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BACKGROUND: In patients with non-small-cell lung cancer (NSCLC), the use of postoperative radiotherapy (PORT) has been controversial since 1998, because of one meta-analysis showing a deleterious effect on survival in patients with pN0 and pN1, but with an unclear effect in patients with pN2 NSCLC. Because many changes have occurred in the management of patients with NSCLC, the role of three-dimensional (3D) conformal PORT warrants further investigation in patients with stage IIIAN2 NSCLC. The aim of this study was to establish whether PORT should be part of their standard treatment. METHODS: Lung ART is an open-label, randomised, phase 3, superiority trial comparing mediastinal PORT to no PORT in patients with NSCLC with complete resection, nodal exploration, and cytologically or histologically proven N2 involvement. Previous neoadjuvant or adjuvant chemotherapy was allowed. Patients aged 18 years or older, with an WHO performance status of 0-2, were recruited from 64 hospitals and cancer centres in five countries (France, UK, Germany, Switzerland, and Belgium). Patients were randomly assigned (1:1) to either the PORT or no PORT (control) groups via a web randomisation system, and minimisation factors were the institution, administration of chemotherapy, number of mediastinal lymph node stations involved, histology, and use of pre-treatment PET scan. Patients received PORT at a dose of 54 Gy in 27 or 30 daily fractions, on five consecutive days a week. Three dimensional conformal radiotherapy was mandatory, and intensity-modulated radiotherapy was permitted in centres with expertise. The primary endpoint was disease-free survival, analysed by intention to treat at 3 years; patients from the PORT group who did not receive radiotherapy and patients from the control group with no follow-up were excluded from the safety analyses. This trial is now closed. This trial is registered with ClinicalTrials.gov number, NCT00410683. FINDINGS: Between Aug 7, 2007, and July 17, 2018, 501 patients, predominantly staged with 18F-fluorodeoxyglucose (18F-FDG) PET (456 [91%]; 232 (92%) in the PORT group and 224 (90%) in the control group), were enrolled and randomly assigned to receive PORT (252 patients) or no PORT (249 patients). At the cutoff date of May 31, 2019, median follow-up was 4·8 years (IQR 2·9-7·0). 3-year disease-free survival was 47% (95% CI 40-54) with PORT versus 44% (37-51) without PORT, and the median disease-free survival was 30·5 months (95% CI 24-49) in the PORT group and 22·8 months (17-37) in the control group (hazard ratio 0·86; 95% CI 0·68-1·08; p=0·18). The most common grade 3-4 adverse events were pneumonitis (13 [5%] of 241 patients in the PORT group vs one [<1%] of 246 in the control group), lymphopenia (nine [4%] vs 0), and fatigue (six [3%] vs one [<1%]). Late-grade 3-4 cardiopulmonary toxicity was reported in 26 patients (11%) in the PORT group versus 12 (5%) in the control group. Two patients died from pneumonitis, partly related to radiotherapy and infection, and one patient died due to chemotherapy toxicity (sepsis) that was deemed to be treatment-related, all of whom were in the PORT group. INTERPRETATION: Lung ART evaluated 3D conformal PORT after complete resection in patients who predominantly had been staged using (18F-FDG PET-CT and received neoadjuvant or adjuvant chemotherapy. 3-year disease-free survival was higher than expected in both groups, but PORT was not associated with an increased disease-free survival compared with no PORT. Conformal PORT cannot be recommended as the standard of care in patients with stage IIIAN2 NSCLC. FUNDING: French National Cancer Institute, Programme Hospitalier de Recherche Clinique from the French Health Ministry, Gustave Roussy, Cancer Research UK, Swiss State Secretary for Education, Research, and Innovation, Swiss Cancer Research Foundation, Swiss Cancer League.
