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1.
J Eur Acad Dermatol Venereol ; 38(5): 945-953, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38158385

RESUMO

BACKGROUND: Deep-learning convolutional neural networks (CNNs) have outperformed even experienced dermatologists in dermoscopic melanoma detection under controlled conditions. It remains unexplored how real-world dermoscopic image transformations affect CNN robustness. OBJECTIVES: To investigate the consistency of melanoma risk assessment by two commercially available CNNs to help formulate recommendations for current clinical use. METHODS: A comparative cohort study was conducted from January to July 2022 at the Department of Dermatology, University Hospital Basel. Five dermoscopic images of 116 different lesions on the torso of 66 patients were captured consecutively by the same operator without deliberate rotation. Classification was performed by two CNNs (CNN-1/CNN-2). Lesions were divided into four subgroups based on their initial risk scoring and clinical dignity assessment. Reliability was assessed by variation and intraclass correlation coefficients. Excisions were performed for melanoma suspicion or two consecutively elevated CNN risk scores, and benign lesions were confirmed by expert consensus (n = 3). RESULTS: 117 repeated image series of 116 melanocytic lesions (2 melanomas, 16 dysplastic naevi, 29 naevi, 1 solar lentigo, 1 suspicious and 67 benign) were classified. CNN-1 demonstrated superior measurement repeatability for clinically benign lesions with an initial malignant risk score (mean variation coefficient (mvc): CNN-1: 49.5(±34.3)%; CNN-2: 71.4(±22.5)%; p = 0.03), while CNN-2 outperformed for clinically benign lesions with benign scoring (mvc: CNN-1: 49.7(±22.7)%; CNN-2: 23.8(±29.3)%; p = 0.002). Both systems exhibited lowest score consistency for lesions with an initial malignant risk score and benign assessment. In this context, averaging three initial risk scores achieved highest sensitivity of dignity assessment (CNN-1: 94%; CNN-2: 89%). Intraclass correlation coefficients indicated 'moderate'-to-'good' reliability for both systems (CNN-1: 0.80, 95% CI:0.71-0.87, p < 0.001; CNN-2: 0.67, 95% CI:0.55-0.77, p < 0.001). CONCLUSIONS: Potential user-induced image changes can significantly influence CNN classification. For clinical application, we recommend using the average of three initial risk scores. Furthermore, we advocate for CNN robustness optimization by cross-validation with repeated image sets. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04605822).


Assuntos
Dermoscopia , Melanoma , Redes Neurais de Computação , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico por imagem , Melanoma/patologia , Dermoscopia/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Estudos Prospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto , Idoso , Medição de Risco , Aprendizado Profundo , Síndrome do Nevo Displásico/patologia , Síndrome do Nevo Displásico/diagnóstico por imagem
2.
Sci Rep ; 10(1): 10530, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601333

RESUMO

The purpose of this study was to construct and characterize iron oxide nanoparticles (IONPCO) for intracellular delivery of the anthracycline doxorubicin (DOX; IONPDOX) in order to induce tumor cell inactivation. More than 80% of the loaded drug was released from IONPDOX within 24 h (100% at 70 h). Efficient internalization of IONPDOX and IONPCO in HeLa cells occurred through pino- and endocytosis, with both IONP accumulating in a perinuclear pattern. IONPCO were biocompatible with maximum 27.9% ± 6.1% reduction in proliferation 96 h after treatment with up to 200 µg/mL IONPCO. Treatment with IONPDOX resulted in a concentration- and time-dependent decrease in cell proliferation (IC50 = 27.5 ± 12.0 µg/mL after 96 h) and a reduced clonogenic survival (surviving fraction, SF = 0.56 ± 0.14; versus IONPCO (SF = 1.07 ± 0.38)). Both IONP constructs were efficiently internalized and retained in the cells, and IONPDOX efficiently delivered DOX resulting in increased cell death vs IONPCO.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Endocitose/efeitos dos fármacos , Nanopartículas de Magnetita/administração & dosagem , Transporte Biológico/efeitos dos fármacos , Células HeLa , Humanos
3.
Breast Cancer Res Treat ; 168(3): 739-744, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29335922

