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1.
Strahlenther Onkol ; 190(7): 654-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24589921

RESUMO

PURPOSE: Squamous cell carcinoma of larynx with subglottic extension (sSCC) is a rare location described to carry a poor prognosis. The aim of this study was to analyze outcomes and feasibility of larynx preservation in sSCC patients. PATIENTS AND METHODS: Between 1996 and 2012, 197 patients with sSCC were treated at our institution and included in the analysis. Stage III-IV tumors accounted for 76%. Patients received surgery (62%), radiotherapy (RT) (18%), or induction chemotherapy (CT) (20%) as front-line therapy. RESULTS: The 5-year actuarial overall survival (OS), locoregional control (LRC), and distant control rate were 59% (95% CI 51-68), 83% (95% CI 77-89), and 88% (95% CI 83-93), respectively, with a median follow-up of 54.4 months. There was no difference in OS and LRC according to front-line treatments or between primary subglottic cancer and glottosupraglottic cancers with subglottic extension. In the multivariate analysis, age > 60 years and positive N stage were the only predictors for OS (HR 2, 95% CI 1.2-3.6; HR1.9, 95% CI 1-3.5, respectively). A lower LRC was observed for T3 patients receiving a larynx preservation protocol as compared with those receiving a front-line surgery (HR 14.1, 95% CI 2.5-136.7; p = 0.02); however, no difference of ultimate LRC was observed according to the first therapy when including T3 patients who underwent salvage laryngectomy (p = 0.6). In patients receiving a larynx preservation protocol, the 5-year larynx-preservation rate was 55% (95% CI 43-68), with 36% in T3 patients. The 5-year larynx preservation rate was 81% (95% CI 65-96) and 35% (95% CI 20-51) for patients who received RT or induction CT as a front-line treatment, respectively. CONCLUSION: Outcomes of sSCC are comparable with other laryngeal cancers when managed with modern therapeutic options. Larynx-preservation protocols could be a suitable option in T1-T2 (RT or chemo-RT) and selected T3 sSCC patients (induction CT).


Assuntos
Carcinoma de Células Escamosas/radioterapia , Glote/efeitos da radiação , Neoplasias Laríngeas/radioterapia , Tratamentos com Preservação do Órgão/estatística & dados numéricos , Órgãos em Risco/efeitos da radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Feminino , França/epidemiologia , Humanos , Neoplasias Laríngeas/mortalidade , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Prevalência , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
2.
Cancer Radiother ; 18(1): 1-6, 2014 Jan.
Artigo em Francês | MEDLINE | ID: mdl-24309002

RESUMO

BACKGROUND: Squamous cell carcinoma of larynx with subglottic extension is a rare location described to carry a poor prognosis. The aim of this study was to analyze outcomes and feasibility of definitive radiotherapy in patients with squamous cell carcinoma. PATIENTS AND METHODS: Between 1998 and 2012, 56 patients with squamous cell carcinoma were treated at our institution and included in the analysis. Patients received definitive radiotherapy/chemoradiotherapy alone (63%) or after induction chemotherapy (37%) at our institute. RESULTS: The 5-year actuarial overall survival, progression-free survival and specific survival were 64% (CI 95%: 48-90), 45% (CI 95%: 28-61), 88% (CI 95%: 78-98), respectively, with median follow-up of 74 months. The 5-year locoregional control was 69% (CI 95%: 56-83) and the 5-year distant control was 95% (CI 95%: 89-100). There was no difference in overall survival and locoregional control according to front-line treatments or between primary subglottic cancer and glotto-supraglottic cancers with subglottic extension. In the multivariate analysis, performance status of at least 1 and positive N stage were the only predictors for overall survival (hazard ratio [HR] [CI 95%]: 6.5 [1.3-34; P=0.03] and 11 [1.6-75; P=0.02], respectively). No difference of locoregional control was observed according to the first received therapy. The univariate analysis retrieved that T3-T4 patients had a lower locoregional control (HR: 3.1; CI 95%: 1.1-9.2, P=0.04), but no prognostic factor was retrieved in the multivariate analysis. In patients receiving a larynx preservation protocol, 5-year larynx preservation rate was 88% (CI 95%: 78-98), and 58% in T3 patients. The 5-year larynx preservation rate was 91% (CI 95%: 79-100) and 83% (CI 95%: 66-100) for patients who received radiotherapy/chemoradiotherapy or induction chemotherapy as a front-line treatment, respectively. CONCLUSION: This analysis suggests that the results for squamous cell carcinoma patients treated with radiotherapy/chemoradiotherapy are comparable to those obtained for other laryngeal tumors. This thus suggests the feasibility of laryngeal preservation protocols for infringement subglottic for selected cases. Further studies are needed to clarify these preliminary data.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Laríngeas/radioterapia , Radioterapia Conformacional , Adulto , Idoso , Idoso de 80 Anos ou mais , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/cirurgia , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Cetuximab , Quimiorradioterapia , Cisplatino/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Neoplasias Laríngeas/complicações , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/terapia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento
3.
Oral Oncol ; 49(8): 830-4, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23747132