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Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Idoso , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Mediastino/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia de Intensidade ModuladaRESUMO
BACKGROUND: Often curative treatment for locally advanced resectable esophageal or gastro-esophageal junctional cancer consists of concurrent neoadjuvant radiotherapy and chemotherapy followed by surgery. Currently, one of the most commonly used chemotherapy regimens in this setting is a combination of a fluoropyrimidin and of a platinum analogue. Due to the promising results of the recent CROSS trial, another regimen combining paclitaxel and carboplatin is also widely used by European and American centers. No clinical study has shown the superiority of one treatment over the other. The objective of this Phase II study is to clarify clinical practice by comparing these two chemotherapy treatments. Our aim is to evaluate, in operable esophageal and gastro-esophageal junctional cancer, the complete resection rate and severe postoperative morbidity rate associated with these two neoadjuvant chemotherapeutic regimens (carboplatin-paclitaxel or fluorouracil-oxaliplatin-folinic acid) when each is combined with the radiation regime utilized in the CROSS trial. METHODS/DESIGN: PROTECT is a prospective, randomized, multicenter, open arms, phase II trial. Eligible patients will have a histologically confirmed adenocarcinoma or squamous cell carcinoma and be treated with neoadjuvant radiochemotherapy followed by surgery for stage IIB or stage III resectable esophageal cancer. A total of 106 patients will be randomized to receive either 3 cycles of FOLFOX combined to concurrent radiotherapy (41.4 Grays) or carboplatin and paclitaxel with the same radiation regimen, using a 1:1 allocation ratio. DISCUSSION: This ongoing trial offers the unique opportunity to compare two standards of chemotherapy delivered with a common regimen of preoperative radiation, in the setting of operable locally advanced esophageal or gastro-esophageal junctional tumors. TRIAL REGISTRATION: NCT02359968 (ClinicalTrials.gov) (registration date: 9 FEB 2015), EudraCT: 2014-000649-62 (registration date: 10 FEB 2014).
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/cirurgia , Quimiorradioterapia , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Fracionamento da Dose de Radiação , Neoplasias Esofágicas/cirurgia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVES: To characterise the motion of pulmonary tumours during stereotactic body radiation therapy (SBRT) and to evaluate different margins when creating the planning target volume (PTV) on a single 4D CT scan (4DCT). METHODS: We conducted a retrospective single-site analysis on 30 patients undergoing lung SBRT. Two 4DCTs (4DCT1 and 4DCT2) were performed on all patients. First, motion was recorded for each 4DCT in anterior-posterior (AP), superior-inferior (SI) and rightleft (RL) directions. Then, we used 3 different margins (3,4 and 5 mm) to create the PTV, from the internal target volume (ITV) of 4DCT1 only (PTV D1 + 3, PTV D1 + 4, PTV D1 + 5). We compared, using the Dice coefficient, the volumes of these 3 PTVs, to the PTV actually used for the treatment (PTVttt). Finally, new treatment plans were calculated using only these 3 PTVs. We studied the ratio of the D2%, D50% and D98% between each new plan and the plan actually used for the treatment (D2% PTVttt, D50% PTVttt, D50% ITVttt D98% PTVttt). RESULTS: 30 lesions were studied. The greatest motion was observed in the SI axis (8.8 ± 6.6 [0.4-25.8] mm). The Dice index was higher when comparing PTVttt to PTV D1 + 4 mm (0.89 ± 0.04 [0.82-0.98]). Large differences were observed when comparing plans relative to PTVttt and PTV D1 + 3 for D98% PTVttt (0.85 ± 0.24 [0.19-1.00]). and also for D98% ITVttt (0.93 ± 0.12 [0.4-1.0]).D98% PTVttt (0.85 ± 0.24 [0.19-1.00], p value = 0.003) was statistically different when comparing plans relative to PTVttt and PTV D1 + 3. No stastistically differences were observed when comparing plans relative to PTVttt and PTV D1 + 4. A difference greater than 10% relative to D98% PTVttt was found for only in one UL lesion, located under the carina. CONCLUSION: A single 4DCT appears feasible for upper lobe lesions located above the carina, using a 4-mm margin to generate the PTV. ADVANCE IN KNOWLEDGE: Propostion of a personalized SBRT treatment (number of 4DCT, margins) according to tumor location (above or under the carina).
