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1.
BMC Cancer ; 24(1): 513, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654241

RESUMO

BACKGROUND: [18F]FDG-PET/CT is used for staging and treatment planning in patients with locally advanced cervical cancer (LACC). We studied if a PET-based prediction model could provide additional risk stratification beyond International Federation of Gynaecology and Obstetrics (FIGO) staging in our population with LACC to aid treatment decision making. METHODS: In total, 183 patients with LACC treated with chemoradiation between 2013 and 2018 were included. Patients were treated according to FIGO 2009 and retrospectively reclassified according to FIGO 2018 staging system. After validation of an existing PET-based prediction model, the predicted recurrent free survival (RFS), disease specific survival (DSS) and overall survival (OS) at 1, 3, and 5 years, based on metabolic tumor volume (MTV), maximum standardized uptake value (SUVmax) and highest level of [18F]FDG-positive node was calculated. Then the observed survival was compared to the predicted survival. An area under the curve (AUC) close to or higher than 0.7 was considered adequate for accurate prediction. The Youden (J) index defined survival chance cutoff values for low and high risk groups. RESULTS: All AUC values for the comparison between predicted and observed outcomes were > 0.7 except for 5-year RFS and for 5-year OS which were close to 0.7 (0.684 and 0.650 respectively). Cutoff values for low and high risk survival chance were 0.44 for the 3-year RFS and 0.47 for the 5-year OS. The FIGO 2009 system could not differentiate between the risk profiles. After reclassification according to FIGO 2018, all patients with stage IIIC2 and IVB fell in the high risk and almost all patients with stages IB2-IIIB and IVA in the low risk group. In patients with stage IIIC1 disease the FIGO stage cannot discriminate between the risk profiles. CONCLUSIONS: Low and high risk patients with LACC can be identified with the PET-based prediction model. In particular patients with stage IIIC1 need additional risk stratification besides the FIGO 2018 staging. The Kidd model could be a useful tool to aid treatment decision making in these patients. Our results also support the choice of [18F]FDG-PET/CT imaging in patients with LACC.


Assuntos
Fluordesoxiglucose F18 , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Idoso , Medição de Risco/métodos , Quimiorradioterapia , Compostos Radiofarmacêuticos , Idoso de 80 Anos ou mais , Prognóstico
2.
Adv Drug Deliv Rev ; 163-164: 84-97, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31982475

RESUMO

Mild hyperthermia, local heating of the tumour up to temperatures <43 °C, has been clinically applied for almost four decades and has been proven to substantially enhance the effectiveness of both radiotherapy and chemotherapy in treatment of primary and recurrent tumours. Clinical results and mechanisms of action are discussed in this review, including the molecular and biological rationale of hyperthermia as radio- and chemosensitizer as established in in vitro and in vivo experiments. Proven mechanisms include inhibition of different DNA repair processes, (in)direct reduction of the hypoxic tumour cell fraction, enhanced drug uptake, increased perfusion and oxygen levels. All mechanisms show different dose effect relationships and different optimal scheduling with radiotherapy and chemotherapy. Therefore, obtaining the ideal multi-modality treatment still requires elucidation of more detailed data on dose, sequence, duration, and possible synergisms between modalities. A multidisciplinary approach with different modalities including hyperthermia might further increase anti-tumour effects and diminish normal tissue damage.


Assuntos
Antineoplásicos/urina , Hipertermia Induzida/métodos , Neoplasias/terapia , Radioterapia/métodos , Animais , Antineoplásicos/administração & dosagem , Terapia Combinada , Dano ao DNA/fisiologia , Humanos , Hipertermia/fisiopatologia , Fatores de Tempo , Microambiente Tumoral/fisiologia
3.
Radiat Oncol ; 14(1): 126, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300000

RESUMO

BACKGROUND: Online magnetic resonance imaging (MRI)-guided radiotherapy of cervical cancer has the potential to further reduce dose to organs at risk (OAR) as compared to a library of plans (LOP) approach. This study presents a dosimetric comparison of an MRI-guided strategy with a LOP strategy taking intrafraction anatomical changes into account. METHODS: The 14 patients included in this study were treated with chemo radiation at our institute and received weekly MRIs after informed consent. The MRI-guided strategy consisted of treatment plans created on the weekly sagittal MRI with 3 mm and 5 mm planning target volume (PTV) margin for clinical target volume (CTV) cervix-uterus (MRI_3mm and MRI_5mm). The plans for the LOP strategy were based on interpolations of CTV cervix-uterus on pretreatment full and empty bladder scans. Dose volume histogram (DVH) parameters were compared for targets and OARs as delineated on the weekly transversal MRI, which was acquired on average 10 min after the sagittal MRI. RESULTS: For the MRI_5mm strategy D98% of the high-risk CTV was at least 95% for all weekly MRIs of all patients, while for the LOP and MRI_3mm strategy this requirement was not satisfied for at least one weekly MRI for 1 and 3 patients, respectively. The average reduction of the volume of the reference dose (95% of the prescribed dose) as compared to the LOP strategy was 464 cm3 for the MRI_3mm strategy, and 422 cm3 for the MRI_5mm strategy. The bowel bag constraint V40Gy < 350 cm3 was violated for 13 patients for the LOP strategy and for 5 patients for both MRI_3mm and MRI_5mm strategy. CONCLUSIONS: With online MRI-guided radiotherapy of cervical cancer considerable sparing of OARs can be achieved. If a new treatment plan can be generated and delivered within 10 min, an online MRI-guided strategy with a 5 mm PTV margin for CTV cervix-uterus is sufficient to account for intrafraction anatomical changes. TRIAL REGISTRATION: NL44492.018.13.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Variação Anatômica , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Fracionamento da Dose de Radiação , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Prognóstico , Radiometria/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia
4.
Int J Hyperthermia ; 35(1): 330-339, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30300028

