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Braquiterapia , Realidade Virtual , Humanos , Braquiterapia/métodos , Simulação por ComputadorRESUMO
Background: We describe a case of a supratentorial ependymoma, zinc finger translocation-associated (ZFTA) fusion positive with extensive synaptophysin immunoreactivity arising from malignant transformation of an ependymoma with clear cell features in a patient with long-term follow-up. Case Description: A 55-year-old woman presented with seizures and ataxia 15 years after an initial resection of a clear cell ependymoma, Grade 2. Imaging demonstrated an enhancing right paracentral mass and the patient underwent biopsy and resection. Microscopic analysis showed regions of the tumor with morphological and immunohistochemical features typical of ependymoma, including perivascular pseudorosettes and focal dot- like epithelial membrane antigen positivity, as well as high-grade features. In addition, the neoplasm contained large nodular regions of clear cells exhibiting extensive synaptophysin immunoreactivity, suggestive of neural differentiation, and only focally positive immunoreactivity for glial markers. Electron microscopy showed poorly formed and ill-defined junctional complexes, but no cilia, microvilli, or dense granules were seen. Molecular profiling revealed the presence of a fusion between ZFTA (previously known as C11orf95) and RELA fusion. Conclusion: We report a case of extensive synaptophysin immunoreactivity in a ZFTA-RELA fusion-positive ependymoma that had undergone malignant transformation from a clear cell ependymoma and has long-term follow-up, contributing to the assessment of prognostic significance of synaptophysin immunoreactivity in supratentorial ependymoma, ZFTA fusion positive.
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Cavernous hemangiomas, or cavernomas, are vascular malformations that affect about 0.1-0.5% of the population and usually result from sporadic or familial mutations of genes involved with endothelial cell junctions. They are histologically described as dilated vascular clusters, and they may occur in various areas of the body. Cavernomas of the central nervous system can generate localizing symptoms, including focal neurological defects, headaches, seizures, and hemorrhage. Radiation-induced cavernomas (RICs) have been described in the literature since 1994 and have been more frequently described in children. Although there has been speculation about the pathophysiology of RICs, no consensus exists in the literature, and pathological evaluation of RICs remains sparsely reported. We present the case of a 63-year-old patient who underwent stereotactic radiosurgery for treatment of an intracranial arteriovenous malformation (AVM) and subsequently developed a symptomatic RIC seven years later that required microresection. Clinicians should exercise diligence when monitoring patients with a history of intracranial radiation because of growing evidence supporting cavernomas as potential late-stage sequelae.
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PURPOSE: To compare the accuracy of two separate models when calculating dose distributions in patients undergoing stereotactic radiosurgery (SRS) treatment for brain cancer. METHODS: For this comparison, two dose calculation algorithms were evaluated on two different treatment planning systems (TPS): Elekta's Monaco Version 5.11.00 Monte Carlo Gold Standard XVMC algorithm and Brainlab's iPlan Pencil Beam algorithm. The DICOM files of 11 patients with a total of 19 targets were exported from iPlan and then imported into Monaco to be recalculated. Using the dose distributions of the original (pencil beam/PB) and recalculated (Monte Carlo/MC) plans, four indices for plan quality were evaluated: coverage (Q), conformity index (CIRTOG), homogeneity index (HI), and gradient index (GI). RESULTS: There was a significant difference in the CIRTOG and HI between the two TPS calculations. However, the magnitude of these differences is often not substantial enough to cause the plan to fall outside of RTOG protocol deviation limits. Only 3 of the 19 targets had CIRTOG values which moved to a new level of deviation, and these targets were unique in terms of size (<0.1 cm3). CONCLUSION: It was found that the difference between systems is often not enough to cause the plan to fall outside of RTOG protocol deviation limits. This is an indication that a PB-based treatment planning system is sufficient for the mostly homogeneous conditions of intracranial SRS planning when the target is larger than 0.1 cm3. If below 0.1 cm3, the prescribing physician may need to evaluate TPS differences.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Método de Monte Carlo , Radiocirurgia/métodos , HumanosRESUMO
