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1.
Ann Oncol ; 23(11): 2948-2953, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22718135

RESUMO

BACKGROUND: Several French, Belgian and Dutch radiation oncologists have reported good results with the combination of limited surgery after external beam radiotherapy (EBRT) followed by brachytherapy in early-stage muscle-invasive bladder cancer. PATIENTS AND METHODS: Data from 12 of 13 departments which are using this approach have been collected retrospectively, in a multicenter database, resulting in 1040 patients: 811 males and 229 females with a median age of 66 years, range 28-92 years. Results were analyzed according to tumor stage and diameter, histology grade, age and brachytherapy technique, continuous low-dose rate (CLDR) and pulsed dose rate (PDR). RESULTS: At 1, 3 and 5 years, the local recurrence-free probability was 91%, 80% and 75%, metastasis-free probability was 91%, 80% and 74%, disease-free probability was 85%, 68% and 61% and overall survival probability was 91%, 74% and 62%, respectively. The differences in the outcome between the contributing departments were small. After multivariate analysis, the only factor influencing the local control rate was the brachytherapy technique. Toxicity consisted mainly of 24 fistula, 144 ulcers/necroses and 93 other types. CONCLUSIONS: EBRT followed by brachytherapy, combined with limited surgery, offers excellent results in terms of bladder sparing for selected groups of patients suffering from bladder cancer.


Assuntos
Braquiterapia , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias da Bexiga Urinária/cirurgia , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Carcinoma de Células de Transição/radioterapia , Carcinoma de Células de Transição/cirurgia , Terapia Combinada , Cistectomia , Cistotomia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida , Bexiga Urinária/patologia , Bexiga Urinária/cirurgia
2.
Strahlenther Onkol ; 188(4): 305-10, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22349713

RESUMO

PURPOSE: The aim of this analysis was to compare the biochemical no evidence of disease (bNED) rates in low-risk prostate cancer patients treated at two centers of excellence using different approaches: seed brachytherapy (BT) and external beam radiotherapy (EBRT). MATERIALS AND METHODS: A total of 919 low-risk prostate cancer patients, treated from 1998-2008, were identified in the two databases. In Utrecht, 667 patients received I-125 BT applying a dose of 144 Gy. In Vienna, 252 patients were treated with EBRT, applying a local dose of 70 Gy in 82 patients and 74 Gy in 170 patients. bNED rates (Phoenix definition) were assessed. RESULTS: The median follow-up was 46 months (range 1-148 months). The 5-year actuarial bNED rates were 94% for BT patients and 88% for EBRT patients (p = 0.002)-84% for patients receiving 70 Gy and 91% for patients receiving 74 Gy, respectively. In the univariate analysis, patients receiving 70 Gy showed significantly worse outcome compared to BT (p = 0.001) and a difference close to significance compared to 74 Gy (p = 0.06). In the multivariate analysis including tumor stage, Gleason score, initial PSA, hormonal therapy, and dose, patients receiving 70 Gy EBRT showed significantly worse bNED rates compared to BT patients. CONCLUSION: Low-risk prostate cancer patients receiving 74 Gy by EBRT show comparable biochemical control rates to patients receiving seed brachytherapy, whereas patients receiving 70 Gy show significantly worse outcome.


Assuntos
Braquiterapia/métodos , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/métodos , Idoso , Biomarcadores Tumorais/sangue , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica
3.
Ned Tijdschr Geneeskd ; 152(32): 1771-5, 2008 Aug 09.
Artigo em Holandês | MEDLINE | ID: mdl-18754308

