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1.
Br J Radiol ; 78(934): 899-905, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16177012

RESUMO

The aim of this work was to evaluate the dosimetric performance of a commercial treatment planning system (TPS) which employs a three-dimensional calculation algorithm (Nucletron Plato version 2.2.3), following the guidelines of the AAPM Task Group 23 (TG23). Seven test cases were used to test the TPS dosimetric performance in homogeneous water. These cases involved absolute dose measurements on central as well as off-axis points situated at various depths, using simple field arrangements, and comparison with corresponding TPS calculations. This comparison yielded differences within +/-2% at all points, for all test cases. To test the ability of the TPS to account for tissue inhomogeneities, corresponding comparisons were performed with the presence of a low-density material in the beam to resemble an air inhomogeneity. Absolute dose measurements and corresponding TPS calculations showed a mean deviation of the order of +/-3.5%, reaching a maximum of 11.5% for small field sizes (5 cm x 5 cm). In summary, observed deviations are well within the set tolerance levels while comparison with previous TPS versions showed that Plato version 2.2.3 is significantly improved, especially in dose calculations in the presence of low density inhomogeneities.


Assuntos
Radioterapia/normas , Calibragem , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica/normas , Valores de Referência
2.
Int J Radiat Biol ; 79(10): 831-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14630542

RESUMO

PURPOSE: To investigate whether amifostine is effective at reducing the yield of chromatid breaks when present during G(2)-phase irradiation of human normal cells and cells from cancer prone patients, as well as to study the mechanisms underlying the radioprotective effect of amifostine. MATERIALS AND METHODS: G(2) chromosomal radiosensitivity in the presence or absence of amifostine was studied in healthy donors, cancer patients, ataxia-telangietasia (A-T) patients and five human lymphoblastoid cell lines with genes predisposing to cancer. The yield of chromatid breaks following gamma-irradiation in G(2) phase was obtained at the subsequent metaphase using the G(2) assay. For scoring chromatid damage directly in G(2) or G(0) phase, premature chromosome condensation was used. RESULTS: When amifostine was present during irradiation, the mean yield of radiation-induced chromatid breaks as visualized by the G(2) assay was significantly reduced in healthy donors (t-test, p=0.001), in cells from cancer patients (p=0.001) and in cell lines from patients with genes predisposing to cancer (p=0.01) except ATM(-/-) (0.1

Assuntos
Amifostina/administração & dosagem , Ataxia Telangiectasia/fisiopatologia , Aberrações Cromossômicas/efeitos dos fármacos , Fase G2/efeitos dos fármacos , Fase G2/efeitos da radiação , Predisposição Genética para Doença/prevenção & controle , Neoplasias/fisiopatologia , Protetores contra Radiação/administração & dosagem , Ataxia Telangiectasia/genética , Linhagem Celular Tumoral , Análise Citogenética , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Neoplasias/genética , Lesões Pré-Cancerosas , Proteção Radiológica/métodos , Tolerância a Radiação/efeitos dos fármacos , Valores de Referência
3.
Ann Oncol ; 14(3): 378-82, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12598341

RESUMO

BACKGROUND: The aim of this study was to determine whether the efficacy of the combination of 5-fluorouracil (5-FU), leucovorin (LV) and radiation therapy (RT) could be improved by the addition of interferon-alpha2b (IFN-alpha) in patients who have had a 'curative' resection, for rectal adenocarcinoma (Dukes' B2/C; T3 N0, T4 N0, N1-3). PATIENTS AND METHODS: A total of 207 eligible patients with a performance status of 0 or 1 were randomized postoperatively between days 21 and 70 to one of the two treatment groups: group A, LV 20 mg/m2 i.v. bolus and 5-FU 425 mg/m2 i.v. days 1-5 and 29-33, LV 20 mg/m2 and 5-FU 400 mg/m2 days 57-60 and 85-88, LV 20 mg/m2 and 5-FU 380 mg/m2 days 1-5 and 29-33 with the second day 1 occurring 28 days after the completion of RT (45 Gy); group B, LV, 5-FU and RT as in group A, and IFN-alpha 5 x 10(6) IU s.c. three times during each week chemotherapy is given. RESULTS: 104 patients were randomized into group A and 103 into group B. There was no statistically significant difference in either disease-free survival or overall survival between the two groups. Toxicity was also the same, except for the flu-like syndrome associated with the IFN-alpha administration. CONCLUSIONS: There was no difference in efficacy between the two combinations. Toxicity was greater with the LV + 5-FU + IFN-alpha regimen because of the flu-like syndrome.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Infusões Intravenosas , Injeções Intravenosas , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Proteínas Recombinantes , Neoplasias Retais/cirurgia , Resultado do Tratamento
4.
Lung Cancer ; 35(2): 203-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11804694