BACKGROUND: The prevention of radiation-induced liver disease (RILD) is very significant in ensuring a safe radiation treatment and high quality of life. AIMS AND OBJECTIVES: The purpose of this study is to investigate the correlation of physical and biological effective dose (BED) metrics with liver toxicity from hypo-fractionated liver radiotherapy. MATERIALS AND METHODS: 41 hypo-fractionated patients in 2 groups were evaluated for classic radiation-induced liver disease (RILD) and chronic RILD, respectively. Patients were graded for effective toxicity (post-treatment minus pre-treatment) using the Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Physical dose (PD) distributions were converted to BED. The V10Gy, V15Gy, V20Gy, V25Gy and V30Gy physical dose-volume metrics were used in the analysis together with their respective BED-converted metrics of V16.7Gy3, V30Gy3, V46.7Gy3, V66.7Gy3 and V90Gy3. All levels were normalized to their respective patient normal liver volumes (NLV) and evaluated for correlation to RILD. Results were measured quantitatively using R2 regression analysis. RESULTS: The classic RILD group had median follow-up time of 1.9 months and the average PD-NLV normalized V10Gy, V15Gy, V20Gy, V25Gy and V30Gy metrics per grade were plotted against RILD yielding R2 correlations of 0.84, 0.72, 0.73, 0.65 and 0.70, respectively while the BED-volume metrics of V16.7Gy3, V30Gy3, V46.7Gy3, V66.7Gy3 and V90Gy3 resulted in correlation values of 0.84, 0.74, 0.66, 0.78 and 0.74, respectively. BED compared to PD showed a statistically significant (p=.03) increase in R2 for the classic RILD group. Chronic RILD group had median follow-up time of 12.3 months and the average PD-NLV normalized V10Gy, V15Gy, V20Gy, V25Gy and V30Gy metrics per grade were plotted against RILD grade yielding R2 correlations of 0.48, 0.92, 0.88, 0.90 and 0.99 while the BED-volume metrics of V16.7Gy3, V30Gy3, V46.7Gy3, V66.7Gy3 and V90Gy3 resulted in correlation values of 0.43, 0.94, 0.99, 0.21 and 0.00, respectively. CONCLUSION: The strong correlations of the V10Gy and V15Gy PD-volume metrics as well as the V16.7Gy3 (BED of V10Gy) to both classic and chronic RILD imply the appropriateness of the current 15Gy evaluation level for liver toxicity with hypo-fractionated treatments.
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PURPOSE: The purpose of this study was to investigate the dosimetric equivalency of dynamic conformal arc therapy (DCAT) against volumetric modulated arc therapy (VMAT) plans in stereotactic body radiation therapy (SBRT) of lung and liver lesions and to examine if efficiency can be increased. METHODS: Nineteen patients previously treated for lung and liver cancer lesions with SBRT were included. Organs at risk (OAR) and targets were contoured by a single radiation oncologist. All plans were optimized by the same dosimetrist using ELEKTA Monaco treatment planning system version 5.0 for 6MV flattening filter free (FFF) photon beam in a VersaHD (ELEKTA, Crawley, UK). A VMAT and DCAT plan was optimized using the same objectives using coplanar arcs of 225o arc span. RESULTS: All plans have achieved the target and OAR planning objectives. The target dose conformity was comparable (mean VMAT PTVr=1.3 and DCAT PTVr=1.4), and the low dose spillage were similar (mean VMAT R50=4.5 and DCAT R50=4.6). However, monitor units (MU) for DCAT plans were lower by 2.5 times on average than VMAT plans. It was observed that in 75% of cases where OARs overlapped with the PTV, maximum doses to OAR were higher in VMAT than DCAT plans, but the difference was not significant. Patient specific quality assurance (QA) plans were measured using the Scandidos Delta4 phantom and gamma analysis performed using 2mm distance to agreement (DTA) and 2% dose difference yielded more than 95% passing rates on both VMAT and DCAT plans. CONCLUSIONS: DCAT delivery for lung and liver SBRT is a dosimetrically equivalent and an efficient alternative to VMAT plans.