RESUMO

--A national, multidisciplinary practice guideline was developed concerning diagnosis and treatment of patients with prostate cancer. Because of the lack of sufficient scientific evidence at this moment no practice guideline on screening is included. --The diagnosis of prostate cancer is made by transrectal ultrasound-guided prostate biopsies. The Gleason score is used for histological grading. --In localized prostate cancer and comorbidity 'active surveillance' is advised if the life expectancy is < 10 years. In healthy patients radical prostatectomy, external and internal radiotherapy are equivalent treatment options. The final decision is made after the patient has received adequate counselling. --In locally advanced prostate cancer in a patient with a life expectancy > or = 10 years external beam radiotherapy is the preferred treatment whether or not in combination with hormonal therapy. --In locally recurring prostate cancer following radical prostatectomy and prostate-specific antigen (PSA) < 1.0 ng/ml salvage radiotherapy can be advised. Recurrence following external beam radiotherapy may be treated by salvage radical prostatectomy or brachytherapy in selected cases. --In metastatic prostate cancer androgen deprivation therapy is advised, i.e. surgical castration, luteinizing hormone-releasing hormone (LH-RH) analogues, or parenteral estrogens. --In hormone resistant prostate cancer palliative treatment of painful metastases is advised, e.g. painkillers, local radiotherapy, or radionuclides. The role of docetaxel-based chemotherapy should be discussed. --During follow-up PSA is determined; digital rectal examination and imaging are performed whenever indicated.


Assuntos
Oncologia/normas , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Braquiterapia/métodos , Terapia Combinada , Humanos , Expectativa de Vida , Masculino , Estadiamento de Neoplasias , Países Baixos , Antígeno Prostático Específico/análise , Prostatectomia , Neoplasias da Próstata/patologia , Sociedades Médicas
4.
Anticancer Res ; 26(1B): 495-505, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16739310

RESUMO

AIM: To define the best sequence of radiotherapy and chemotherapy for inoperable stage III non-small cell lung (NSCL) tumours. MATERIALS AND METHODS: A systematic review was performed on the clinical results of radiotherapy, combined or not with chemotherapy, for inoperable NSCL cancer stage III. The mean median survival time (MST) and mean overall survival (OS) percentages were derived for radiotherapy only, for sequential and for concurrent chemo-radiotherapy. RESULTS: The mean median survival duration +/- standard deviation for radiotherapy only was 10.4 +/- 1.8 months. For sequential chemo- and radiotherapy it was increased to 13.0 +/- 1.2 months. When radiotherapy in the sequential regimen was accompanied by chemotherapy, the mean median duration was 15.8 +/- 2.6 months. For concurrent radio-chemotherapy it was further increased to 16.4 +/- 2.7 months. The mean 2- and 3-year overall survivals for radiotherapy alone, sequential and concurrent radio-chemotherapy were 17.1 +/- 4.6 and 10, 23.8 +/- 6.3 and 18.5 +/- 7.0, and 32.5 +/- 8.7 and 25.7 +/- 6.3%, respectively. CONCLUSION: Concurrent chemo-radiotherapy demonstrated increased efficacy over sequential chemotherapy and radiotherapy and should be the treatment of choice. Further improvements may be obtained by optimising the conditions for concurrent chemo-radiotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Fracionamento da Dose de Radiação , Esquema de Medicação , Humanos , Neoplasias Pulmonares/patologia , Metanálise como Assunto , Estadiamento de Neoplasias , Taxa de Sobrevida
5.
Phys Med Biol ; 51(4): 891-902, 2006 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-16467585

RESUMO

The purpose of this study is to develop and test a tapping device for needle insertion for prostate brachytherapy. This device will tap the needle into the prostate with a certain, well-defined, amount of momentum, instead of the currently used method of pushing the needle. Because of the high needle insertion velocity, we expect prostate motion and deformation to be less compared to current methods. We measured the momentum that is applied when manually tapping the needle into the prostate and found a mean momentum of 0.50 +/- 0.07 N s. The tapping device is pneumatically driven and we found that the delivered momentum increased linearly with the applied air pressure. The efficacy of the tapping device was tested on a piece of beef, placed on a freely moving and rotating platform. A significant correlation was found between the applied pressure and the rotation and displacement of the beef. Displacements and rotations were minimal for the highest pressure (4 bar) and amounted to only 2 mm and 6 degrees, respectively. Higher air pressures will further reduce displacements and rotations.