RESUMO

INTRODUCTION: On-line adaptive hyperthermia treatment planning can be useful to suppress treatment limiting hot spots and improve tumor temperatures during locoregional hyperthermia. This requires adequate prediction of changes in heating patterns after phase-amplitude steering. We investigated the predictive value of simulated SAR and temperature for changes in measured temperature after phase-amplitude steering during locoregional hyperthermia. METHODS: All treatment sessions of 75 patients with pelvic malignancies treated between September 2013 and March 2018 were evaluated. Phase-amplitude adaptations during the 60 min steady-state period were analyzed. Treatment planning was performed using Plan2Heat, based on CT scans with (thermometry) catheters in the vagina, rectum, and bladder in situ. The predicted SAR and temperature along the thermometry tracks were extracted from the simulated distributions. Correlations between changes in average measured temperature and the simulated SAR and temperature were evaluated for single phase-amplitude steering events, unaccompanied by other (steering) actions. RESULTS: A total of 67 phase-amplitude steering events were suitable for analysis. Simulated changes in both SAR and temperature correlated with the measured temperature changes. For the vagina, R2 = 0.44 and R2 = 0.55 for SAR and temperature, respectively. For the rectum, these values were 0.53 for SAR and 0.66 for temperature. Correlations for the bladder were weaker: R2 = 0.15 and R2 = 0.14 for SAR and temperature, respectively. This can be explained by convection in the bladder fluid, unaccounted for by present treatment planning. CONCLUSION: Treatment planning can predict changes in an average temperature after phase-amplitude steering. This allows on-line support with phase-amplitude steering to optimize hyperthermia treatments.


Assuntos
Hipertermia Induzida/efeitos adversos , Terapia Assistida por Computador/métodos , Humanos , Valor Preditivo dos Testes , Temperatura
5.
Int J Hyperthermia ; 34(7): 901-909, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29749270

RESUMO

PURPOSE: Thermoradiotherapy is an effective treatment for locally advanced cervical cancer. However, the optimal time interval between radiotherapy and hyperthermia, resulting in the highest therapeutic gain, remains unclear. This study aims to evaluate the effect of time interval on the therapeutic gain using biological treatment planning. METHODS: Radiotherapy and hyperthermia treatment plans were created for 15 cervical cancer patients. Biological modeling was used to calculate the equivalent radiation dose, that is, the radiation dose that results in the same biological effect as the thermoradiotherapy treatment, for different time intervals ranging from 0-4 h. Subsequently, the thermal enhancement ratio (TER, i.e. the ratio of the dose for the thermoradiotherapy and the radiotherapy-only plan) was calculated for the gross tumor volume (GTV) and the organs at risk (OARs: bladder, rectum, bowel), for each time interval. Finally, the therapeutic gain factor (TGF, i.e. TERGTV/TEROAR) was calculated for each OAR. RESULTS: The median TERGTV ranged from 1.05 to 1.16 for 4 h and 0 h time interval, respectively. Similarly, for bladder, rectum and bowel, TEROARs ranged from 1-1.03, 1-1.04 and 1-1.03, respectively. Radiosensitization in the OARs was much less than in the GTV, because temperatures were lower, fractionation sensitivity was higher (lower α/ß) and direct cytotoxicity was assumed negligible in normal tissue. TGFs for the three OARs were similar, and were highest (around 1.12) at 0 h time interval. CONCLUSION: This planning study indicates that the largest therapeutic gain for thermoradiotherapy in cervical cancer patients can be obtained when hyperthermia is delivered immediately before or after radiotherapy.