RESUMO

PURPOSE/OBJECTIVES: To analyze the clinical features, treatment modalities and outcome of patients treated for a localized esthesioneuroblastoma (ENB). MATERIALS AND METHODS: Forty-three consecutive patients with biopsy proven ENB treated at two referral cancer centers between 1998 and 2010 were retrospectively reviewed. RESULTS: Overall, 5 patients had stage A disease, 13 stage B, 16 stage C and 9 stage D according to the modified Kadish classification. Neo-adjuvant chemotherapy was performed in 23 patients leading to a 74 % response rate. Thirty-one patients were treated by surgery. Thirty-nine patients (90.6%) underwent radiation therapy. Twelve patients received bilateral cervical lymph node irradiation (LNI). After a median follow-up of 77 months, the 5-year overall and progression free survival were 65% and 57%. Twelve patients (28%) had a locoregional relapse leading to 10 ENB-related deaths. The major prognostic factor was the modified Kadish stage with a 3-year survival for stage A-B, C and D of 100%, 48% and 22% respectively (p < 0.0001). Two (9%) isolated cervical lymph node relapses occurred among staged B and C patients treated without elective LNI and none after elective or adjuvant LNI. CONCLUSION: The high risk of locoregional failure in ENB justifies the use of multimodal therapy. Induction chemotherapy leads to a high response rate. Elective LNI might prevent regional failure in locally advanced disease.


Assuntos
Estesioneuroblastoma Olfatório/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estesioneuroblastoma Olfatório/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
4.
Eur Ann Otorhinolaryngol Head Neck Dis ; 128(5): 241-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21798842

RESUMO

Intensity-modulated radiation therapy (IMRT) is an evolution of 3D conformal radiation therapy, which is the current standard radiation therapy technique in head-and-neck cancer. Modulating the radiation intensity of each beam by dynamic interposition of the computer-assisted collimator leaves yields dose distributions that are particularly well adapted to head-and-neck tumor volumes. It is thus possible to predetermine dose per element: i.e., the minimum effective dose to be delivered to tumor areas, and the maximum to be safely delivered to organs at risk. The technique thereby enables complex tumoral targets to be optimally covered, while sparing healthy tissue, and salivary glands in particular. In addition, the technique allows dose-escalation, with a higher dose per session delivered to the macroscopic tumor than to other irradiated areas. The first results of ongoing randomized trials confirmed those of earlier comparative studies, showing marked improvement in side effects, including post-radiation xerostomia. Although the positive impact of this technique on tumor control remains to be proven, salivary function conservation currently makes IMRT the standard treatment in most head-and-neck cancer.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia Adjuvante
5.
Bull Cancer ; 88(8): 793-803, 2001 Aug.
Artigo em Francês | MEDLINE | ID: mdl-11578947

RESUMO

In 1999, the Claudius-Regaud Institute of Toulouse, France, specialized in oncology, set up a workshop in order to assess the quality of its patients medical records. A retrospective evaluation was performed on a 100-chart-sample drawn from all the charts in the institution. Results show that the medical records are subdivised into three parts: medical care, nursing care and imaging. Some of the explored charts show a lack of data, and a certain inconsistency in the charts' organization and in the structure of information was reported. Patient's record is a key to communication between the different care providers in oncology. To improve its quality, efforts will have to be done in restructuring the charts, creating guidelines and training the different caregivers.