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Tomografia Computadorizada Quadridimensional , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador , Humanos , Neoplasias Pulmonares/patologia , Estudos RetrospectivosRESUMO
BACKGROUND AND PURPOSE: The Radiation Induced Sarcoma (RIS) is a rare but serious adverse event following radiotherapy (RT). Current RT techniques are more precise, but irradiate a larger volume at a low dose. This study aimed to describe radiation characteristics in a large series of patients suffering from RIS. MATERIALS AND METHODS: Patient-representative voxel-based anthropomorphic phantoms were used to reconstruct patient-specific RT fields for 125 patients diagnosed with RIS after primary breast cancer. For each patient, the location of the RIS onset site was determined and transferred onto the phantom as a contour. Using a treatment planning system (TPS), the dose distribution on the RIS in the phantom was calculated. RESULTS: The mean dose (Dmean) received in the area where RIS subsequently developed was 47.8 ± 11.6 Gy. The median dose in the zones where RIS later developed ranged from 11 Gy to 58.8 Gy. The median time from RT to RIS development was 8 years (range 2-32 years). Analysis for predictors of time to radiation-induced sarcoma development highlighted a significant impact of age of patient during the RT whereas in multivariable analysis chemotherapy and hormonotherapy for primary breast cancer were not associated with a significant difference in time to diagnosis of RIS. CONCLUSIONS: This study highlights that the dose received by the tissue in which the RIS developed was almost 47 Gy. These results are encouraging for the use of new RT techniques increasing volumes receiving low doses, without fear of an excess of RIS over the next 10 years.
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Neoplasias da Mama , Sarcoma , Neoplasias de Tecidos Moles , Mama , Neoplasias da Mama/radioterapia , Feminino , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica , Sarcoma/etiologia , Sarcoma/radioterapiaRESUMO
PURPOSE: To develop easily applicable guidelines for the determination of initially involved lymph nodes to be included in the radiation fields. PATIENTS AND METHODS: Patients with supra-diaphragmatic Hodgkin lymphoma. All the imaging procedures were carried out with patients in the treatment position. The prechemotherapy PET/CT was coregistered with the postchemotherapy CT simulation for planning purposes. Initially involved lymph nodes were determined on fused prechemotherapy CT and FDG-PET imaging data. The initial assessment was verified with the postchemotherapy CT scan. RESULTS: The classic guidelines for determining the involvement of lymph nodes were not easily applicable and did not seem to reflect the exact extent of Hodgkin lymphoma. Three simple steps were used to pinpoint involved lymph nodes. First, FDG-PET scans were meticulously analysed to detect lymph nodes that were overlooked on CT imaging. Second, any morphological and/or functional asymmetry was sought on CT and FDG-PET scans. Third, a decrease in size or the disappearance of initially visible lymph nodes on the prechemotherapy CT scan as compared to the postchemotherapy CT scan was considered as surrogate proof of initial involvement. CONCLUSIONS: All the radiological procedures should be performed on patients in the treatment position for proper coregistration. It is highly advisable that all CT and/or CT/PET scans be performed with IV contrast. Using the above-mentioned three simple guidelines, initially involved lymph nodes can be detected with very satisfactory accuracy. It is also emphasized that the classic guidelines (2, 3, 4) can always be used when deemed necessary.