Assuntos
Dosagem Radioterapêutica/normas , Neoplasias do Colo do Útero/radioterapia , Fracionamento da Dose de Radiação , Feminino , Humanos , Hipertermia Induzida/métodos , Doses de Radiação
6.
Radiat Oncol ; 13(1): 96, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29769103

RESUMO

BACKGROUND: Prediction of radiobiological response is a major challenge in radiotherapy. Of several radiobiological models, the linear-quadratic (LQ) model has been best validated by experimental and clinical data. Clinically, the LQ model is mainly used to estimate equivalent radiotherapy schedules (e.g. calculate the equivalent dose in 2 Gy fractions, EQD2), but increasingly also to predict tumour control probability (TCP) and normal tissue complication probability (NTCP) using logistic models. The selection of accurate LQ parameters α, ß and α/ß is pivotal for a reliable estimate of radiation response. The aim of this review is to provide an overview of published values for the LQ parameters of human tumours as a guideline for radiation oncologists and radiation researchers to select appropriate radiobiological parameter values for LQ modelling in clinical radiotherapy. METHODS AND MATERIALS: We performed a systematic literature search and found sixty-four clinical studies reporting α, ß and α/ß for tumours. Tumour site, histology, stage, number of patients, type of LQ model, radiation type, TCP model, clinical endpoint and radiobiological parameter estimates were extracted. Next, we stratified by tumour site and by tumour histology. Study heterogeneity was expressed by the I2 statistic, i.e. the percentage of variance in reported values not explained by chance. RESULTS: A large heterogeneity in LQ parameters was found within and between studies (I2 > 75%). For the same tumour site, differences in histology partially explain differences in the LQ parameters: epithelial tumours have higher α/ß values than adenocarcinomas. For tumour sites with different histologies, such as in oesophageal cancer, the α/ß estimates correlate well with histology. However, many other factors contribute to the study heterogeneity of LQ parameters, e.g. tumour stage, type of LQ model, TCP model and clinical endpoint (i.e. survival, tumour control and biochemical control). CONCLUSIONS: The value of LQ parameters for tumours as published in clinical radiotherapy studies depends on many clinical and methodological factors. Therefore, for clinical use of the LQ model, LQ parameters for tumour should be selected carefully, based on tumour site, histology and the applied LQ model. To account for uncertainties in LQ parameter estimates, exploring a range of values is recommended.


Assuntos
Fracionamento da Dose de Radiação , Modelos Estatísticos , Neoplasias/classificação , Neoplasias/radioterapia , Humanos , Modelos Lineares
7.
Int J Hyperthermia ; 34(7): 1082-1091, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29145750

RESUMO

BACKGROUND: The effectiveness of hyperthermia is strongly dependent on the achieved tumour temperatures. Phased-array systems allow flexible power steering to realise good tumour heating while avoiding excessive heating in normal tissue, but the limited quantitative accuracy of pre-treatment planning complicates realising optimal tumour heating. On-line hyperthermia treatment planning could help to improve the heating quality. This paper demonstrates the feasibility of using on-line temperature-based treatment planning to improve the heating quality during hyperthermia in three patients. METHODS: Hyperthermia treatment planning was performed using the Plan2Heat software package combined with a dedicated graphical user interface for on-line application. Electric fields were pre-calculated to allow instant update and visualisation of the predicted temperature distribution for user-selected phase-amplitude settings during treatment. On-line treatment planning using manual variation of system settings for the AMC-8 hyperthermia system was applied in one patient with a deep-seated pelvic melanoma metastasis and two cervical cancer patients. For a clinically relevant improvement the increase in average target temperature should be at least 0.2 °C. RESULTS: With the assistance of on-line treatment planning a substantial improvement in tumour temperatures was realised for all three patients. In the melanoma patient, the average measured target temperature increased from 38.30 °C to 39.15 °C (i.e. +0.85 °C). In the cervical cancer patients, the average measured target temperature increased from 41.30 °C to 42.05 °C (i.e. +0.75 °C) and from 41.70 °C to 42.80 °C (i.e. +1.1 °C), respectively. CONCLUSION: On-line temperature-based treatment planning is clinically feasible to improve tumour temperatures. A next, worthwhile step is automatic optimisation for a larger number of patients.


Assuntos
Hipertermia Induzida/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Int J Hyperthermia ; 34(1): 30-38, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28540813

RESUMO

PURPOSE: Biological modelling of thermoradiotherapy may further improve patient selection and treatment plan optimisation, but requires a model that describes the biological effect as a function of variables that affect treatment outcome (e.g. temperature, radiation dose). This study aimed to establish such a model and its parameters. Additionally, a clinical example was presented to illustrate the application. METHODS: Cell survival assays were performed at various combinations of radiation dose (0-8 Gy), temperature (37-42 °C), time interval (0-4 h) and treatment sequence (radiotherapy before/after hyperthermia) for two cervical cancer cell lines (SiHa and HeLa). An extended linear-quadratic model was fitted to the data using maximum likelihood estimation. As an example application, a thermoradiotherapy plan (23 × 2 Gy + weekly hyperthermia) was compared with a radiotherapy-only plan (23 × 2 Gy) for a cervical cancer patient. The equivalent uniform radiation dose (EUD) in the tumour, including confidence intervals, was estimated using the SiHa parameters. Additionally, the difference in tumour control probability (TCP) was estimated. RESULTS: Our model described the dependency of cell survival on dose, temperature and time interval well for both SiHa and HeLa data (R2=0.90 and R2=0.91, respectively), making it suitable for biological modelling. In the patient example, the thermoradiotherapy plan showed an increase in EUD of 9.8 Gy that was robust (95% CI: 7.7-14.3 Gy) against propagation of the uncertainty in radiobiological parameters. This corresponded to a 20% (95% CI: 15-29%) increase in TCP. CONCLUSIONS: This study presents a model that describes the cell survival as a function of radiation dose, temperature and time interval, which is essential for biological modelling of thermoradiotherapy treatments.