Assuntos
Institutos de Câncer/normas , Prontuários Médicos/normas , Controle de Qualidade , França , Humanos , Estudos Retrospectivos
6.
Int J Radiat Oncol Biol Phys ; 47(1): 165-9, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10758319

RESUMO

PURPOSE: Conservative treatment of soft tissue sarcomas most often implies combination of surgical resection and irradiation. The aim of this study was to evaluate low-dose-rate intraoperative brachytherapy, delivered as a boost, in the local control of primary tumors, with special concern about treatment complications. METHODS AND MATERIALS: Between 1986 and 1995, 112 patients underwent intraoperative implant. This report focuses on the group of 58 patients with primary sarcomas treated by combination of conservative surgery, intraoperative brachytherapy, and external irradiation. Most of the tumors were located in the lower limbs (46/58-79%). Median size of the tumor was 10 cm, most of the lesions being T2-T3 (51/58-88%), Grade 2 or 3 (48/58-83%). The mean brachytherapy dose was 20 Gy and external beam irradiation dose 45 Gy. In 36/58 cases, iridium wires had to be placed on contact with neurovascular structures. RESULTS: With a median follow-up of 54 months, the 5-year actuarial survival was 64.9%, with a 5-year actuarial local control of 89%. Of the 6 patients with local relapse, 3 were salvaged. Acute side effects, essentially wound healing problems, occurred in 20/58 patients, late side effects in 16/58 patients (7 neuropathies G2 to G4). No amputation was required. The only significant factor correlated with early side effects was the location of the tumor in the lower limb (p = 0.003), and with late side effects the vicinity of the tumor with neurovascular structures (p = 0.009). CONCLUSION: Brachytherapy allows early delivery of a boost dose in a reduced volume of tissue, precisely mapped by the intraoperative procedure. Combined with external beam irradiation, it is a safe and efficient treatment technique leading to high local control rates and limited functional impairment.


Assuntos
Braquiterapia , Sarcoma/radioterapia , Sarcoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Seguimentos , Humanos , Período Intraoperatório , Radioisótopos de Irídio/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Sarcoma/patologia , Análise de Sobrevida
7.
Arch Intern Med ; 159(22): 2713-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10597762

RESUMO

BACKGROUND: The thyroid gland is among the most radiosensitive organs. However, little is known about the long-term risk of developing a thyroid tumor after fractionated external radiotherapy for cancer during childhood. OBJECTIVE: To study the long-term risk of developing a thyroid tumor in 4096 three-year survivors of childhood cancer treated between May 1942 and December 1985 in 8 centers in France and the United Kingdom, 2827 of whom had received external radiotherapy. METHODS: A wide range of radiation doses were given to the thyroid: 1164 children received less than 0.5 Gy and 812 received more than 5.0 Gy, the average dose being 7.0 Gy. RESULTS: After mean follow-up of 15 years (range, 3-45 years), 14 patients-all of whom had received radiotherapy-developed a clinical thyroid carcinoma. Within the cohort, the relation between radiation dose to the thyroid and risk of thyroid carcinoma and adenoma was similar to that observed in patients who received radiotherapy during childhood for other reasons, such as an excess relative risk per gray of 4 to 8, up to a few gray. In contrast, compared with thyroid cancer incidence in the general population, the standardized incidence of thyroid carcinoma was much higher than expected from the dose-response relationship estimated within the cohort and from patients who received radiotherapy during childhood for other reasons: a dose of 0.5 Gy was associated with a standardized incidence ratio of 35 (90% confidence interval, 10-87) and a dose of 3.6 Gy with a standardized incidence ratio of 73 (90% confidence interval, 28-153). We did not show a reduction in excess relative risk per gray with use of an increasing number of fractions. CONCLUSION: Although we cannot estimate the exact proportion, it is probable that some or all children who are treated for cancer are predisposed to developing a thyroid carcinoma.