Assuntos
Braquiterapia/instrumentação , Agulhas , Neoplasias da Próstata/radioterapia , Implantação de Prótese/instrumentação , Robótica/instrumentação , Transdutores , Braquiterapia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Masculino , Implantação de Prótese/métodos , Robótica/métodos , Estresse Mecânico
6.
Anticancer Res ; 25(6C): 4655-61, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16334157

RESUMO

UNLABELLED: The aim of this study was to investigate the influence of the duration of waiting time between the end of induction chemotherapy and the start of radiotherapy on tumour control probability (TCP). PATIENTS AND METHODS: Twenty-three patients with inoperable stage III non-small cell lung cancer (NSCLC) received induction chemotherapy followed by radiotherapy. The mean waiting period between the end of induction chemotherapy and the start of radiotherapy was 80 days; in this period, the median tumour volume increased by a factor of about 6. The Poisson model for TCP and the linear-quadratic model were used to calculate changes in TCP in the waiting time. RESULTS: The 2-year survival of patients treated with curative intent was 8%, lower than the mean value of 26% derived from other studies. Assuming that radiotherapy started on the day of restaging or on the first day of radiotherapy (RT1), the calculated mean TCP at restaging was 13.3% and at RT1 was 0.5% for patients treated with curative intent. CONCLUSION: The calculated TCP decreased in the waiting period from 13.3 to less than 1%. Hence, the relatively long interval time between chemo- and radiotherapy had a deleterious effect on local control. We recommend the waiting time to be as short as possible.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Interpretação Estatística de Dados , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Estadiamento de Neoplasias , Tolerância a Radiação , Taxa de Sobrevida , Resultado do Tratamento
8.
BJU Int ; 93(1): 36-41, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14678364

RESUMO

OBJECTIVE: To report an interim clinical evaluation of combined external beam irradiation (EBRT) and interstitial or regional hyperthermia in the treatment of locally advanced prostate cancer. PATIENTS AND METHODS: From 1997 to 2001, 26 patients with T3-4/NX/0M0 prostate carcinoma were treated with a combination of conformal EBRT and hyperthermia. Fourteen patients received five weekly regional hyperthermia treatments within an optimization (phase II) study, using the coaxial transverse electrical magnetic system. Twelve patients received one interstitial hyperthermia treatment within a feasibility study (phase I), using the multi-electrode current source system. Irradiation was delivered using a conformal three-field technique, administering 70 Gy in 2-Gy fractions in 7 weeks. RESULTS: The mean initial prostate-specific antigen level was 26 ng/mL. Three patients had a T4 and 23 a T3 tumour; the tumours were classified as well (four), moderately (16) and poorly (six) differentiated. The mean follow-up was 36 months. In the combined treatments there was no toxicity of more than grade 2. In regional hyperthermia the mean index temperature (T90 and T50, i.e. exceeded by 90% and 50% of the measurements) was 40.2 degrees C and 40.8 degrees C, and for interstitial hyperthermia 39.4 degrees C and 41.8 degrees C, respectively. All patients survived; seven patients had a biochemical relapse (27%), three in the regional and four in the interstitial group. The actuarial probability of freedom from biochemical relapse was 70% at 36 months for all patients together, 79% for regional and 57% for interstitial. No factors were found that could be used to predict relapse. CONCLUSIONS: The clinical outcome in these patients with advanced localized prostate cancer seems to compare favourably with most series using irradiation alone, and the treatment caused no severe complications.


Assuntos
Hipertermia Induzida/métodos , Neoplasias da Próstata/terapia , Idoso , Terapia Combinada/métodos , Intervalo Livre de Doença , Estudos de Viabilidade , Seguimentos , Humanos , Hipertermia Induzida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/radioterapia , Resultado do Tratamento
9.
Neth Heart J ; 12(9): 389-393, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25696369

RESUMO

DESIGN: Prospective, randomised single-centre pilot study comparing a beta with a gamma source and a sirolimus-eluting stent in patients with an estimated high risk of restenosis (40 to 50%). PURPOSE: Although the majority of patients referred for revascularisation are now being treated with percutaneous coronary intervention (PCI) combined with stenting, a small number still suffer from recurrent restenosis which can be invalidating for the patient and frustrating for the cardiologist due to repeated PCIs. In this prospective single-centre pilot study we will test the hypothesis of three different treatment strategies to use in this special patient subset, to determine if we can find a positive 'trend' in one arm, in order to either make a selection for one of the treatment strategies, or to provide a base to expand the study into a larger multicentre randomised study. TIME COURSE AND ENROLLMENT: A total of 120 patients will be included, 40 in each treatment arm. All patients with either in-stent and/or native restenosis and/or diabetics and/or type C lesions (ACC/AHA) are eligible. The usual exclusion criteria for intracoronary brachytherapy and prolonged antiplatelet therapy are applied. All lesions <44 mm in length and with a vessel diameter 2.4>4.0 mm are suitable. Angiographic, intravascular ultrasound imaging and clinical follow-up at one year will become available in the first quarter of 2005.