Assuntos
Radioterapia/métodos , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Humanos , Dosagem Radioterapêutica , Temperatura , Fatores de Tempo
9.
Gynecol Oncol ; 147(3): 684-689, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29074259

RESUMO

OBJECTIVE: To evaluate the frequency of and risk factors for severe late bowel toxicity after curative radiotherapy in women treated for locally advanced cervical cancer. METHODS: Included were 515 women treated for locally advanced cervical cancer with primary radiotherapy with curative intent from 1992 to 2013. Bowel toxicity was graded according to the Common Terminology Criteria for Adverse Events. Associations between risk factors and severe late bowel toxicity were assessed using Cox proportional hazards regression models. RESULTS: Median follow-up was 78months. Fifty-nine patients developed severe late bowel toxicity. The actuarial 3-year and 5-year severe late bowel toxicity rates were both 13%. In the multivariable analysis, factors significantly associated with severe late bowel toxicity were: smoking (HR 2.59 [1.48-4.55]), severe acute bowel toxicity (HR 2.46 [1.24-4.49]), previous major abdominal surgery (HR 2.35 [1.20-4.60]), hypertension (HR 2.33 [1.23-4.40]), parametrial boost (HR 2.18 [1.10-4.33]), low socioeconomic status (HR 2.05 [1.17-3.59]) and low BMI (HR 0.93 [0.88-0.99]). First symptoms of severe late bowel toxicity were reported after a median follow-up of 9months, but occurred up to 10years after end of treatment. Only one third of the patients with severe late bowel toxicity were referred to a gastroenterologist. CONCLUSIONS: Severe late bowel toxicity is a frequent complication of definitive radiotherapy for cervical cancer. Several independent risk factors were found which warrant further research. A standardized and structured approach in the early diagnostics and management of bowel toxicity is needed.


Assuntos
Lesões por Radiação/economia , Lesões por Radiação/etiologia , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Classe Social , Adulto Jovem
10.
Int J Hyperthermia ; 33(2): 160-169, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27744728

RESUMO

PURPOSE: Currently, clinical decisions regarding thermoradiotherapy treatments are based on clinical experience. Quantification of the radiosensitising effect of hyperthermia allows comparison of different treatment strategies, and can support clinical decision-making regarding the optimal treatment. The software presented here enables biological evaluation of thermoradiotherapy plans through calculation of equivalent 3D dose distributions. METHODS: Our in-house developed software (X-Term) uses an extended version of the linear-quadratic model to calculate equivalent radiation dose, i.e. the radiation dose yielding the same effect as the thermoradiotherapy treatment. Separate sets of model parameters can be assigned to each delineated structure, allowing tissue specific modelling of hyperthermic radiosensitisation. After calculation, the equivalent radiation dose can be evaluated according to conventional radiotherapy planning criteria. The procedure is illustrated using two realistic examples. First, for a previously irradiated patient, normal tissue dose for a radiotherapy and thermoradiotherapy plan (with equal predicted tumour control) is compared. Second, tumour control probability (TCP) is assessed for two (otherwise identical) thermoradiotherapy schedules with different time intervals between radiotherapy and hyperthermia. RESULTS: The examples demonstrate that our software can be used for individualised treatment decisions (first example) and treatment optimisation (second example) in thermoradiotherapy. In the first example, clinically acceptable doses to the bowel were exceeded for the conventional plan, and a substantial reduction of this excess was predicted for the thermoradiotherapy plan. In the second example, the thermoradiotherapy schedule with long time interval was shown to result in a substantially lower TCP. CONCLUSIONS: Using biological modelling, our software can facilitate the evaluation of thermoradiotherapy plans and support individualised treatment decisions.