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Doença de Hodgkin/radioterapia , Irradiação Linfática/métodos , Guias de Prática Clínica como Assunto , Meios de Contraste , Fluordesoxiglucose F18 , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Humanos , Metástase Linfática/diagnóstico por imagem , Compostos Radiofarmacêuticos , Análise de Sobrevida , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
See an invited perspective on this article on page 1043.This multicenter phase II study investigated a selective radiotherapy dose increase to tumor areas with significant 18F-misonidazole (18F-FMISO) uptake in patients with non-small cell lung carcinoma (NSCLC). Methods: Eligible patients had locally advanced NSCLC and no contraindication to concomitant chemoradiotherapy. The 18F-FMISO uptake on PET/CT was assessed by trained experts. If there was no uptake, 66 Gy were delivered. In 18F-FMISO-positive patients, the contours of the hypoxic area were transferred to the radiation oncologist. It was necessary for the radiotherapy dose to be as high as possible while fulfilling dose-limiting constraints for the spinal cord and lungs. The primary endpoint was tumor response (complete response plus partial response) at 3 mo. The secondary endpoints were toxicity, disease-free survival (DFS), and overall survival at 1 y. The target sample size was set to demonstrate a response rate of 40% or more (bilateral α = 0.05, power 1-ß = 0.95). Results: Seventy-nine patients were preincluded, 54 were included, and 34 were 18F-FMISO-positive, 24 of whom received escalated doses of up to 86 Gy. The response rate at 3 mo was 31 of 54 (57%; 95% confidence interval [CI], 43%-71%) using RECIST 1.1 (17/34 responders in the 18F-FMISO-positive group). DFS and overall survival at 1 y were 0.86 (95% CI, 0.77-0.96) and 0.63 (95% CI, 0.49-0.74), respectively. DFS was longer in the 18F-FMISO-negative patients (P = 0.004). The radiotherapy dose was not associated with DFS when adjusting for the 18F-FMISO status. One toxic death (66 Gy) and 1 case of grade 4 pneumonitis (>66 Gy) were reported. Conclusion: Our approach results in a response rate of 40% or more, with acceptable toxicity. 18F-FMISO uptake in NSCLC patients is strongly associated with poor prognosis features that could not be reversed by radiotherapy doses up to 86 Gy.
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Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Fracionamento da Dose de Radiação , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Misonidazol/análogos & derivados , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Feminino , França , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Misonidazol/farmacocinética , Variações Dependentes do Observador , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taxa de Sobrevida , Resultado do Tratamento , Hipóxia Tumoral/efeitos da radiaçãoRESUMO
In completely resected non-small-cell lung cancer (NSCLC) patients with pathologically involved mediastinal lymph nodes (N2), administration of adjuvant platinum-based chemotherapy is now considered the standard of care, based on level 1 evidence. The role of post-operative radiotherapy (PORT) in this group of patients remains controversial. In the PORT meta-analysis published in 1998, the conclusions were that if adjuvant radiotherapy was detrimental to patients with early-stage completely resected NSCLC, the role of PORT in the treatment of tumours with N2 involvement was unclear and further research was warranted. Recent retrospective and non-randomized studies as well as subgroup analyses of recent randomized trials evaluating adjuvant chemotherapy, provide evidence of the possible benefit of PORT in patients with mediastinal nodal involvement. The question of PORT indication is also valid for those patients with proven N2 disease who undergo neo-adjuvant chemotherapy followed by surgery. The risk of local recurrence for N2 patients varies between 20% and 60%. Based on currently available data, PORT should be discussed for fit patients with completely resected NSCLC with N2 nodal involvement, within a multidisciplinary setting, preferably after completion of adjuvant chemotherapy or after surgery if patients have had neo-adjuvant chemotherapy. There is need for new randomized evidence to reassess PORT using modern three-dimensional conformal radiation technique, with attention to normal organ sparing, particularly lung and heart, to reduce the possible additional toxicity. Randomized evidence is needed. A new large international multi-institutional randomized trial Lung ART evaluating PORT in this patient population is now underway, as well as a Chinese study comparing postoperative sequential chemotherapy followed by radiotherapy versus adjuvant chemotherapy alone.
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PURPOSE: To propose an alternative approach for treatment of pulmonary marginal zone lymphoma, using a very small radiation dose (2 × 2 Gy) delivered exclusively to tumor sites. METHODS AND MATERIALS: Patients had localized pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma according to the World Health Organization classification. The 6-MV radiation treatments were delivered using tumor-limited fields, except in cases of diffuse bilateral involvement. Two daily fractions of 2 Gy were delivered to tumor-limited fields using a 6-MV linear accelerator. RESULTS: Ten patients with pulmonary MALT lymphoma entered the study. All but 1 had localized tumor masses. The median follow-up was 56 months (range, 2-103 months). Complete remission or an unconfirmed complete remission was obtained in 60% of patients within the first 2 months, and two additional partial responses were converted into a long-term unconfirmed complete remission. All patients are well and alive, no local progression was observed, and the 5-year progression-free survival rate was 87.5% (95% confidence interval 49%-97%). CONCLUSIONS: Our results suggest that extremely low radiation doses delivered exclusively to tumor sites might be a treatment option in pulmonary MALT lymphoma.
