HNSCC). METHODS AND MATERIALS: Included were 241 patients with HNSCC treated with bilateral irradiation +/- chemotherapy. Since 2000, all patients treated with HNSCC were included in a program, which prospectively assessed acute and late morbidity according to the RTOG and HRQoL on a routine basis at regular intervals. Before October 2004, all patients were treated with 3D-CRT (N = 150). After clinical implementation in October 2004, 91 patients received IMRT. In this study, the differences regarding RTOG toxicity, xerostomia, and other items of HRQoL were analyzed. RESULTS: The use of IMRT resulted in a significant reduction of the mean dose of the parotid glands (27 Gy vs. 43 Gy (p < 0.001). During radiation, Grade 2 RTOG xerostomia was significantly less with IMRT than with 3D-CRT. At 6 months, the prevalence of patient-rated moderate to severe xerostomia and Grade 2 or higher RTOG xerostomia was significantly lower after IMRT versus 3D-CRT. Treatment with IMRT also had a positive effect on several general and head and neck cancer-specific HRQoL dimensions. CONCLUSIONS: IMRT results in a significant reduction of patient- and observer-rated xerostomia, as well as other head and neck symptoms, compared with standard 3D-CRT. These differences translate into a significant improvement of the more general dimensions of HRQoL.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Nível de Saúde , Qualidade de Vida , Radioterapia Conformacional/efeitos adversos , Xerostomia/etiologia , Doença Aguda , Adolescente , Adulto , Idoso , Análise de Variância , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Parótida/efeitos da radiação , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Glândula Submandibular/efeitos da radiação , Carga Tumoral , Adulto Jovem
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