11.
Radiat Oncol ; 11: 14, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26831185

RESUMO

BACKGROUND: Locoregional hyperthermia combined with radiotherapy significantly improves locoregional control and overall survival for cervical tumors compared to radiotherapy alone. In this study biological modelling is applied to quantify the effect of radiosensitization for three cervical cancer patients to evaluate the improvement in equivalent dose for the combination treatment with radiotherapy and hyperthermia. METHODS: The Linear-Quadratic (LQ) model extended with temperature-dependent LQ-parameters α and ß was used to model radiosensitization by hyperthermia and to calculate the conventional radiation dose that is equivalent in biological effect to the combined radiotherapy and hyperthermia treatment. External beam radiotherapy planning was performed based on a prescription dose of 46Gy in 23 fractions of 2Gy. Hyperthermia treatment using the AMC-4 system was simulated based on the actual optimized system settings used during treatment. RESULTS: The simulated hyperthermia treatments for the 3 patients yielded a T50 of 40.1 °C, 40.5 °C, 41.1 °C and a T90 of 39.2 °C, 39.7 °C, 40.4 °C, respectively. The combined radiotherapy and hyperthermia treatment resulted in a D95 of 52.5Gy, 55.5Gy, 56.9Gy in the GTV, a dose escalation of 7.3-11.9Gy compared to radiotherapy alone (D95 = 45.0-45.5Gy). CONCLUSIONS: This study applied biological modelling to evaluate radiosensitization by hyperthermia as a radiation-dose escalation for cervical cancer patients. This model is very useful to compare the effectiveness of different treatment schedules for combined radiotherapy and hyperthermia treatments and to guide the design of clinical studies on dose escalation using hyperthermia in a multi-modality setting.


Assuntos
Relação Dose-Resposta à Radiação , Hipertermia Induzida/métodos , Radioterapia/métodos , Neoplasias do Colo do Útero/radioterapia , Ensaios Clínicos como Assunto , Feminino , Humanos , Modelos Lineares , Radiossensibilizantes/química , Interpretação de Imagem Radiográfica Assistida por Computador , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Temperatura , Tomografia Computadorizada por Raios X
12.
Phys Med Biol ; 61(4): 1596-607, 2016 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-26836010

RESUMO

The in vivo electric conductivity (σ) values of tissue are essential for accurate electromagnetic simulations and specific absorption rate (SAR) assessment for applications such as thermal dose computations in hyperthermia. Currently used σ-values are mostly based on ex vivo measurements. In this study the conductivity of human muscle, bladder content and cervical tumors is acquired non-invasively in vivo using MRI. The conductivity of 20 cervical cancer patients was measured with the MR-based electric properties tomography method on a standard 3T MRI system. The average in vivo σ-value of muscle is 14% higher than currently used in human simulation models. The σ-value of bladder content is an order of magnitude higher than the value for bladder wall tissue that is used for the complete bladder in many models. Our findings are confirmed by various in vivo animal studies from the literature. In cervical tumors, the observed average conductivity was 13% higher than the literature value reported for cervical tissue. Considerable deviations were found for the electrical conductivity observed in this study and the commonly used values for SAR assessment, emphasizing the importance of acquiring in vivo conductivity for more accurate SAR assessment in various applications.


Assuntos
Condutividade Elétrica , Hipertermia Induzida/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/terapia , Feminino , Humanos , Hipertermia Induzida/normas
13.
Ann Oncol ; 25(4): 896-901, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24615411

RESUMO

BACKGROUND: Cancer patients need to trust their oncologist to embark in the process of oncologic treatment. Yet, it is unclear how oncologist communication contributes to such trust. The aim of this study was to investigate the effect of three elements of oncologists' communication on cancer patients' trust: conferring competence, honesty, and caring. METHODS: Eight videotaped consultations, 'vignettes', were created, reflecting an encounter between an oncologist and a patient with colorectal cancer. All vignettes were identical, except for small variations in the oncologist's verbal communication. Cancer patients (n = 345) were randomly assigned to viewing two vignettes, asked to identify with the patient and afterwards to rate their trust in the observed oncologist. The effects of competence, honesty, and caring on trust were established with multilevel analysis. RESULTS: Oncologist's enhanced expression of competence (ß = 0.17, 95% CI 0.08, 0.27; P < 0.001), honesty (ß = 0.30, 95% CI 0.20, 0.40; P < 0.001), as well as caring (ß = 0.36, 95% CI 0.26, 0.46; P < 0.001) resulted in significantly increased trust. Communication of honesty and caring also increased patients' expectation of operation success and reported willingness to recommend the oncologist. CONCLUSION(S): As hypothesized, oncologists can influence their patients' trust by enhanced conveyance of their level of competence, honesty, and caring. Caring behavior has the strongest impact on trust. These findings can be translated directly into daily clinical practice as well as in communication skills training.