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Neoplasias Pulmonares/radioterapia , Linfoma de Zona Marginal Tipo Células B/radioterapia , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Linfoma de Zona Marginal Tipo Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Indução de Remissão/métodos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
PURPOSE: To assess the additional benefits of using the deep-inspiration breath-hold (DIBH) technique with intensity-modulated radiotherapy (IMRT) in terms of the protection of organs at risk for patients with mediastinal Hodgkin's disease. METHODS AND MATERIALS: Patients with early-stage Hodgkin's lymphoma with mediastinal involvement were entered into the study. Two simulation computed tomography scans were performed for each patient: one using the free-breathing (FB) technique and the other using the DIBH technique with a dedicated spirometer. The clinical target volume, planning target volume (PTV), and organs at risk were determined on both computed tomography scans according to the guidelines of the European Organization for Research and Treatment of Cancer. In both cases, 30 Gy in 15 fractions was prescribed. The dosimetric parameters retrieved for the statistical analysis were PTV coverage, mean heart dose, mean coronary artery dose, mean lung dose, and lung V20. RESULTS: There were no significant differences in PTV coverage between the two techniques (FB vs. DIBH). The mean doses delivered to the coronary arteries, heart, and lungs were significantly reduced by 15% to 20% using DIBH compared with FB, and the lung V20 was reduced by almost one third. The dose reduction to organs at risk was greater for masses in the upper part of the mediastinum. IMRT with DIBH was partially implemented in 1 patient. This combination will be extended to other patients in the near future. CONCLUSIONS: Radiation exposure of the coronary arteries, heart, and lungs in patients with mediastinal Hodgkin's lymphoma was greatly reduced using DIBH with IMRT. The greatest benefit was obtained for tumors in the upper part of the mediastinum. The possibility of a wider use in clinical practice is currently under investigation in our department.
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Doença de Hodgkin/radioterapia , Inalação , Neoplasias do Mediastino/radioterapia , Radioterapia de Intensidade Modulada/métodos , Vasos Coronários/efeitos da radiação , Fracionamento da Dose de Radiação , Coração/efeitos da radiação , Doença de Hodgkin/diagnóstico por imagem , Humanos , Pulmão/efeitos da radiação , Neoplasias do Mediastino/diagnóstico por imagem , Órgãos em Risco/efeitos da radiação , Radiografia , Espirometria/instrumentação , Carga TumoralRESUMO
PURPOSE: To assess the clinical outcome of the involved-node radiotherapy (INRT) concept using modern radiation treatments (intensity-modulated radiotherapy [IMRT] or deep-inspiration breath-hold radiotherapy [DIBH) in patients with localized supradiaphragmatic Hodgkin lymphoma. METHODS AND MATERIALS: All but 2 patients had early-stage Hodgkin lymphoma, and they were treated with chemotherapy prior to irradiation. Radiation treatments were delivered using the INRT concept according to European Organization for Research and Treatment of Cancer guidelines. IMRT was performed with the patient free-breathing. For the adapted breath-hold technique, a spirometer dedicated to DIBH radiotherapy was used. Three-dimensional conformal radiotherapy was performed with those patients. RESULTS: Fifty patients with Hodgkin lymphoma (48 patients with primary Hodgkin lymphoma, 1 patient with recurrent disease, and 1 patient with refractory disease) entered the study from January 2003 to August 2008. Thirty-two patients were treated with IMRT, and 18 patients were treated with the DIBH technique. The median age was 28 years (range, 17-62 years). Thirty-four (68%) patients had stage I - (I-IIA) IIA disease, and 16 (32%) patients had stage I - (I-IIB) IIB disease. All but 3 patients received three to six cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD). The median radiation doses to patients treated with IMRT and DIBH were, respectively, 40 Gy (range, 21.6-40 Gy) and 30.6 Gy (range, 19.8-40 Gy). Protection of various organs at risk was satisfactory. Median follow-up was 53.4 months (range, 19.1-93 months). The 5-year progression-free and overall survival rates for the whole population were 92% (95% confidence interval [CI], 80%-97%) and 94% (95% CI, 75%-98%), respectively. Recurrences occurred in 4 patients: 2 patients had in-field relapses, and 2 patients had visceral recurrences. Grade 3 acute lung toxicity (transient pneumonitis) occurred in 1 case. CONCLUSIONS: Our results suggest that patients with localized Hodgkin lymphoma can be safely and efficiently treated using the INRT concept and modern radiation treatment techniques such as IMRT and DIBH.