RESUMO

In order to facilitate patients with symptomatic locally advanced NSCLC, especially those coming from remote areas we have employed two palliative RT schedules. The first (S1) is the well known from Medical Research Council (MRC) randomized studies 2 x 8.5 Gy one week apart and the second (S2) is a two-day RT schedule: three fractions of 4.25 Gy are given on the first day and two fractions of 4.25 Gy on the second day. The records of 92 patients were reviewed (48 for S1 and 44 for S2). Patients, disease characteristics and results were similar for both groups; rates of symptom disappearance were for S1 and S2, respectively: cough 24 and 20%, hemoptysis 60 and 67%, chest pain 57 and 64% and dyspnoea 55 and 45% The overall condition improved in 39 and 36%, respectively. The median palliation time in days was in S1 and S2, respectively: cough 70 and 66, haemoptysis 133 and 139, chest pain 68 and 62 and dyspnoea 74 and 69 days. The median survival was 25 weeks in both S1 and S2 groups (P=0.89 log-rank test). At 52 weeks (one year), ten (21%) and seven (16%) of the patients were alive in S1 and S2 groups, respectively. At 104 weeks, the corresponding figures were two (4%) and two (4.7%) for S1 and S2. Our results are in accordance to those reported in literature regarding the safety and efficacy of palliative hypofractionated radiotherapy schemes. Their use in selected patients could be cost-effective and convenient for patients especially those coming from remote areas.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Cuidados Paliativos , Satisfação do Paciente , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Dor no Peito/etiologia , Tosse/etiologia , Fracionamento da Dose de Radiação , Dispneia/etiologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Radioterapia/efeitos adversos , Estudos Retrospectivos , População Rural , Resultado do Tratamento
6.
J Neurooncol ; 50(3): 275-85, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11263508

RESUMO

BACKGROUND: The aim of this study was to show, whether a certain prophylacting applicable radiation affects the cognition, particularly, the specific cognitive components P50, N100, P300 and N400 of auditory event related potentials (ERPs) during a short memory test. METHODS AND MATERIALS: Eleven patients with small cell lung cancer (SCLC), who had presented complete response of disease after chemotherapy and radical radiotherapy in the lung, were prescribed to receive a prophylacting cranial irradiation (PCI) with a 6 MeV linear accelerator. The dose schedule was consisting of a total dose up to 30 Gy in 10 fractions, within 12 days (5 days a week). The psychophysiological approach before and after PCI was assessed by measurements of the auditory ERPs during a short memory performance using the digit-span Wechsler test. Components of ERP were recorded from 15 scalp electrodes. Additionally, symptomatology of depression and anxiety were assessed using Zung Self-Rating Depression Scale and Spielberger Anxiety Inventory, respectively, for pre- and post-PCI. RESULTS: No significant difference was noticed pre- and post-radiotherapy of all particular level of psychophysiological analysis concerning both the latencies and the amplitudes of ERPs auditory components P50, N100, P300 and N400 (P > 0.05, Wilcoxon signed test). Additionally, no changes were found with regard to behavioral performance (memory recall), depression symptomatology and state anxiety, according to pre- and post-radiation measurements. However, the self-reported depression symptomatology showed that the patients presented moderate depression. CONCLUSION: No short-term psychophysiological neurotoxicity was detected with this PCI schedule using these instruments, lending additional support to evidence suggesting the benefit of this certain PCI schedule for patients with SCLC.