Assuntos
Neoplasias/psicologia , Pacientes/psicologia , Relações Médico-Paciente , Confiança/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Comunicação , Feminino , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Neoplasias/patologia , Médicos/psicologia , Gravação de Videoteipe
14.
Med Phys ; 41(3): 031707, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24593711

RESUMO

PURPOSE: The aim of this study is to develop and validate a generic method for automatic bladder segmentation on cone beam computed tomography (CBCT), independent of gender and treatment position (prone or supine), using only pretreatment imaging data. METHODS: Data of 20 patients, treated for tumors in the pelvic region with the entire bladder visible on CT and CBCT, were divided into four equally sized groups based on gender and treatment position. The full and empty bladder contour, that can be acquired with pretreatment CT imaging, were used to generate a patient-specific bladder shape model. This model was used to guide the segmentation process on CBCT. To obtain the bladder segmentation, the reference bladder contour was deformed iteratively by maximizing the cross-correlation between directional grey value gradients over the reference and CBCT bladder edge. To overcome incorrect segmentations caused by CBCT image artifacts, automatic adaptations were implemented. Moreover, locally incorrect segmentations could be adapted manually. After each adapted segmentation, the bladder shape model was expanded and new shape patterns were calculated for following segmentations. All available CBCTs were used to validate the segmentation algorithm. The bladder segmentations were validated by comparison with the manual delineations and the segmentation performance was quantified using the Dice similarity coefficient (DSC), surface distance error (SDE) and SD of contour-to-contour distances. Also, bladder volumes obtained by manual delineations and segmentations were compared using a Bland-Altman error analysis. RESULTS: The mean DSC, mean SDE, and mean SD of contour-to-contour distances between segmentations and manual delineations were 0.87, 0.27 cm and 0.22 cm (female, prone), 0.85, 0.28 cm and 0.22 cm (female, supine), 0.89, 0.21 cm and 0.17 cm (male, supine) and 0.88, 0.23 cm and 0.17 cm (male, prone), respectively. Manual local adaptations improved the segmentation results significantly (p < 0.01) based on DSC (6.72%) and SD of contour-to-contour distances (0.08 cm) and decreased the 95% confidence intervals of the bladder volume differences. Moreover, expanding the shape model improved the segmentation results significantly (p < 0.01) based on DSC and SD of contour-to-contour distances. CONCLUSIONS: This patient-specific shape model based automatic bladder segmentation method on CBCT is accurate and generic. Our segmentation method only needs two pretreatment imaging data sets as prior knowledge, is independent of patient gender and patient treatment position and has the possibility to manually adapt the segmentation locally.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias Pélvicas/radioterapia , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/efeitos da radiação , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Modelos Estatísticos , Posicionamento do Paciente , Imagens de Fantasmas , Decúbito Ventral , Radioterapia Guiada por Imagem/métodos , Reprodutibilidade dos Testes , Decúbito Dorsal
15.
Strahlenther Onkol ; 188(9): 802-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22526228

RESUMO

BACKGROUND: This study aimed to develop and validate a survival scoring system for patients with metastatic spinal cord compression (MSCC) from prostate cancer. PATIENTS AND METHODS: Of 436 patients, 218 patients were assigned to the test group and 218 patients to the validation group. Eight potential prognostic factors (age, performance status, number of involved vertebrae, ambulatory status, other bone metastases, visceral metastases, interval from cancer diagnosis to radiotherapy of MSCC, time developing motor deficits) plus the fractionation regimen were retrospectively investigated for associations with survival. Factors significant in the multivariate analysis were included in the survival score. The score for each significant prognostic factor was determined by dividing the 6-month survival rate (%) by 10. The total score represented the sum of the scores for each factor. The prognostic groups of the test group were compared to the validation group. RESULTS: In the multivariate analysis of the test group, performance status, ambulatory status, other bone metastases, visceral metastases, and interval from cancer diagnosis to radiotherapy were significantly associated with survival. Total scores including these factors were 20, 21, 22, 24, 26, 28, 29, 30, 31, 32, 33, 35, 37, or 39 points. In the test group, the 6-month survival rates were 6.5% for 20-24 points, 44.6% for 26-33 points, and 95.8% for 35-39 points (p < 0.0001). In the validation group, the 6-month survival rates were 7.4%, 45.4%, and 94.7%, respectively (p < 0.0001). CONCLUSIONS: Because the survival rates of the validation group were almost identical to the test group, this score can be considered valid and reproducible.


Assuntos
Modelos de Riscos Proporcionais , Neoplasias da Próstata/complicações , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/mortalidade , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/secundário , Análise de Sobrevida , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Medição de Risco/métodos , Fatores de Risco , Compressão da Medula Espinal/prevenção & controle , Neoplasias da Coluna Vertebral/mortalidade , Neoplasias da Coluna Vertebral/prevenção & controle , Taxa de Sobrevida , Resultado do Tratamento
16.
Strahlenther Onkol ; 188(4): 340-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22354333