Assuntos
Neoplasias Induzidas por Radiação/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Adenoma/epidemiologia , Adenoma/etiologia , Adolescente , Adulto , Carcinoma/epidemiologia , Carcinoma/etiologia , Criança , Estudos de Coortes , Feminino , Seguimentos , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/epidemiologia , Fatores de Tempo , Reino Unido/epidemiologia
8.
Radiat Res ; 152(4): 404-11, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10477917

RESUMO

In this paper, we describe the effect of the inhibitor of farnesyltransferase (FTI-277) on radioresistance induced by the 24-kDa isoform of FGF2 in human cells expressing wild-type RAS. Treatment with FTI-277 (20 microM) for 48 h prior to irradiation led to a significant decrease in survival of radioresistant cells expressing the 24-kDa isoform (HeLa 3A) but had no effect on the survival of control cells (HeLa PINA). The radiosensitizing effect of FTI-277 is accompanied by a stimulation of postmitotic cell death in HeLa 3A cells and by a reduction in G(2)/M-phase arrest in both cell types. These results clearly demonstrate that at least one farnesylated protein is involved in the regulation of the radioresistance induced by the 24-kDa isoform of FGF2. Furthermore, the radiation-induced G(2)/M-phase arrest is also under the control of farnesylated protein. This work also demonstrates that FTase inhibitors may be effective radiosensitizers of certain human tumors with wild-type RAS.


Assuntos
Alquil e Aril Transferases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Metionina/análogos & derivados , Tolerância a Radiação/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Farnesiltranstransferase , Células HeLa , Humanos , Metionina/farmacologia
9.
Radiother Oncol ; 50(2): 191-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10368043

RESUMO

PURPOSE: To measure the incidence of second non-germ cell malignancies (SNGCM) in patients treated for a stage I-II testicular seminoma. MATERIALS AND METHODS: From 1970 to 1992, 131 evaluable patients received in the Institut Claudius Regaud a post-orchiectomy treatment for a stage I-II testicular seminoma. The therapeutic modalities, including salvage treatment for six recurrences, were as follows: infradiaphragmatic radiotherapy (IDRT) (n = 55); infra- and supradiaphragmatic radiotherapy (IDRT + SDRT) (n = 64); IDRT + SDRT with chemotherapy (n = 12). The mean follow-up was 11 years. The cumulative incidence of SNGCM was compared to the overall cancer incidence in the general male population on the basis of the Tarn Cancer Registry; the relative risk was expressed as a standardized incidence ratio (SIR). RESULTS: Overall, the cumulative incidence of SNGCM was 10.7% (14/131 cases). The SIR was equal to 2.81 (95% confidence interval (CI) 1.54-4.72; P < 0.001) and increased with follow-up duration. The SIR was significantly increased in 64 patients treated with IDRT + SDRT (SIR = 3.08; 95% CI 1.47-5.66; P = 0.002) but not in 55 patients treated with IDRT alone (SIR = 0.62; 95% CI 0.01-3.43; P = 0.8). The 12 patients who received chemotherapy had an SIR of 26.2 (95% CI 5.48-77.69; P < 0.001), while the SIR was 2.26 in the 119 patients who did not receive any chemotherapy (95% CI 1.13-4.04; P = 0.01 ). Of four hematologic malignancies, three appeared in the 12 patients who received chemotherapy. CONCLUSIONS: An increased risk of SNGCM after SDRT + IDRT has been demonstrated. After IDRT alone, the risk of second cancer is not incremented after a median follow-up of 6 years, but further observation of the patients is necessary to achieve final conclusions. Our results suggest that the risk of second cancer and especially of hematologic malignancy is increased by the association of chemotherapy and radiation.