RESUMO

PURPOSE: Mastectomy is the standard procedure in patients with in-breast tumor recurrence (IBTR) or breast cancer after irradiation of the chest due to Hodgkin's disease. In certain cases a second breast conserving surgery (BCS) in combination with intraoperative radiotherapy (IORT) is possible. To date, data concerning BCS in combination with IORT in pre-irradiated patients are limited. This is the first pooled analysis of this special indication with a mature follow-up of 5 years. METHODS: Patients with IBTR after external beam radiotherapy (EBRT; treated in two centers) for breast cancer were included. Patients with previous EBRT including the breast tissue due to other diseases were also included. IORT was performed with the Intrabeam™-device using low kV X-rays. Clinical data including outcome for all patients and toxicity for a representative cohort (LENT-SOMA scales) were obtained. Statistical analyses were done including Kaplan-Meier estimates for local recurrence, distant metastasis and overall survival. RESULTS: A total of 41 patients were identified (39 patients with IBTR, 2 with Hodgkin`s disease in previous medical history). Median follow-up was 58 months (range 4-170). No grade 3/4 acute toxicity occurred within 9 weeks. Local recurrence-free survival rate was 89.9% and overall survival was 82.7% at 5 years. Seven patients developed metastasis within the whole follow-up. CONCLUSIONS: BCS in combination with IORT in IBTR in pre-irradiated patients is a feasible method to avoid mastectomy with a low risk of side effects and an excellent local control and good overall survival.


Assuntos
Neoplasias da Mama/cirurgia , Mama/cirurgia , Recidiva Local de Neoplasia/cirurgia , Radioterapia Adjuvante/métodos , Adulto , Idoso , Mama/patologia , Mama/efeitos da radiação , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Terapia Combinada/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Cuidados Intraoperatórios , Mastectomia , Mastectomia Segmentar/efeitos adversos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia
4.
Strahlenther Onkol ; 192(11): 815-819, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27380001

RESUMO

OBJECTIVE: The Gamma Knife Icon (Elekta AB, Stockholm, Sweden) allows frameless stereotactic treatment using a combination of cone beam computer tomography (CBCT), a thermoplastic mask system, and an infrared-based high-definition motion management (HDMM) camera system for patient tracking during treatment. We report on the first patient with meningioma at the left petrous bone treated with adaptive fractionated stereotactic radiotherapy (a-gkFSRT). METHODS: The first patient treated with Gamma Knife Icon at our institute received MR imaging for preplanning before treatment. For each treatment fraction, a daily CBCT was performed to verify the actual scull/tumor position. The system automatically adapted the planned shot positions to the daily position and recalculated the dose distribution (online adaptive planning). During treatment, the HDMM system recorded the intrafractional patient motion. Furthermore, the required times were recorded to define a clinical treatment slot. RESULTS: Total treatment time was around 20 min. Patient positioning needed 0.8 min, CBCT positioning plus acquisition 1.65 min, CT data processing and adaptive planning 2.66 min, and treatment 15.6 min. The differences for the five daily CBCTs compared to the reference are for rotation: -0.59 ± 0.49°/0.18 ± 0.20°/0.05 ± 0.36° and for translation: 0.94 ± 0.52 mm/-0.08 ± 0.08 mm/-1.13 ± 0.89 mm. Over all fractions, an intrafractional movement of 0.13 ± 0.04 mm was observed. CONCLUSION: The Gamma Knife Icon allows combining the accuracy of the stereotactic Gamma Knife system with the flexibility of fractionated treatment with the mask system and CBCT. Furthermore, the Icon system introduces a new online patient tracking system to the clinical routine. The interfractional accuracy of patient positioning was controlled with a thermoplastic mask and CBCT.


Assuntos
Tomografia Computadorizada de Feixe Cônico/instrumentação , Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Radiocirurgia/instrumentação , Planejamento da Radioterapia Assistida por Computador/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Idoso , Tomografia Computadorizada de Feixe Cônico/métodos , Fracionamento da Dose de Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Integração de Sistemas , Resultado do Tratamento
5.
Strahlenther Onkol ; 192(4): 199-208, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26931319