10.
Br J Cancer ; 89(12): 2184-9, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14676792

RESUMO

Induction chemotherapy of non-small-cell lung cancer (NSCLC) stage III with gemcitabine and cisplatin for downstaging of the tumour with the aim for further treatment with ionising radiation is one of the treatments for lung cancer patients. The purpose of this study was to investigate the influence of the waiting time for radiotherapy, that is, the interval between induction chemotherapy and radiotherapy, on the rate of tumour growth for patients with NSCLC. Interval times between the end of induction chemotherapy and date of diagnostic CT, planning CT and first day of radiotherapy were determined for 23 patients with NSCLC. Increase in gross tumour volume was measured for 18 patients by measuring the dimensions of the primary tumour and lymph node metastases on the diagnostic CT after induction chemotherapy and on the CT used for radiotherapy planning. For each patient, the volume doubling time was calculated from the time interval between the two CTs and ratio of the gross volumes on planning CT and diagnostic CT. The mean time interval between end of chemotherapy and day of diagnostic CT was 16 days, and till first day of radiotherapy 80.3 (range 29-141) days. In all, 41% of potentially curable patients became incurable in the waiting period. The ratio of gross tumour volumes of the two CTs ranged from 1.1 to 81.8 and the tumour doubling times ranged from 8.3 to 171 days, with a mean value of 46 days and median value of 29 days. This is far less than the mean doubling time of NSCLC in untreated patients found in the literature. This study shows that in the time interval between the end of induction chemotherapy and the start of radiotherapy rapid tumour progression occurs as a result of accelerated tumour cell proliferation: mean tumour doubling times are much shorter than those in not treated tumours. As a consequence, the gain obtained with induction chemotherapy with regard to volume reduction was lost in the waiting time for radiotherapy. We recommend diminishing the time interval between chemo- and radiotherapy to as short as possible.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Divisão Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Terapia Combinada , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/fisiopatologia , Neoplasias Pulmonares/radioterapia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Indução de Remissão , Fatores de Tempo , Tomografia Computadorizada por Raios X , Gencitabina
11.
Int J Hyperthermia ; 19(5): 481-97, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12944164

RESUMO

A study was performed on regional hyperthermia for patients with locally advanced prostate carcinoma. The primary objective was to analyse the thermometry data with an emphasis on the possibility of replacing invasive thermometry by tumour-related intra-luminal thermometry. Fourteen patients were treated with a combination of conformal external beam radiotherapy (70 Gy) and hyperthermia. Hyperthermia was delivered using the Coaxial TEM system, one treatment per week, to a total of five treatments. Thermometry was performed in bladder, urethra, rectum and esophagus. Invasive thermometry in the prostate was carried out during one or two treatments for each patient by placing transperineally a central and a peripheral catheter. Heterogeneous temperature distributions were measured in the prostate. The mean average invasive temperature range was 1.1 degrees C. Due to the temperature heterogeneity and a limited number of thermometry sensors (mean 7, range 2-13), large variability between treatments and patients existed regarding achieved temperatures and dose. The mean invasive T90 was 40.2 +/- 0.6 degrees C and T50 was 40.8 +/- 0.6 degrees C. The mean Cum min T90>40.5 degrees C per treatment was 22 (range 0-50). Importantly, intra-luminal temperatures did not reliably predict invasively measured temperatures. Invasive thermometry, therefore, remains compulsory to calculate a thermal dose for an individual patient. Changes in temperature during treatment, measured by the urethral sensors, corresponded well with changes in temperature measured by the individual invasive sensors. Similar comparison of rectal temperature changes with intra-prostatic temperature changes was not as predictive. The similarity in temperature changes between the urethral and interstial sites, suggests that urethral temperatures are sufficient for treatment optimization. The SAR profile did not correspond with the temperature profile indicating heterogeneous perfusion. Although regional hyperthermia in combination with external beam radiotherapy for locally advanced prostate carcinoma is clinically feasible, the question on the importance of invasive thermometry remains.