Assuntos
Neoplasias Encefálicas/prevenção & controle , Encéfalo/efeitos da radiação , Carcinoma de Células Pequenas/radioterapia , Transtornos Cognitivos/diagnóstico , Neoplasias Pulmonares/radioterapia , Testes Neuropsicológicos , Lesões por Radiação/diagnóstico , Idoso , Neoplasias Encefálicas/secundário , Carcinoma de Células Pequenas/secundário , Transtornos Cognitivos/etiologia , Irradiação Craniana/efeitos adversos , Humanos , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Análise de Sobrevida
8.
J Chemother ; 10(2): 136-40, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9603640

RESUMO

With the purpose of investigating whether the 6-course standard dose treatment of etoposide-platinum (EP) in small cell lung cancer could be reduced to 4 courses without compromising patient's survival, 70 patients were randomized to receive either 4 or 6 cycles of etoposide 120 mg/m2 i.v. days 1-3 and cisplatin 80 mg/m2 day 1. With the intention of comparing these two durations as primary treatment policies, patients were randomized on admission and not after the fourth course. From the 69 evaluable patients 34 received EPx4 cycles and 35 EPx6 cycles. Objective response for EPx4 was achieved by 21 patients (62%, 95% CI 44%-78%) compared to 24 patients (69%, 95% CI 51%-83%) of the EPx6 group. Median times to progression were 6 mo (4-19) and 7 mo (4-40) respectively (P=0.06) in the two groups. Median survivals were 8.5 mo (4-28.5) and 9.5 mo (4-51) (p=0.04) respectively. No differences in the survival of limited-disease patients were shown with 10.5 mo (6-28.5) and 12 mo (8-51) respectively, in the two groups. Patients with extensive disease had a trend favoring prolonged chemotherapy with a median survival of 9 mo (5-16) versus 6.5 mo (4-16.5) for those in the EPx4 group (p=0.09). Toxicity was not significantly more severe in the EPx6 group. In conclusion, patients achieving complete response within 4 cycles may not need continued chemotherapy, but patients with extensive disease may benefit from 2 more cycles.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Pequenas/patologia , Cisplatino/administração & dosagem , Relação Dose-Resposta a Droga , Etoposídeo/administração & dosagem , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Nefropatias/induzido quimicamente , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Indução de Remissão , Análise de Sobrevida
9.
Anticancer Res ; 17(3B): 1767-72, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9179232

RESUMO

The efficacy and toxicity of treatment with 1400 +/- 100 MBq of Re-186-HEDP were evaluated in women with osseous metastatic breast cancer. The follow-up period was fourteen weeks. The efficacy of treatment was assessed by a) a pain and performance questionnaire that patients were asked to complete daily and b) a CT scan comparison of a randomly preselected osseous lesion before and 30 weeks after Re-186-HEDP i.v. application. The response to treatment was also evaluated by using the Kamofsky Index. Two out of fourteen women (14%) experienced loss of pain, 6 experienced obvious and 2 some improvement. No change was observed in 4 patients. Five patients manifested a flare response to treatment, with increase in pain within the first, 4 to 5 days after Re-186-HEDP administration. Five patients showed a decrease in platelet levels and absolute number of polymorphonuclear blood transfusion; no neurologic side effects were observed. Re-186-HEDP appears to be a useful new radiopharmaceutical for pain palliation induced by osseous metastases due to breast cancer. Compared to Sr-89 chloride efficacy, it provides longer-lasting analgesia, and when needed it can be reinjected with less risk due to its improved physico- and radiochemical properties.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias da Mama/radioterapia , Ácido Etidrônico/uso terapêutico , Dor Intratável , Rênio/uso terapêutico , Adulto , Analgesia/métodos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/fisiopatologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/fisiopatologia , Ácido Etidrônico/efeitos adversos , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Compostos Organometálicos , Osteólise , Cuidados Paliativos , Radioisótopos , Rênio/efeitos adversos , Medição de Risco , Estrôncio/efeitos adversos , Estrôncio/uso terapêutico , Medronato de Tecnécio Tc 99m , Tomografia Computadorizada de Emissão
10.
Radiother Oncol ; 38(3): 263-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8693109

RESUMO

For the non-metastatic nasopharyngeal carcinoma, external beam radiation therapy (median dose 64 Gy) and a boost of intracavitary irradiation (ICRT) has been given. Caesium-137 pellets of 40 mCi were used at a dose rate of 3-3.5 Gy/h, 1 cm from the sources. The median dose was 8.5 Gy. Overall 5-year actuarial survival for the 48 studied patients was 60.4% and LRFS was 64%. The procedure was well tolerated by our patients.