RESUMO

OBJECTIVE: To update the practical guidelines for radiotherapy of patients with locoregional breast cancer recurrences based on the current German interdisciplinary S3 guidelines 2012. METHODS: A comprehensive survey of the literature using the search phrases "locoregional breast cancer recurrence", "chest wall recurrence", "local recurrence", "regional recurrence", and "breast cancer" was performed, using the limits "clinical trials", "randomized trials", "meta-analysis", "systematic review", and "guidelines". CONCLUSIONS: Patients with isolated in-breast or regional breast cancer recurrences should be treated with curative intent. Mastectomy is the standard of care for patients with ipsilateral breast tumor recurrence. In a subset of patients, a second breast conservation followed by partial breast irradiation (PBI) is an appropriate alternative to mastectomy. If a second breast conservation is performed, additional irradiation should be mandatory. The largest reirradiation experience base exists for multicatheter brachytherapy; however, prospective clinical trials are needed to clearly define selection criteria, long-term local control, and toxicity. Following primary mastectomy, patients with resectable locoregional breast cancer recurrences should receive multimodality therapy including systemic therapy, surgery, and radiation +/- hyperthermia. This approach results in high local control rates and long-term survival is achieved in a subset of patients. In radiation-naive patients with unresectable locoregional recurrences, radiation therapy is mandatory. In previously irradiated patients with a high risk of a second local recurrence after surgical resection or in patients with unresectable recurrences, reirradiation should be strongly considered. Indication and dose concepts depend on the time interval to first radiotherapy, presence of late radiation effects, and concurrent or sequential systemic treatment. Combination with hyperthermia can further improve tumor control. In patients with isolated axillary or supraclavicular recurrence, durable disease control is best achieved with multimodality therapy including surgery and radiotherapy. Radiation therapy significantly improves local control and should be applied whenever feasible.


Assuntos
Neoplasias da Mama/radioterapia , Carcinoma Ductal/radioterapia , Carcinoma Intraductal não Infiltrante/radioterapia , Recidiva Local de Neoplasia/radioterapia , Terapia Combinada , Comportamento Cooperativo , Feminino , Alemanha , Humanos , Comunicação Interdisciplinar , Mastectomia , Radioterapia Adjuvante , Reoperação , Retratamento
6.
Urologe A ; 55(3): 326-32, 2016 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-26895435

RESUMO

BACKGROUND: Radiation therapy is an established cornerstone in the treatment of prostate cancer. Significant advances in the techniques and therapeutic concepts have been made in recent decades. OBJECTIVES: The objective of this article is to provide an overview of current standards of care and recent technical and conceptional developments. CONCLUSIONS: Three-dimensional conformal radiotherapy has long been the standard of care for percutaneous radiotherapy. The development of intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT) have increased the precision of treatment, thus, reducing side effects and allowing dose escalation. LDR (low dose rate) and HDR (high dose rate) brachytherapy alone or in combination are a treatment option in localized prostate cancer with a distinct side effect profile. The roles of proton therapy and stereotactic radiotherapy should be further investigated in prospective trials.


Assuntos
Braquiterapia/normas , Oncologia/normas , Guias de Prática Clínica como Assunto , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Radioterapia Conformacional/normas , Braquiterapia/efeitos adversos , Medicina Baseada em Evidências , Alemanha , Humanos , Masculino , Estadiamento de Neoplasias , Radioterapia Conformacional/efeitos adversos , Fatores de Risco , Resultado do Tratamento
8.
Radiologe ; 55(10): 859-67, 2015 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-26420600

RESUMO

BACKGROUND: Due to a more effective systemic therapy the survival of patients suffering from malignant tumors has been significantly improved but a longer life span is often associated with a higher incidence of osseous metastases. The majority of these metastases are localized in the spine causing pain, instability and neurological impairments. The interdisciplinary management of spinal metastases previously consisted of stabilization followed by fractionated external body radiation therapy. A reduction in procedural severity and morbidity as well as consideration of self-sufficiency and hospitalization time are important target parameters for these palliative patients. METHOD AND RESULTS: Kyphoplasty combined with intraoperative radiotherapy (Kypho-IORT) is one of several modern treatment options, which involves a minimally invasive procedure with local high-dose transpedicular irradiation of the spine with low-energy (50 kV) X-rays. Immediately following irradiation, stabilization of the spine is carried out using kyphoplasty via the same access route so that a single stage procedure with excellent pain reduction and good local tumor control can be achieved. This article presents clinical data for this procedure and the different fields of indications are critically reviewed and compared to other therapy options. Methodological improvements and options for further individualization of therapy are demonstrated. CONCLUSION: The Kypho-IORT procedure is a safe, feasible and beneficial modern treatment option for instant stabilization and local tumor control in patients with spinal metastases. More than 100 operations have been successfully performed so that the method can be deemed suitable for inclusion in the clinical routine. A phase II dose escalation study has now been completed and submitted for publication and a 2-arm non-inferiority trial (phase III study) for comparison with conventional irradiation is in progress.