RESUMO

BACKGROUND: This study was performed to identify new significant prognostic factors in breast cancer patients irradiated for metastatic spinal cord compression (MSCC). PATIENTS AND METHODS: The data of 504 patients with breast cancer patients with MSCC were retrospectively analyzed with respect to posttreatment motor function, local control of MSCC, and survival. The investigated potential prognostic factors included age, Eastern Cooperative Oncology Group (ECOG) performance score, number of involved vertebrae, other bone metastases, visceral metastases, pretreatment ambulatory status, interval from cancer diagnosis to radiotherapy of MSCC, time developing motor deficits before radiotherapy, and the radiation schedule. RESULTS: On multivariate analysis, better functional outcome was associated with ambulatory status prior to RT (estimate - 1.29, p < 0.001), no visceral metastases (estimate - 0.52, p = 0.020), and slower development of motor deficits (estimate + 2.47, p < 0.001). Improved local control was significantly associated with no other bone metastases (risk ratio (RR) 4.33, 95% confidence interval (CI) 1.36-14.02, p = 0.013) and no visceral metastases (RR 3.02, 95% CI 1.42-6.40, p = 0.005). Improved survival was significantly associated with involvement of only 1-2 vertebrae (RR 1.27, 95% CI 1.01-1.60, p = 0.044), ambulatory status before radiotherapy (RR 1.75, 95% CI 1.23-2.50, p = 0.002), no other bone metastases (RR 1.93, 95% CI 1.18-3.13, p = 0.009), no visceral metastases (RR 7.60, 95% CI 5.39-10.84, p < 0.001), and time developing motor deficits before radiotherapy (RR 1.55, 95% CI 1.30-1.86, p < 0.001). CONCLUSION: Several new independent prognostic factors were identified for treatment outcomes. These prognostic factors should be considered in future trials and may be used to develop prognostic scores for breast cancer patients with MSCC.


Assuntos
Neoplasias da Mama/radioterapia , Vértebras Lombares , Compressão da Medula Espinal/radioterapia , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/secundário , Vértebras Torácicas , Atividades Cotidianas/classificação , Idoso , Antieméticos/administração & dosagem , Estudos de Coortes , Dexametasona/administração & dosagem , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Vértebras Lombares/efeitos da radiação , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Limitação da Mobilidade , Análise Multivariada , Estadiamento de Neoplasias , Exame Neurológico/efeitos da radiação , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Compressão da Medula Espinal/mortalidade , Compressão da Medula Espinal/patologia , Neoplasias da Coluna Vertebral/mortalidade , Neoplasias da Coluna Vertebral/patologia , Análise de Sobrevida , Vértebras Torácicas/efeitos da radiação , Tomografia Computadorizada por Raios X
17.
Strahlenther Onkol ; 188(6): 472-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22361746

RESUMO

BACKGROUND: Patients with metastatic spinal cord compression (MSCC) from non-small cell lung cancer (NSCLC) have an unfavorable prognosis compared to most other MSCC patients. This study was performed to identify prognostic factors for functional outcome and survival in these patients after radiotherapy (RT) alone. PATIENTS AND METHODS: Data of 356 patients irradiated for MSCC from NSCLC were retrospectively analyzed. Ten potential prognostic factors were investigated including age, gender, Eastern cooperative Oncology Group performance score (ECOG-PS), number of involved vertebrae, pre-RT ambulatory status, other bone metastases, visceral metastases, interval from cancer diagnosis to RT of MSCC, time developing motor deficits before RT, and the radiation schedule. RESULTS: On multivariate analysis, better functional outcome was associated with pre-RT ambulatory status (estimate: - 0.84, p = 0.022), no visceral metastases (estimate: - 1.15, p < 0.001), interval from cancer diagnosis to RT of > 15 months (estimate: + 0.48, p = 0.019), and slower (> 7 days) development of motor deficits (estimate: + 1.56, p < 0.001). On multivariate analysis, improved survival was significantly associated with female gender (risk ratio (RR) 1.32, p = 0.043), ECOG-PS 1-2 (RR 1.45, p = 0.034), pre-RT ambulatory status (RR 0.58, p < 0.001), no other bone metastases (RR 1.38, p = 0.010), no visceral metastases (RR 2.87, p < 0.001), interval from cancer diagnosis to RT of > 15 months (RR 0.84, p = 0.035), and slower (> 7 days) development of motor deficits (RR 0.78, p < 0.001). CONCLUSION: This study identified additional independent prognostic factors for outcomes after radiotherapy of MSCC from NSCLC. These prognostic factors can be used for stratification in future trials and can help develop prognostic scores for MSCC from NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/secundário , Neoplasias Pulmonares/radioterapia , Compressão da Medula Espinal/radioterapia , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/secundário , Fatores Etários , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Avaliação da Deficiência , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Exame Neurológico , Prognóstico , Estudos Retrospectivos , Fatores Sexuais , Medula Espinal/patologia , Compressão da Medula Espinal/diagnóstico , Compressão da Medula Espinal/mortalidade , Neoplasias da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/mortalidade , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Carga Tumoral
18.
Growth Horm IGF Res ; 22(1): 42-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22269954