Assuntos
Hipertermia Induzida/métodos , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional , Termômetros , Idoso , Temperatura Corporal , Terapia Combinada , Esôfago , Estudos de Viabilidade , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Reto , Uretra
12.
Int J Hyperthermia ; 19(4): 402-13, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12850926

RESUMO

INTRODUCTION: The aim of this prospective study was to describe quality of life (QoL) in patients with locally advanced prostate carcinoma treated with conventional radiotherapy and to evaluate the influence of adding regional or interstitial hyperthermia. MATERIALS AND METHODS: All patients were irradiated using a CT-planned conventional three field technique, administering 70 Gy to prostate and vesicles. In two different phase I studies, hyperthermia was added to the radiotherapy. Twelve patients were treated with one interstitial hyperthermia treatment, lasting 60 min. Fourteen patients have been treated with five regional hyperthermia treatments, lasting 75 min each. In both hyperthermia studies, the body, bladder and rectum temperatures remained below safety limits. Patients treated with radiotherapy alone (n = 58) or combined with regional (n = 8) or interstitial hyperthermia (n = 12) completed the European Organization for Research and Treatment of Cancer (EORTC) core questionnaire (C30 + 3), the EORTC prostate cancer module (PR25) and the Rand 36 health survey before treatment and 1 and 6 months after completion of treatment. Analysis of Variance (ANOVA) for repeated measurements has been performed to describe the data. RESULTS: All patient groups were comparable concerning patient characteristics. No significant interaction or difference in QoL has been noticed between the two hyperthermia patient groups and the patient group without hyperthermia. Therefore, all groups were analysed together (n = 78) to detect QoL changes in time. A deterioration of QoL has been measured from baseline to 1 month after treatment. Fatigue, pain, urinary symptoms, bowel symptoms and financial difficulties increased significantly. Social, physical and role functioning worsened significantly. No differences in QoL were measured 6 months after treatment compared to the baseline measurement, except for a decrease in sexual activity. CONCLUSIONS: After radiotherapy with or without hyperthermia only a temporary deterioration of QoL occurs, concerning social, psychological and disease related symptoms. Additional hyperthermia does not seem to decrease QoL.


Assuntos
Hipertermia Induzida , Neoplasias da Próstata/fisiopatologia , Neoplasias da Próstata/terapia , Qualidade de Vida , Radioterapia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/psicologia , Inquéritos e Questionários
13.
Int J Radiat Oncol Biol Phys ; 51(4): 938-46, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11704314

RESUMO

PURPOSE: To study the radiation tolerance of the parotid glands as a function of dose and volume irradiated. METHODS AND MATERIALS: One hundred eight patients treated with primary or postoperative radiotherapy for various malignancies in the head-and-neck region were prospectively evaluated. Stimulated parotid flow rate was measured before radiotherapy and 6 weeks, 6 months, and 1 year after radiotherapy. Parotid gland dose-volume histograms were derived from CT-based treatment planning. The normal tissue complication probability model proposed by Lyman was fit to the data. A complication was defined as stimulated parotid flow rate <25% of the preradiotherapy flow rate. RESULTS: The mean stimulated preradiotherapy flow rate of 174 parotid glands was 0.34 mL/min. The mean flow rate reduced to 0.12 mL/min 6 weeks postradiotherapy, but recovered to a mean flow rate of 0.20 mL/min at 1 year after radiotherapy. Reduction in postradiotherapy flow rate correlated significantly with mean parotid dose. No threshold dose was found. Increasing the irradiated volume of parotid glands from 0%-40% to 90-100% in patients with a mean parotid dose of 35-45 Gy resulted in a decrease in flow ratio from, respectively, approximately 100% to less than 10% 6 weeks after radiation. The flow ratio of the 90%-100% group partially recovered to 15% at 6 months and to 30% at 1 year after radiotherapy. The normal tissue complication probability model parameter TD(50) (the dose to the whole organ leading to a complication probability of 50%) was found to be 31, 35, and 39 Gy at 6 weeks, 6 months, and 1 year postradiotherapy, respectively. The volume dependency parameter n was around 1, which means that the mean parotid dose correlates best with the observed complications. There was no steep dose-response curve (m = 0.45 at 1 year postradiotherapy). CONCLUSIONS: This study on dose/volume/parotid gland function relationships revealed a linear correlation between postradiotherapy flow ratio and parotid gland dose and a strong volume dependency. No threshold dose was found. Recovery of parotid gland function was shown at 6 months and 1 year after radiotherapy. In radiation planning, attempts should be made to achieve a mean parotid gland dose at least below 39 Gy (leading to a complication probability of 50%).