Assuntos
Dor nas Costas/prevenção & controle , Cifoplastia/métodos , Recidiva Local de Neoplasia/prevenção & controle , Radioterapia Adjuvante/métodos , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/terapia , Dor nas Costas/etiologia , Terapia Combinada/métodos , Humanos , Cuidados Intraoperatórios/métodos , Neoplasias da Coluna Vertebral/complicações , Resultado do Tratamento
10.
Gastroenterol Res Pract ; 2015: 273489, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25861256

RESUMO

Purpose. The addition of cetuximab to radiochemotherapy (RCT) failed to improve complete response rates in locally advanced rectal cancer (LARC). We report the long-term results in patients treated within two sequential clinical trials. Methods. Patients receiving neoadjuvant RCT using capecitabine and irinotecan (CapIri) within a phase I/II trial or CapIri + cetuximab within a phase II trial were evaluated for analysis of disease-free survival (DFS) and overall survival (OS). KRAS exon 2 mutational status had been analyzed in patients receiving cetuximab. Results. 37 patients from the CapIri trial and 49 patients from the CapIri-cetuximab treatment group were evaluable. Median follow-up time was 75.2 months. The 5-year DFS rate was 82% (CapIri) and 79% (CapIri-cetuximab) (P = 0.62). The median OS was 127.4 months. 5-year OS was 73% for both groups (CapIri and CapIri-cetuximab) (P = 0.61). No significant difference in DFS (P = 0.86) or OS (P = 0.39) was noticed between patients receiving CapIri and those receiving CapIri-cetuximab with KRAS wild-type tumors. Conclusions. As the addition of cetuximab did not improve neither DFS nor OS it should not play a role in the perioperative treatment of patients with LARC, not even of patients with (K)RAS WT tumors.

11.
Phys Med Biol ; 60(6): 2179-94, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25683684

RESUMO

This work discusses a novel strategy for inverse planning in low dose rate brachytherapy. It applies the idea of compressed sensing to the problem of inverse treatment planning and a new solver for this formulation is developed. An inverse planning algorithm was developed incorporating brachytherapy dose calculation methods as recommended by AAPM TG-43. For optimization of the functional a new variant of a matching pursuit type solver is presented. The results are compared with current state-of-the-art inverse treatment planning algorithms by means of real prostate cancer patient data. The novel strategy outperforms the best state-of-the-art methods in speed, while achieving comparable quality. It is able to find solutions with comparable values for the objective function and it achieves these results within a few microseconds, being up to 542 times faster than competing state-of-the-art strategies, allowing real-time treatment planning. The sparse solution of inverse brachytherapy planning achieved with methods from compressed sensing is a new paradigm for optimization in medical physics. Through the sparsity of required needles and seeds identified by this method, the cost of intervention may be reduced.


Assuntos
Algoritmos , Braquiterapia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica
13.
Strahlenther Onkol ; 190(4): 342-51, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24638236

RESUMO

AIM: The purpose of this work is to update the practical guidelines for adjuvant radiotherapy of the regional lymphatics of breast cancer published in 2008 by the breast cancer expert panel of the German Society of Radiation Oncology (DEGRO). METHODS: A comprehensive survey of the literature concerning regional nodal irradiation (RNI) was performed using the following search terms: "breast cancer", "radiotherapy", "regional node irradiation". Recent randomized trials were analyzed for outcome as well as for differences in target definition. Field arrangements in the different studies were reproduced and superimposed on CT slices with individually contoured node areas. Moreover, data from recently published meta-analyses and guidelines of international breast cancer societies, yielding new aspects compared to 2008, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the German interdisciplinary S3 guidelines updated in 2012, this paper addresses indications, targeting, and techniques of radiotherapy of the lymphatic pathways after surgery for breast cancer. RESULTS: International guidelines reveal substantial differences regarding indications for RNI. Patients with 1-3 positive nodes seem to profit from RNI compared to whole breast (WBI) or chest wall irradiation alone, both with regard to locoregional control and disease-free survival. Irradiation of the regional lymphatics including axillary, supraclavicular, and internal mammary nodes provided a small but significant survival benefit in recent randomized trials and one meta-analysis. Lymph node irradiation yields comparable tumor control in comparison to axillary lymph node dissection (ALND), while reducing the rate of lymph edema. Data concerning the impact of 1-2 macroscopically affected sentinel node (SN) or microscopic metastases on prognosis are conflicting. CONCLUSION: Recent data suggest that the current restrictive use of RNI should be scrutinized because the risk-benefit relationship appears to shift towards an improvement of outcome.