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Doença de Hodgkin/radioterapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bleomicina/administração & dosagem , Terapia Combinada/métodos , Dacarbazina/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Humanos , Inalação/fisiologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Lesões por Radiação/prevenção & controle , Radiografia , Radioterapia/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Espirometria/instrumentação , Vimblastina/administração & dosagem , Adulto JovemRESUMO
PURPOSE: To compare the dose distribution between three-dimensional conformal radiotherapy (3DCRT), intensity modulated radiotherapy (IMRT) with six coplanar beams (6b-IMRT) and IMRT with nine coplanar beams (9b-IMRT) during adjuvant radiotherapy for retroperitoneal sarcoma. METHODS AND MATERIALS: The 10 most recent patients who had received adjuvant radiotherapy were reviewed. Three different treatment plans were generated (3DCRT, 6b-IMRT and 9b-IMRT) to deliver 50.4 Gy in 28 fractions. The dose delivered to the organs at risk (intestinal cavity (IC), contra- and ipsilateral kidney, liver, stomach and whole body), and the conformity index (CI) were compared. RESULTS: The integral dose to the intestinal cavity was similar with the three modalities but the dose distribution was different, with a change-over around 25 Gy: the V50 and the V40 were reduced five- and twofold, respectively, with IMRT compared to 3DCRT, and the V20 was increased by about 25% with IMRT. A similar integral dose was delivered to the whole body with the three modalities. The treated volume (V95 body) was approximately halved with IMRT compared to 3DCRT, and the CI was twice as good with IMRT than with 3DCRT. As expected, the V5 (body) was higher with IMRT compared to 3DCRT (p<0.0001) (a 12% increase with 6b-IMRT and a 21% increase with 9b-IMRT). Compared to 3DCRT, the mean dose delivered to the contralateral kidney increased from 1.5 to 4-4.4 Gy with IMRT. The number of monitor units was increased with IMRT, especially when nine beams were used instead of six. CONCLUSIONS: As expected, IMRT greatly reduced the high-dose irradiated volume and increased the low-dose exposure of the intestinal cavity, with a change-over around 25 Gy, compared to 3DCRT. The conformity index was compellingly better with IMRT. The integral dose delivered to the whole body was conserved with both 3DCRT and IMRT. Longer follow-up is needed to assess late toxicities to the small bowel, contralateral kidney and the risk of second cancers.
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Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias Retroperitoneais/radioterapia , Sarcoma/radioterapia , Adulto , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Radioterapia Adjuvante , Neoplasias Retroperitoneais/diagnóstico por imagem , Sarcoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
Small-cell lung carcinomas (SCLC) represent less than 20% of all lung cancers. As it is an aggressive tumour, on account of its high and early risk of dissemination, only a third of patients have limited-stage disease at diagnosis. For these patients, the current state-of-the-art treatment involves cisplatin-etoposide chemotherapy combined with chest radiotherapy. Because of the high risk of brain metastases, prophylactic cranial irradiation (PCI) is indicated in good responders and should be part of the standard management of these patients on the basis of a PCI meta-analysis showing a 5% increase in survival at 3 years. The 5-year survival rate reaches 25% in the best series. This progress is subsequent to a better combination of polychemotherapy and both thoracic and cerebral irradiation. In extensive disease, radiotherapy has also a place in the management of SCLC: PCI reduces the risk of brain metastases and significantly improves overall survival, so that cisplatin (or carboplatin)-etoposide followed by PCI in responding patients has become the standard treatment. Many issues are subject for further clinical research concerning timing, volume and schedule of thoracic radiotherapy to be used in combination with chemotherapy regimen. Progress in thoracic radiotherapy can only be achieved by including patients in prospective studies.