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Glândula Parótida/efeitos da radiação , Saliva/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Relação Dose-Resposta à Radiação , Feminino , Humanos , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Glândula Parótida/metabolismo , Probabilidade , Estudos Prospectivos , Tolerância a Radiação , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X
14.
Praxis (Bern 1994) ; 90(36): 1501-5, 2001 Sep 06.
Artigo em Alemão | MEDLINE | ID: mdl-11593905

RESUMO

At the Utrecht University Hospital Netherlands the preliminary results of perineal implantation of I-125 seeds in patients with cancer of the prostate were evaluated prospectively. In the period from October 1989 to December 1998, a total of 249 patients with localized carcinoma of the prostate were treated with perineal implantation of I-125 seeds. Follow-up was every 3-6 months. Results regarding progression and complicantions were collected prospectively. Progression of the disease was observed in 54 patients: 13 died from carcinoma, 41 are living with proven relapse. 18 died from intercurrent disease. 25 developed a local recurrence, 22 a distant relapse, 19 patients only showed a rise of prostate specific antigen level, without further symptoms. Acute side effects from the urethra were observed in 22 patients: prolonged dysuria in 18, acute retention in 4 and urethral stenosis in 3.9 patients had surgical treatment of micturition disorders. Four patients suffered from reversible intestinal problems. Summarizing perineal I-125 implantation causes few complications and may constitute an alternative to external irradiation as well as to radical prostatectomy in the treatment of localized carcinoma of the prostate.


Assuntos
Braquiterapia , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Países Baixos , Estudos Prospectivos , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Taxa de Sobrevida , Resultado do Tratamento
15.
Phys Med Biol ; 46(12): 3115-31, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11768495

RESUMO

To determine the thermal dose of a hyperthermia treatment, knowledge of the three-dimensional (3D) temperature distribution is mandatory. The aim of this paper is to validate an interstitial hyperthermia treatment planning system with which the full 3D temperature distribution can be obtained in individual patients. Within a phase I study, 12 patients with prostate cancer were treated with interstitial hyperthermia using our multi electrode current source interstitial hyperthermia treatment (MECS IHT) system. The temperature distribution was measured from within the heating devices and by additional thermometry. The perfusion level was estimated and the heating implant reconstructed. The steady-state temperature distribution was calculated using our interstitial hyperthermia treatment planning system. The simulated temperature distribution was validated by individually comparing the measured and simulated thermo-sensors, both for the thermometry integrated with the heating applicators and the additional thermometry. The entire procedure was also performed on a no-flow agar-agar phantom. It was shown that the calculated temperature distribution of an individual patient during MECS interstitial hyperthermia is very heterogeneous. The validation indicates that the calculated temperature elevations match the measurements within approximately 1 degrees C. Possible improvements are more precise reconstruction, incorporation of discrete vasculature and using a temperature-dependent, heterogeneous perfusion distribution. Further technical improvements of the MECS-IHT system may also result in better temperature calculations.


Assuntos
Carcinoma/terapia , Hipertermia Induzida/métodos , Neoplasias da Próstata/terapia , Ágar/química , Calibragem , Eletrodos , Humanos , Masculino , Imagens de Fantasmas , Reprodutibilidade dos Testes , Temperatura , Fatores de Tempo
16.
Radiother Oncol ; 57(3): 269-72, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104884