Assuntos
Neoplasias da Mama/radioterapia , Carcinoma/radioterapia , Carcinoma/secundário , Linfonodos/efeitos da radiação , Radioterapia (Especialidade)/normas , Radioterapia Conformacional/normas , Relação Dose-Resposta à Radiação , Feminino , Humanos , Metástase Linfática , Dosagem Radioterapêutica
14.
Strahlenther Onkol ; 190(1): 8-16, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24306068

RESUMO

PURPOSE: To complement and update the 2007 practice guidelines of the breast cancer expert panel of the German Society of Radiation Oncology (DEGRO) for radiotherapy (RT) of breast cancer. Owing to its growing clinical relevance, in the current version, a separate paper is dedicated to non-invasive proliferating epithelial neoplasia of the breast. In addition to the more general statements of the German interdisciplinary S3 guidelines, this paper is especially focused on indication and technique of RT in addition to breast conserving surgery. METHODS: The DEGRO expert panel performed a comprehensive survey of the literature comprising recently published data from clinical controlled trials, systematic reviews as well as meta-analyses, referring to the criteria of evidence-based medicine yielding new aspects compared to 2005 and 2007. The literature search encompassed the period 2008 to September 2012 using databases of PubMed and Guidelines International Network (G-I-N). Search terms were "non invasive breast cancer", "ductal carcinoma in situ, "dcis", "borderline breast lesions", "lobular neoplasia", "radiotherapy" and "radiation therapy". In addition to the more general statements of the German interdisciplinary S3 guidelines, this paper is especially focused on indications of RT and decision making of non-invasive neoplasia of the breast after surgery, especially ductal carcinoma in situ. RESULTS: Among different non-invasive neoplasia of the breast only the subgroup of pure ductal carcinoma in situ (DCIS; synonym ductal intraepithelial neoplasia, DIN) is considered for further recurrence risk reduction treatment modalities after complete excision of DCIS, particularly RT following breast conserving surgery (BCS), in order to avoid a mastectomy. About half of recurrences are invasive cancers. Up to 50 % of all recurrences require salvage mastectomy. Randomized clinical trials and a huge number of mostly observational studies have unanimously demonstrated that RT significantly reduces recurrence risks of ipsilateral DCIS as well as invasive breast cancer independent of patient age in all subgroups. The recommended total dose is 50 Gy administered as whole breast irradiation (WBI) in single fractions of 1.8 or 2.0 Gy given on 5 days weekly. Retrospective data indicate a possible beneficial effect of an additional tumor bed boost for younger patients. Prospective clinical trials of different dose-volume concepts (hypofractionation, accelerated partial breast irradiation, boost radiotherapy) are still ongoing. CONCLUSION: Postoperative radiotherapy permits breast conservation for the majority of women by halving local recurrence as well as reducing progression rates into invasive cancer. New data confirmed this effect in all patient subsets-even in low risk subgroups (LoE 1a).


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Radioterapia (Especialidade)/normas , Proteção Radiológica/métodos , Radioterapia Adjuvante/normas , Feminino , Alemanha , Humanos
15.
Zentralbl Chir ; 139 Suppl 2: e72-8, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23115028