Assuntos
Neoplasias Induzidas por Radiação/etiologia , Segunda Neoplasia Primária/etiologia , Seminoma/radioterapia , Neoplasias Testiculares/radioterapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Induzidas por Radiação/patologia , Segunda Neoplasia Primária/patologia , Estudos Retrospectivos , Fatores de Risco , Seminoma/tratamento farmacológico , Seminoma/patologia , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/patologia , Resultado do Tratamento
10.
Int J Radiat Oncol Biol Phys ; 44(1): 47-52, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10219793

RESUMO

PURPOSE: In order to provide more information for the clinician and to analyze the impact of radiation therapy on the loco-regional disease-free interval (LRFI), disease-free interval (DFI) and specific overall survival (OS), a multicentric retrospective study of uterine sarcomas has been undertaken using cases reported to the Grup Oncològic Català-Occità (GOCO). PATIENTS AND METHODS: One hundred three patients were selected for this study with a median follow-up period of 49 months. Patients were restaged using the FIGO classification for endometrial adenocarcinoma. Radiotherapy was administered postoperatively to the entire pelvis in 52% of cases (54/103) and was combined with brachytherapy in 24 patients. Mean given dose was 48 Gy, with a 95% confidence interval of 45 to 50 Gy. Variables have been tested for homogeneity between hospitals. Univariate and multivariate analyses have also been carried out. RESULTS: Mean age of the selected patients was 59 years (range 35-84). Stages were distributed as follows: 66 patients (64%) in Stage I; 16 in Stage II (15.5%); 12 in Stage III (11.5%); 9 patients in Stage IVa (9%). Pathological distribution was 41.5% leiomyosarcoma, 39% mixed Mullerian tumours, 16.5% stromal sarcomas, and 2.9% of a miscellaneous group. Overall survival for the entire group was 63.7% and 56% at 2 and 5 years, respectively. Probability of LRFI reached 59.8% at 2 years and 57.4 at 5 years. The DFI at 2 and 5 years were 52.9 % and 48.7%, respectively. The LRFI probability was 41% and 36% at 2 and 5 years, respectively, without radiotherapy and reached 76% at 2 and 5 years among those patients treated with radiotherapy. There was also an increase in DFI probability because of the effect of radiotherapy, from 35% to 68.5% and from 33% to 53% at 2 and 5 years, respectively. The overall survival probability for patients treated with radiotherapy was 76% and 73% at 2 and 5 years, respectively and 51% at 2 years and 37% at 5 years without radiotherapy. Multivariate analysis demonstrated that radiotherapy improved LRFI, DFI, and overall survival. CONCLUSION: We conclude that postoperative radiotherapy in our series of patients diagnosed with uterine sarcoma has an impact on loco-regional and disease-free progression intervals and survival.


Assuntos
Tumor Mulleriano Misto/radioterapia , Sarcoma/radioterapia , Neoplasias Uterinas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Intervalo Livre de Doença , Feminino , Humanos , Leiomiossarcoma/patologia , Leiomiossarcoma/radioterapia , Pessoa de Meia-Idade , Tumor Mulleriano Misto/patologia , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Recidiva , Estudos Retrospectivos , Sarcoma/patologia , Neoplasias Uterinas/patologia
11.
Br J Cancer ; 79(11-12): 1884-93, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10206309

RESUMO

The variation in the risk of solid second malignant neoplasms (SMN) with time since first cancer during childhood has been previously reported. However, no study has been performed that controls for the distribution of radiation dose and the aggressiveness of past chemotherapy, which could be responsible for the observed temporal variation of the risk. The purpose of this study was to investigate the influence of the treatment on the long-term pattern of the incidence of solid SMN after a first cancer in childhood. We studied a cohort of 4400 patients from eight centres in France and the UK. Patients had to be alive 3 years or more after a first cancer treated before the age of 17 years and before the end of 1985. For each patient in the cohort, the complete clinical, chemotherapy and radiotherapy history was recorded. For each patient who had received external radiotherapy, the dose of radiation received by 151 sites of the body were estimated. After a mean follow-up of 15 years, 113 children developed a solid SMN, compared to 12.3 expected from general population rates. A similar distribution pattern was observed among the 1045 patients treated with radiotherapy alone and the 2064 patients treated with radiotherapy plus chemotherapy; the relative risk, but not the excess absolute risk, of solid SMN decreased with time after first treatment; the excess absolute risk increased during a period of at least 30 years after the first cancer. This pattern remained after controlling for chemotherapy and for the average dose of radiation to the major sites of SMN. It also remained when excluding patients with a first cancer type or an associated syndrome known to predispose to SMN. When compared with radiotherapy alone, the addition of chemotherapy increases the risk of solid SMN after a first cancer in childhood, but does not significantly modify the variation of this risk during the time after the first cancer.