RESUMO

BACKGROUND AND PURPOSE: I-125 seed implantation is one of the treatment modalities for localized prostate carcinoma. It has few side-effects compared with radical prostatectomy and beam irradiation. MATERIALS AND METHODS: At the University Medical Centre, Utrecht, 249 naive patients were treated by perineal implantation between December 1989 and December 1998. Mean age was 69 years (range 45-91 years). Stage and grade were: T(1), 121; T(2), 126; T(3), 2; well differentiated, 136; moderate, 100; undifferentiated, 15; not established, 8. Mean initial PSA level was 16.1 ng/ml (range <1.0-165). Mean prostate volume was 33 cm(3). Sixty-two patients had had previous surgical intervention for voiding problems. Treatment evolved from single seeds to RAPID Strand, and from a probe-mounted template to stepping unit and pre-planning. The introduction of RAPID Strand considerably increased the number of seeds (mean 41->65 seeds). Mean follow-up was 32.8 months, median 29.2 months (range 6-94 months). RESULTS: A total of 195 patients had no evidence of disease (18 died of intercurrent causes) and 54 had evidence of disease (13 died with prostate cancer). Toxicity was found in 22 patients. Urinary side-effects occurred in 18 patients, in nine cases after previous TURP. Four patients had intestinal problems, but only one had a rectal ulcer, which healed after hormonal therapy for local recurrence. CONCLUSIONS: Our findings indicate a correlation between the number of seeds implanted per cm(3) prostate volume and the final result. This is also reflected in a better volume coverage from MRI studies.


Assuntos
Braquiterapia , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Seguimentos , Humanos , Radioisótopos do Iodo/efeitos adversos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Resultado do Tratamento
17.
Radiother Oncol ; 57(3): 279-84, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104886

RESUMO

BACKGROUND AND PURPOSE: To investigate prostate dose coverage and overdosage in planned and realized permanent iodine seed prostate implants and to explore the use of the natural dose-volume histogram (NDVH) and the cumulative dose-volume histogram (CDVH) as tools to optimize prostate implants. MATERIALS AND METHODS: The optimal prescription dose (PD) or natural prescription dose (NPD) was derived from the NDVH. The mismatch between the NPD and the given PD was called the natural dose ratio (NDR). For an ideal implant the NDR should be 1. The target is overdosed if NDR >1 and underdosed if NDR <1. The NDR and prostate coverage were evaluated in implants of nine patients. Prostate coverage was determined from the CDVH based on pre-implant ultrasound or post-implant MRI for the planned and realized implants, respectively. The use of the NDVH to further optimize the planned prostate implants was also explored. RESULTS: The mean values of the NDRs were 1.30+/-0.34 (range 0.76-1.79), 1.22+/-0.31 (0.76-1.74) and 1.22+/-0.12 (0.98-1.33) for the planned, realized and optimized seed distributions, respectively. The realized prostatic implants showed smaller prostate coverage than the planned implants. The prostate volume fractions receiving 100% of the prescription dose were V(100)=79+/-6% and V(100)=97+/-3% for the realized and the planned implants, respectively. CONCLUSIONS: The NDVH and the CDVH proved to be valuable tools in plan evaluation. The NDVH and its derived parameter NDR quantify the risk of under or overdosage for a given PD. The CDVH is valuable in evaluation of prostate coverage realized prostate. Our strategy to implant just the prostate and not the prostate plus a margin led to NDR values between 1.1 and 1.3 and a prostate coverage of V(100)=79+/-6% in the nine patients. The planned coverage of V(100)=95% was not realized, mainly due to inadequate coverage of the base of the prostate.


Assuntos
Braquiterapia , Neoplasias da Próstata/radioterapia , Humanos , Masculino , Próstata/efeitos da radiação , Dosagem Radioterapêutica
18.
Radiother Oncol ; 57(3): 297-300, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104889

RESUMO

BACKGROUND AND PURPOSE: Permanent seed implantation was used in the management of primary and recurrent prostate cancer in patients who had been treated previously by radiotherapy of the true pelvis. MATERIAL AND METHODS: Between 1993 and 1998 a total of 21 patients received an I-125 implant after radiotherapy for bladder cancer (two patients), anal cancer (one patient), seminoma (two patients) and prostate cancer (16 patients). Two seminoma and 10 prostate cancer patients were treated after earlier definitive external beam radiation therapy (EBRT), while the bladder and anal cancer were initially treated with EBRT plus iridium implantation. Six prostate cancer patients were initially treated by brachytherapy alone. The interval between the two treatments was longer in patients with radiotherapy for other malignancies than prostate cancer. RESULTS: After EBRT no serious late toxicity was observed. However, 1/6 patients who had two seed implants experienced serious complications, resulting in a vesico-rectal fistula. CONCLUSIONS: The permanent seed implantation with I-125 is feasible after previous radiotherapy in the prostate area. Also a second implant is possible, but may result in severe complications, depending on the initial dose and interval between the two treatments.