RESUMO

The objective of this study was to investigate the relation between growth hormone (GH) and attentional electro-cortical responses to task-relevant stimuli (N2b), target detections, speed of responding, P300 latencies, and performance on neuropsychological tests in 19 patients who received external beam radiation therapy for brain tumors in adulthood. In addition, we studied the association between IGF-I and activation of the motor cortex responses (lateralized readiness potential, LRP). Brain function was assessed using event-related potentials (ERPs) during a go/no go selective-attention task, including N2b, P300 and selective motor preparation as reflected in the LRP. Correlations were calculated between peak GH levels after a standardized growth hormone-releasing hormone (GHRH)-arginine test, plasma IGF-I, and cognitive functions. We separately studied four patients who were diagnosed with GHD according to the GHRH-arginine test. Performance on WAIS digit span backward and the Rey-Osterrieth complex figure test correlated positively with GH peak. GHD patients performed worse than non-GHD patients on Stroop interference, trail making B/A attentional shifting and Rey-Osterrieth complex figure test. At trend-level significance, trails A performance was better in patients with lower GH levels and higher radiation doses, and GHD participants detected fewer targets in the go/no go selective attention task. N2b was not significantly altered by GH status. Furthermore, plasma IGF-I was positively correlated with the sum of digit span forward and backward. No relations with P300 were observed. In this study only 21% (4/19) of the patients who received fractionated radiotherapy for a non-endocrine brain tumor were diagnosed with GHD. GHD in these patients was associated with impaired interference control, attentional shifting, and visual long-term memory. The results for interference control and attentional shifting suggest an additional effect of the radiation history.


Assuntos
Transtornos Cognitivos/psicologia , Irradiação Craniana/efeitos adversos , Hormônio do Crescimento Humano/metabolismo , Lesões por Radiação/psicologia , Adulto , Idoso , Transtornos Cognitivos/etiologia , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/etiologia
19.
Br J Cancer ; 103(1): 29-35, 2010 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-20517307

RESUMO

BACKGROUND: The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) can cause resistance to the alkylating drug temozolomide (TMZ). The purpose of this study was to determine the relationship between the MGMT status, determined by means of several techniques and methods, and the cytotoxic response to TMZ in 11 glioblastoma multiforme (GBM) cell lines and 5 human tumour cell lines of other origins. METHODS: Cell survival was analysed by clonogenic assay. The MGMT protein levels were assessed by western blot analysis. The MGMT promoter methylation levels were determined using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) and quantitative real-time methylation-specific PCR (qMSP). On the basis of the results of these techniques, six GBM cell lines were selected and subjected to bisulphite sequencing. RESULTS: The MGMT protein was detected in all TMZ-resistant cell lines, whereas no MGMT protein could be detected in cell lines that were TMZ sensitive. The MS-MLPA results were able to predict TMZ sensitivity in 9 out of 16 cell lines (56%). The qMSP results matched well with TMZ sensitivity in 11 out of 12 (92%) glioma cell lines. In addition, methylation as detected by bisulphite sequencing seemed to be predictive of TMZ sensitivity in all six cell lines analysed (100%). CONCLUSION: The MGMT protein expression more than MGMT promoter methylation status predicts the response to TMZ in human tumour cell lines.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ilhas de CpG , Dacarbazina/farmacologia , Glioblastoma/patologia , Humanos , Técnicas de Amplificação de Ácido Nucleico , Temozolomida
20.
Gynecol Oncol ; 117(2): 281-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20170944

RESUMO

OBJECTIVE: The aim of this study was to determine prevalence of and experienced distress from pelvic floor symptoms in cervical cancer survivors (CCS). METHODS: For this cross-sectional matched cohort study, we matched CCS, treated in the Academic Medical Center, Amsterdam between 1997 and 2007, to a random female population sample aged 20 to 70 years (reference group). We assessed prevalence of and distress from bladder and bowel symptoms with validated pelvic-floor-related questionnaires. Severe distress was defined as values above the 90th percentile of reference group's symptom domain scores. RESULTS: One-hundred and forty-six CCS underwent radical hysterectomy and pelvic lymph node dissection (RH and LND), 49 underwent surgery and adjuvant radiotherapy (SART), and 47 underwent primary radiotherapy (PRT). Urinary incontinence and obstructive voiding were reported by each treatment group more frequently than by the reference group and caused more distress. Patients treated with RH and LND reported more distress from most uro-genital symptoms, except from overactive bladder symptoms. Patients treated with PRT reported more distress from each uro-genital symptom than matched controls. The RH and LND group reported more distress from constipation and obstructive defecation than the reference group. Patients who underwent primary or adjuvant radiotherapy reported more distress from anal incontinence than their matched controls. CONCLUSIONS: Treatment of cervical cancer impairs pelvic floor function. Patients treated with PRT report the most adverse effects on pelvic floor function. The results of our study enable physicians to counsel accurately about specific symptoms. Furthermore, to facilitate referral to pelvic floor specialists when bothersome symptoms occur, we recommend evaluating pelvic floor symptoms as a standard during follow-up.


Assuntos
Constipação Intestinal/etiologia , Incontinência Fecal/etiologia , Incontinência Urinária/etiologia , Neoplasias do Colo do Útero/complicações , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Diafragma da Pelve , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia
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