Assuntos
Segunda Neoplasia Primária/terapia , Idade de Início , Antineoplásicos/uso terapêutico , Criança , Pré-Escolar , Relação Dose-Resposta à Radiação , Seguimentos , França/epidemiologia , Humanos , Incidência , Lactente , Segunda Neoplasia Primária/epidemiologia , Fatores de Risco , Fatores de Tempo , Reino Unido/epidemiologia
13.
Cancer Radiother ; 2(2): 160-7, 1998.
Artigo em Francês | MEDLINE | ID: mdl-9749110

RESUMO

The development of non-invasive head fixation systems, allowing 3D determination of the target coordinates, has lead to the increased use of fractionated stereotactic irradiation. These systems have been checked for accuracy and the mean precision of repositioning has been evaluated to +/- 1 mm. With the mean geometrical accuracy set at +/- 1 mm, a 2 mm safety margin is usually added to the clinical target volume in order to define the planning target volume. Quality assurance procedures must conform to the required precision of the technique while remaining realistic in day-to-day use relative to planned conventional treatments. Biologically different from single dose irradiation, the fractionated stereotactic irradiation completes the range of techniques used in the treatment of intra-cerebral lesions.


Assuntos
Fracionamento da Dose de Radiação , Radiocirurgia/métodos , Restrição Física/métodos , Desenho de Equipamento , Humanos , Controle de Qualidade , Radiocirurgia/instrumentação , Radiocirurgia/tendências , Restrição Física/instrumentação
15.
Int J Cancer ; 77(3): 370-7, 1998 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-9663598

RESUMO

Osteosarcoma is the most frequent second primary cancer occurring during the first 20 years following treatment for a solid cancer in childhood. Using a cohort study of children treated for a solid cancer, we investigated the incidence and etiology of osteosarcoma as a second malignant neoplasm after childhood cancer in a cohort and a case-control study. We analysed the relationship between the local dose of radiation and the risk of osteosarcoma, taking into account chemotherapy received. A cohort study of 4,400 3-year survivors of a first solid cancer during childhood diagnosed in France or the United Kingdom, between 1942 and 1986, revealed 32 subsequent osteosarcomas. In a nested case-control study, we matched 32 cases and 160 controls for sex, type of first cancer, age at first cancer and the duration of follow-up. Parameters studied were the incidence of osteosarcoma, the cumulative local dose of irradiation and the cumulative dose of chemotherapy received by cases and controls. The risk of a osteosarcoma was found to be a linear function of the local dose of radiation (excess relative risk per gray=1.8), and was found to increase with the number of moles of electrophilic agents per square meter but not with other drugs. No interaction was noted between radiotherapy and chemotherapy. Bilateral retinoblastoma, Ewing's sarcoma and soft tissue sarcoma were found to render patients susceptible to a higher risk of developing an osteosarcoma as a second malignant neoplasm. We recommend long-term surveillance of patients who were treated during childhood for bilateral retinoblastoma, Ewing's sarcoma, soft tissue sarcoma, as well as other first cancer treated with radiotherapy plus high doses of chemotherapy, without focusing exclusively on the radiation field.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias Ósseas/epidemiologia , Neoplasias Induzidas por Radiação/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Osteossarcoma/epidemiologia , Radioterapia/efeitos adversos , Adolescente , Adulto , Neoplasias Ósseas/induzido quimicamente , Neoplasias Ósseas/etiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , França/epidemiologia , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/etiologia , Segunda Neoplasia Primária/induzido quimicamente , Segunda Neoplasia Primária/etiologia , Razão de Chances , Osteossarcoma/induzido quimicamente , Osteossarcoma/etiologia , Fatores de Risco , Fatores de Tempo , Reino Unido/epidemiologia
16.
Int J Radiat Oncol Biol Phys ; 41(1): 123-6, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9588926