Assuntos
Braquiterapia , Pelve/efeitos da radiação , Neoplasias da Próstata/radioterapia , Neoplasias do Ânus/radioterapia , Braquiterapia/efeitos adversos , Progressão da Doença , Estudos de Viabilidade , Humanos , Masculino , Recidiva Local de Neoplasia/radioterapia , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Neoplasias Testiculares/radioterapia , Neoplasias da Bexiga Urinária/radioterapia
19.
Int J Radiat Oncol Biol Phys ; 48(3): 807-15, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11020578

RESUMO

PURPOSE: To determine prospectively the cataract-free interval (latency time) after total body irradiation (TBI) and bone marrow transplantation (BMT) and to assess accurately the final severity of the cataract. METHODS AND MATERIALS: Ninety-three of the patients who received TBI as a part of their conditioning regimen for BMT between 1982 and 1995 were followed with respect to cataract formation. Included were only patients who had a follow-up period of at least 23 months. TBI was applied in one fraction of 8 Gy or two fractions of 5 or 6 Gy. Cataract-free period was assessed and in 56 patients, who could be followed until stabilization of the cataract had occurred, final severity of the cataract was determined using a classification system. With respect to final severity, two groups were analyzed: subclinical low-grade cataract and high-grade cataract. Cataract-free period and final severity were determined with respect to type of transplantation, TBI dose, and posttransplant variables such as graft versus host disease (GVHD) and steroid treatment. RESULTS: Cataract incidence of the analyzed patients was 89%. Median time to develop a cataract was 58 months for autologous transplanted patients. For allogeneic transplanted patients treated or not treated with steroids, median times were 33 and 46 months, respectively. Final severity was not significantly different for autologous or allogeneic patients. In allogeneic patients, however, final severity was significantly different for patients who had or had not been treated with steroids for GVHD: 93% versus 35% high-grade cataract, respectively. Final severity was also different for patients receiving 1 x 8 or 2 x 5 Gy TBI, from patients receiving 2 x 6 Gy as conditioning therapy: 33% versus 79% high-grade cataract, respectively. The group of patients receiving 2 x 6 Gy comprised, however, more patients with steroid treatment for GVHD. So the high percentage of high-grade cataract in the 2 x 6 Gy group might also have been caused to a significant extent by steroid treatment. The percentage of patients with high-grade cataract was lower in allogeneic transplanted patients without steroid treatment for GVHD than in autologous transplanted patients: 35% versus 48%. An explanation for this could be pretransplant therapy containing high-dose steroids. CONCLUSIONS: After high-dose-rate TBI in one or two fractions, steroids for GVHD influence latency time of a cataract and are of great importance for the severity the cataract finally attains. Although a cataract will develop in all patients, a clinically important high-grade cataract is relatively infrequent in patients not treated with steroids. Pretransplant therapy might also influence final severity of cataract.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Catarata/etiologia , Condicionamento Pré-Transplante/efeitos adversos , Irradiação Corporal Total/efeitos adversos , Adolescente , Adulto , Ciclofosfamida/uso terapêutico , Ciclosporina/uso terapêutico , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Transplante Autólogo , Transplante Heterólogo
20.
Oral Oncol ; 36(1): 54-60, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10889920

RESUMO

Knowledge about the influence of biomarkers on cell proliferative activity might explain differences in radiosensitivity between head and neck tumors and might improve patient selection for the most optimal treatment strategy. p53 and bcl-2 protein expression were determined immunohistochemically in 56 head and neck cancer patients, treated by surgery only in five cases and by radiotherapy, with or without surgery, in 51 cases. Relationships with various cell proliferation markers, determined by flow-cytometry (G1-phase fraction, S-phase fraction, BrdUrd-labeling index, duration of S-phase and potential doubling time) were investigated. Associations between these cell proliferation parameters, on the one hand, and both p53 and bcl-2, on the other, were not found. Furthermore, p53 and bcl-2 expression were both not related to clinicopathological parameters (T- and N-stage, site, grade) and did not affect loco-regional recurrence-free survival and/or disease-free survival. We could not find a prognostic value for both p53 and bcl-2 protein expression to differentiate radiosensitive from radioresistant head and neck tumors.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Divisão Celular , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Resultado do Tratamento
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