RESUMO

The successful treatment of retroperitoneal soft tissue sarcomas requires an experienced team consisting of not only surgeons but also pathologists and radiologists with a high case load in these tumours. The decisive step in the preoperative work-up of these, often late detected, tumours is their reliable grading as well as, if necessary, recognition of the sarcoma subtype as a basis for determining the direction of treatment. Imaging methods provide essential information with regard to the detection of infiltration of neighbouring structures and organs. Magnetic resonance imaging (MRI) is the most suitable method for this purpose. Punch needle biopsy is to be preferred over fine-needle biopsy in all cases for histological confirmation. The surgical standard procedure for the majority of the patients comprises multivisceral resection as principle, with additional colon resection, nephrectomy, and resection of abdominal wall musculature or, respectively, the psoas muscle in order to achieve an R0 resection of the retroperitoneal compartment. If only small margins of clearance are to be expected, a preoperative (neoadjuvant) treatment with radiation and/or chemotherapy even in combination with deep wave hyperthermia for high grade sarcomas should be strongly considered. Adjuvant postoperative radiation therapy often cannot be adequately applied due to the occupation of the former tumour bed by abdominal organs that were displaced by the mass effect, especially the radiation-sensitive small bowel. The optimal treatment strategy for these patients must be discussed in a multidisciplinary tumour board prior to any diagnostic or therapeutic procedure.


Assuntos
Comportamento Cooperativo , Comunicação Interdisciplinar , Equipe de Assistência ao Paciente , Neoplasias Retroperitoneais/cirurgia , Sarcoma/cirurgia , Biópsia por Agulha , Quimiorradioterapia , Terapia Combinada , Humanos , Imageamento por Ressonância Magnética , Gradação de Tumores , Invasividade Neoplásica , Neoplasias Retroperitoneais/diagnóstico , Neoplasias Retroperitoneais/patologia , Sarcoma/diagnóstico , Sarcoma/patologia
16.
Strahlenther Onkol ; 189(11): 938-44, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24068172

RESUMO

BACKGROUND: The use of optical surface positioning to support or replace X-ray-based image-guided radiotherapy (IGRT) may reduce patient exposure to extra dose. In specifically designed phantom tests, we analyzed the potential of a new scanning device preclinically. The system's clinical performance was evaluated in comparison to cone-beam computed tomography (CBCT) in a prospective study. MATERIALS AND METHODS: We first evaluated the scanning performance in terms of accuracy and reproducibility using phantom tests. An institutional review board (IRB)-approved clinical evaluation encompassing 224 fractions in 13 patients treated in three different regions (head and neck, thorax, pelvis) was then performed. Patients were first positioned using CBCT and then scanned with the Catalyst(TM) (C-RAD, Uppsala, Sweden) optical system to define the resulting difference vector. RESULTS: Individual system settings are necessary for different scanning conditions. Reproducibility tests with phantoms showed a mean difference of 0.25 ± 0.21 cm. Accuracy tests showed a mean difference of less than 0.52 ± 0.41 cm. Considering all patients, clinical data showed residual target position differences between Catalyst(TM) (surface-driven) and CBCT (target-driven) systems within 0.07 ± 0.28 cm/- 0.13 ± 0.40 cm/0.15 ± 0.36 cm/0.11 ± 1.57°/- 0.43 ± 1.68/- 0.10 ± 1.67° (lateral/longitudinal/vertical/rotation/roll/pitch). CONCLUSION: Scanning quality depends on the color and shape of the scanned surface. Upon prospective clinical evaluation, excellent agreement between target- and contour driven positioning was observed. Catalyst(TM) may reduce CBCT scan frequency in patients where tumor location is fixed relative to the surface.


Assuntos
Imageamento Tridimensional/instrumentação , Neoplasias/patologia , Neoplasias/radioterapia , Posicionamento do Paciente/instrumentação , Radioterapia Conformacional/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Posicionamento do Paciente/métodos , Imagens de Fantasmas , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
17.
Strahlenther Onkol ; 189(10): 825-33, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24002382