RESUMO

PURPOSE: To determine the effect of low-dose splenic irradiation on severe Zidovudine-resistant, HIV-1-associated thrombocytopenia (HAT). METHODS AND MATERIALS: Between September 1994 and October 1996, 17 patients were included in a prospective study. The patients met the following criteria for inclusion: hemorrhagic symptoms or a platelet count below or equal to 50 x 10(9)/l and normal numbers of megakaryocytes on bone aspiration. The mean baseline platelet count was 20.3 (+/- 14.4) x 10(9)/l; four patients had a platelet count inferior to 10 x 10(9)/l. Splenic volume was defined by ultrasonography. A total dose of 9 Gy was given using an isocentric parallel pair field technique. RESULTS: One month after the end of treatment six patients had a significant rise in their platelet count. Clinically, hemorrhagic symptoms stopped for all patients that were symptomatic. Unfortunately, duration of response was short because for one patient only the platelet count remains stable with a follow-up of 6 months. All patients are alive and in recent evaluation, with four out of eight patients receiving a combination of antiretroviral therapy had a platelet count above 50 x 10(9)/l. CONCLUSION: Our results are disappointing concerning the duration of response, especially comparatively to those reported in autoimmune thrombocytopenia. Mechanisms of HAT are more complex, and megakaryocytes' infection may play an important role. Splenic irradiation should be considered as palliative treatment for the minority of patients with severe bleeding that does not respond to standard medical treatment.


Assuntos
Doenças Autoimunes/radioterapia , Infecções por HIV/complicações , Baço/efeitos da radiação , Trombocitopenia/radioterapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Dosagem Radioterapêutica , Falha de Tratamento
17.
Cancer Res ; 57(7): 1364-70, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9102225

RESUMO

The basic fibroblast growth factor-(bFGF) mediated signal transduction pathway has been implicated in cellular resistance to ionizing radiation. bFGF is synthesized from the same mRNA in four isoforms resulting from alternative initiations of translation at three CUG start codons (24, 21.5, and 21 kDa) and one AUG start codon (18 kDa). We analyzed the implication of high- and low-molecular forms of bFGF in radioresistance acquisition. For this, we transfected HeLa cells with retroviral vector containing either the CUG-initiated 24-kDa molecular form (HeLa 3A cells), the AUG-initiated 18-kDa molecular bFGF form (HeLa 5A cells), or the vector alone (HeLa PINA cells). A significantly increased radioresistance was obtained only in HeLa 3A cells (Dq = 810 +/- 24 cGy) compared with wild-type cells (Dq = 253 +/- 49 cGy) or HeLa PINA cells (Dq = 256 +/- 29 cGy; P < 0.001). This radioprotective effect was independent of an inhibition of radiation-induced apoptosis but related to an increased G2 duration after irradiation and to an hyperphosphorylation of p34cdc2 kinase. Knowledge of the high-molecular bFGF form-induced radioresistance pathway could offer novel targets for decreasing the radioresistance phenotype of tumors expressing high amounts of bFGF, such as glioblastoma.


Assuntos
Proteína Quinase CDC2/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fase G2/efeitos da radiação , Tolerância a Radiação/fisiologia , Protetores contra Radiação/farmacologia , Tirfostinas , Apoptose/efeitos da radiação , Western Blotting , Catecóis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Inibidores Enzimáticos/farmacologia , Fase G2/fisiologia , Células HeLa , Humanos , Nitrilas/farmacologia , Fosforilação/efeitos da radiação , Proteínas Tirosina Quinases/antagonistas & inibidores
18.
Radiat Res ; 147(3): 277-83, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9052672

RESUMO

Duration of the G2-phase delay and arrest after exposure to ionizing radiation is thought to influence radiosensitivity. The kinase activity of the p34cdc2-cyclin B complex and the p34cdc2-cyclin A complex is implicated in G2- to M-phase transition and in G2-phase arrest after exposure to ionizing radiation. We analyzed the expression level and the subcellular location of p34cdc2, cyclin A and cyclin B in head and neck squamous cell carcinoma (SCC) tumors; samples were obtained from patients with locally nonrecurrent and recurrent tumors that had been treated by surgery and radiotherapy. No significant difference was noticed in cyclin A, cyclin B and p34cdc2 expression. However, we noted a significant preferential cytoplasmic location of p34cdc2 in recurring tumors compared to the nonrecurring ones (P < 0.001). This abnormal location of p34cdc2 occurs even in primary tumors in patients with recurring tumors, suggesting that a default in the activation of p34cdc2 kinase could be implicated in clinical radioresistance.