Assuntos
Braquiterapia , Carcinoma de Células Escamosas/radioterapia , Radioisótopos de Césio/uso terapêutico , Radioisótopos de Cobalto/uso terapêutico , Neoplasias Nasofaríngeas/radioterapia , Teleterapia por Radioisótopo , Radioterapia de Alta Energia , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Dosagem Radioterapêutica , Taxa de Sobrevida , Fatores de Tempo
13.
Clin Oncol (R Coll Radiol) ; 7(1): 59-61, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7727312

RESUMO

We report a patient with unusual high grade dermatofibrosarcoma protuberans, confirmed by immunohistochemistry, which developed at radiotherapy field margins 5.7 years after radiotherapy for a squamous cell glottic cancer. The sarcoma relapsed locally after inadequate excision and developed lung metastases, as confirmed by fine needle aspiration. Radiotherapy induced soft tissue sarcomas may differ histologically from their spontaneous counterparts. Even a low radiation dose at the field margins can induce a soft tissue sarcoma.


Assuntos
Dermatofibrossarcoma/etiologia , Neoplasias Induzidas por Radiação , Neoplasias Cutâneas/etiologia , Dermatofibrossarcoma/patologia , Glote , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/patologia , Neoplasias de Células Escamosas/radioterapia , Neoplasias de Células Escamosas/secundário , Radioterapia/efeitos adversos , Neoplasias Cutâneas/patologia
14.
Clin Exp Obstet Gynecol ; 21(1): 24-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8020172

RESUMO

Serum transferrin and ceruloplasmin were measured in 27 healthy women as well as in 21 women who received fractionated radiation therapy (RT) after undergoing surgery for cervical or uterine carcinoma. Although no significant difference in the mean values of transferrin was found between the healthy women and the patients before the initiation of RT, a significantly lower concentration of transferrin after the end of RT (p < 0.001) was observed in comparison to that of controls and of patients before RT. On the contrary, a significantly higher serum concentration of ceruloplasmin was found in patients before and after RT compared to that in healthy women (p < 0.001). The observed increase of ceruloplasmin after RT was not found to be significantly different from the mean value before RT. In conclusion serum transferrin is reduced by RT, while ceruloplasmin which is higher in patients before RT shows a tendency for increase following RT.


Assuntos
Ceruloplasmina/metabolismo , Transferrina/metabolismo , Neoplasias do Colo do Útero/sangue , Neoplasias do Colo do Útero/radioterapia , Neoplasias Uterinas/sangue , Neoplasias Uterinas/radioterapia , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/cirurgia , Neoplasias Uterinas/cirurgia
16.
Radiother Oncol ; 21(3): 183-92, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1924854

RESUMO

One hundred and forty nine patients with carcinoma of the tongue or floor of mouth were treated with interstitial irradiation (+/- external beam therapy) using caesium needles or iridium wires between 1970 and 1986. Multivariate analysis showed the main predictors of outcome to be tumour stage, site and histology. Caesium and iridium techniques gave similarly good local control rates of 90% at 5 years for T1 and T2 tumours when used as the standard departmental method. Local failure was shown to have a major impact on the risk of dying from disease and elective neck irradiation (ENI) conferred a favourable benefit on neck control and survival provided the primary site was controlled. Patients less than 40 years of age appeared to have an unfavourable prognosis. Radical irradiation including interstitial techniques gives excellent results in early oral cancer and is the treatment of choice for T2 tumours. We recommend elective neck irradiation in patients at high risk of developing lymph node metastases.


Assuntos
Soalho Bucal/efeitos da radiação , Neoplasias Bucais/radioterapia , Neoplasias da Língua/radioterapia , Radioisótopos de Césio/uso terapêutico , Inglaterra , Humanos , Radioisótopos de Irídio/uso terapêutico , Irradiação Linfática , Metástase Linfática , Soalho Bucal/patologia , Neoplasias Bucais/patologia , Pescoço/efeitos da radiação , Prognóstico , Estudos Retrospectivos , Neoplasias da Língua/patologia
17.
Neuroradiology ; 33(3): 284-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1831886

RESUMO

Two cases of extramedullary hemopoiesis in the lower spinal column are reported. One of them was due to thalassemia major and the other to thalassemia intermedia. CT and MRI studies showed paraspinal and presacral masses respectively which caused nerve root compression. It is concluded that the differential diagnosis of low back pain and radicular or pseudoradicular pain should include extramedullary hemopoiesis.


Assuntos
Dor nas Costas/etiologia , Hematopoese Extramedular , Adulto , Dor nas Costas/diagnóstico por imagem , Feminino , Humanos , Região Lombossacral , Masculino , Radiografia , Coluna Vertebral/patologia , Talassemia/complicações
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