RESUMO

BACKGROUND AND PURPOSE: The aim of the present paper is to update the practical guidelines for postoperative adjuvant radiotherapy of breast cancer published in 2007 by the breast cancer expert panel of the German Society for Radiooncology (Deutsche Gesellschaft für Radioonkologie, DEGRO). The present recommendations are based on a revision of the German interdisciplinary S-3 guidelines published in July 2012. METHODS: A comprehensive survey of the literature concerning radiotherapy following breast conserving therapy (BCT) was performed using the search terms "breast cancer", "radiotherapy", and "breast conserving therapy". Data from lately published meta-analyses, recent randomized trials, and guidelines of international breast cancer societies, yielding new aspects compared to 2007, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the DKG (Deutsche Krebsgesellschaft), this paper addresses indications, target definition, dosage, and technique of radiotherapy of the breast after conservative surgery for invasive breast cancer. RESULTS: Among numerous reports on the effect of radiotherapy during BCT published since the last recommendations, the recent EBCTCG report builds the largest meta-analysis so far available. In a 15 year follow-up on 10,801 patients, whole breast irradiation (WBI) halves the average annual rate of disease recurrence (RR 0.52, 0.48-0.56) and reduces the annual breast cancer death rate by about one sixth (RR 0.82, 0.75-0.90), with a similar proportional, but different absolute benefit in prognostic subgroups (EBCTCG 2011). Furthermore, there is growing evidence that risk-adapted dose augmentation strategies to the tumor bed as well as the implementation of high precision RT techniques (e.g., intraoperative radiotherapy) contribute substantially to a further reduction of local relapse rates. A main focus of ongoing research lies in partial breast irradiation strategies as well as WBI hypofractionation schedules. The potential of both in replacing normofractionated WBI has not yet been finally clarified. CONCLUSION: After breast conserving surgery, no subgroup even in low risk patients has yet been identified for whom radiotherapy can be safely omitted without compromising local control and, hence, cancer-specific survival. In most patients, this translates into an overall survival benefit.


Assuntos
Neoplasias da Mama/terapia , Mastectomia Segmentar/normas , Oncologia/normas , Radioterapia Conformacional/normas , Terapia Combinada/normas , Feminino , Alemanha , Humanos , Invasividade Neoplásica , Radioterapia Adjuvante/normas
19.
Orthopade ; 42(9): 772-9, 2013 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-23989594

RESUMO

The Kypho-IORT procedure is a recently developed surgical technique to combine intraoperative radiotherapy with cement augmentation of the vertebra for spinal metastases. The technical feasibility and the operation principle of this new method have been described. In the following article the refinement of the standard operation procedure and the technical development of the method are described. Not only the procedural improvements but also the learning curves of the inaugurators are pointed out. Moreover, the article presents the measures which were necessary to educate trainees during surgical master classes in this new method and to transfer the method. The learning success was quantified by recording the accuracy reached by the trainees in the key procedure during hands-on cadaver exercises. Improvements of the standard operation procedure could be successfully transferred in a second master class. The method of Kypho-IORT and the demonstrated way of postgraduate education is feasible to instruct trainees. The Kypho-IORT procedure can be learnt and performed safely by running through the surgical master class.


Assuntos
Educação Médica Continuada/métodos , Cifoplastia/educação , Laminectomia/educação , Competência Profissional , Radioterapia Conformacional/métodos , Fusão Vertebral/educação , Neoplasias da Coluna Vertebral/terapia , Cadáver , Terapia Combinada/métodos , Avaliação Educacional , Alemanha , Humanos , Cifoplastia/métodos , Laminectomia/métodos , Fusão Vertebral/métodos , Resultado do Tratamento
20.
Orthopade ; 42(9): 765-71, 2013 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-23887850

RESUMO

BACKGROUND: Operative and radiotherapeutic procedures are available for the treatment of symptomatic vertebral metastases. The method for treatment of vertebral metastases presented in this article involves a combination of intraoperative radiotherapy (IORT) and kyphoplasty. METHODS AND RESULTS: Kyphoplasty-IORT allows treatment of symptomatic vertebral metastases between vertebrae T3 and L5. With the patient under intubation narcosis an extrapedicular or bipedicular access to the vertebra is selected as for conventional kyphoplasty. This is followed by insertion of special sheaths of the radiation applicator and radiation therapy is intraoperatively administered via a radiation generator (Intrabeam®, Carl Zeiss Surgical, Oberkochen, Germany). The radiation dose is 8 Gy at a depth of 5-10 mm depending on the study protocol (50 kV X-radiation). Following radiation a conventional kyphoplasty procedure (Medtronic, USA) is carried out and the vertebra stabilized with cement. CONCLUSIONS: The procedure presented demonstrates a new approach to treatment of vertebral metastases and represents a valuable alternative to previously established methods.


Assuntos
Cifoplastia/métodos , Laminectomia/métodos , Radioterapia Conformacional/métodos , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/terapia , Algoritmos , Terapia Combinada/métodos , Humanos , Neoplasias da Coluna Vertebral/diagnóstico , Resultado do Tratamento
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