Assuntos
Proteína Quinase CDC2/metabolismo , Carcinoma de Células Escamosas/metabolismo , Citoplasma/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/ultraestrutura , Ciclinas/metabolismo , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/ultraestrutura , Humanos , Técnicas Imunoenzimáticas , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/ultraestrutura
19.
Am J Clin Oncol ; 20(1): 1-5, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9020278

RESUMO

A phase I-II study was initiated in February 1991 of concomitant radiation and cisplatin (CDDP) in the treatment of unresectable head and neck squamous cell carcinomas (n = 12). The first patient was treated palliatively for a cervical recurrence of laryngeal cancer. The 11 other patients had locally advanced (stage IV) previously untreated carcinomas of the oropharynx (n = 9), hypopharynx (n = 1), or cervical node with unknown primary site (n = 1). Standard external radiation was carried out up to a total dose of 60 Gy/6 weeks (7 MeV electron beam) for the first patient and 72 Gy/8 weeks (Co60 beam) for the other 11 patients. CDDP was infused continuously during the entire radiation treatment, 5 days/week. The starting dose was 4 mg/m2/day and was escalated by increments of 1 mg/m2/day; dose-limiting toxicity was observed at 7 mg/m2/day. Neutropenia (grade 4, one patient; grade 3, three patients) and thrombocytopenia (grade 3, one patient; grade 2, one patient) were the limiting factors. Therefore, the recommended dose of CDDP is 6 mg/m2/day. All patients but one completed the scheduled radiation. For the entire group, mucositis was not more severe than that observed with radiotherapy alone. There was no nephro-, oto-, or neurotoxicity. A complete response was obtained in eight (66%) patients. Of these, four were free of disease 12-34 months after completion of treatment and one had a total glossectomy for a tongue necrosis. For the whole series, the mean overall survival was 16 months posttreatment. Pharmacokinetic analysis indicated the total cisplatin accumulation at the end of treatment to be 743-1551 ng/ml. Accumulation of ultrafilterable platin was noted in only one patient (137 ng/ml at the end of treatment).


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/terapia , Cisplatino/uso terapêutico , Neoplasias de Cabeça e Pescoço/terapia , Radiossensibilizantes/uso terapêutico , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Cisplatino/administração & dosagem , Cisplatino/farmacocinética , Terapia Combinada , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiossensibilizantes/administração & dosagem , Radiossensibilizantes/farmacocinética , Dosagem Radioterapêutica , Indução de Remissão , Análise de Sobrevida
20.
Cancer Radiother ; 1(6): 836-47, 1997.
Artigo em Francês | MEDLINE | ID: mdl-9614903

RESUMO

At the present time, the current improvement of technical and dosimetric aspects of radiation oncology has to be evaluated in terms of potential benefit for the patient and the society. For this last point of view, specially designed economic analyses must be performed in order to justify the number of resources involved by these technical improvements. If the question is how the current technical procedures could reduce the risk of undesirable side-effects, the response cannot be immediately drawn from the literature. This paper emphasizes the possibility to evaluate the role of side-effects as endpoints of economic analyses when using special models in medical decision making such as Markov's. Only few oncologic situations are reliable to properly analyze the relationship between sophisticated radiation techniques and the incidence of post-radiation complications. These situations should be selected when prospective economic analyses are planned in the field of radiation therapy.


Assuntos
Lesões por Radiação/economia , Radioterapia , Custos e Análise de Custo , Estudos de Avaliação como Assunto , Custos de Cuidados de Saúde , Humanos , Neoplasias/economia , Neoplasias/mortalidade , Neoplasias/radioterapia , Lesões por Radiação/terapia , Radioterapia/efeitos adversos , Radioterapia/economia , Falha de Tratamento
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