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Neoplasias Hepáticas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia , Radioterapia de Intensidade Modulada , Feminino , Humanos , Fígado/patologia , Fígado/efeitos da radiação , Neoplasias Hepáticas/patologia , Pulmão/patologia , Pulmão/efeitos da radiação , Neoplasias Pulmonares/patologia , Masculino , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional/métodosRESUMO
PURPOSE: The Brainlab Elements treatment planning system utilizes distinct modules for treatment planning specific to stereotactic treatment sites including single or multiple brain lesions as well as spine. This work investigates the hypothesis that an optimization tailored specifically to spine can in fact create dosimetrically superior plans to those created in more general use treatment planning systems (TPS). METHODS: Ten spine patients at our institution were replanned in Brainlab Elements, Phillips Pinnacle3 , and Elekta Monaco. The planning target volume (PTV) included the vertebral body (in either the thoracic or lumbar spine), pedicles, and transverse processes. In all plans, the target was prescribed 20 Gy to 95% of the PTV. Objectives for the study included D5%<25 Gy and spinal cord D0.035cc < 14 Gy. Plans were evaluated by the satisfaction of the objectives as well total monitor units (MU), gradient index (GI), conformity index (CI), and dose gradient (distance between 100% and 50% isodose lines) in a selected slice between the vertebral body and spinal cord. RESULTS: All TPS produced clinically acceptable plans. The sharpest dose gradient was achieved with Elements (mean 3.3 ± 0.2 mm). This resulted in lowest spinal cord maximum point doses (6.6 ± 1.0 Gy). Gradient indices were also the smallest for Elements (3.6 ± 0.5). Further improvement in gradient index and spinal cord sparing were not performed due to the subsequent violation of the PTV D5% < 25 Gy constraint or the loss of conformity due to the loss of coverage at the PTV-spinal canal interface. CONCLUSIONS: Brainlab Elements planning which relies on arc duplication to specifically optimize for spine anatomy did result in dosimetrically superior plans while holding prescription levels constant. While any planning system can improve upon specific dosimetric objectives, the simultaneous satisfaction of all constraints was best achieved with Brainlab Elements.
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Órgãos em Risco/efeitos da radiação , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias da Coluna Vertebral/cirurgia , Humanos , Dosagem RadioterapêuticaRESUMO
PURPOSE: To develop and validate an intensity modulated radiation therapy (IMRT) treatment plan quantitative score using QUANTEC dose/volume parameters to assess plan quality. METHODS: 132 IMRT and volumetric modulated Arc therapy (VMAT) patient plans of various treatment sites were evaluated. The optimized plan's dose volume histogram (DVH) was exported to Velocity for evaluation. The proposed scoring was based on calculating the shortest distance from the QUANTEC objective to the DVH line of each organ. Each plan was normalized against the ideal plan where the organs at risk (OARs) received no dose and hence the distance between the QUANTEC objective and the DVH line was maximized. These normalized scores enabled the comparison of the quality of plans across treatment sites and dosimetrists. The scores were plotted and statistically analyzed to serve as a basis for future research. RESULTS: The score for each treatment site was evaluated and the average percentage scores±SD were found to be 43.5 ± 21.0, 33.3 ± 31.7, 42.6 ± 23.3, 40.2 ± 24.4, 33.5 ± 23.5 for the sites of abdomen, brain, chest, head/neck, and pelvis respectively. Differences in scores between the treatment sites were largely attributed to OAR segmentation and proximity of the OAR to the planning target volume (PTV). Small score differences between dosimetrists were attributed to the number of plans they have completed. CONCLUSION: This approach allows comparison of patient treatments which will help improve patient care and treatment outcomes. A larger sample of treatment plans is being evaluated to investigate the effect of dosimetrist's experience on plan quality.
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Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Radioterapia/métodos , Humanos , Radioterapia/normas , Dosagem RadioterapêuticaRESUMO
INTRODUCTION: With the advent of complex treatment techniques like volumetric modulated arc therapy, there has been increasing interest in treatment planning technologies aimed at reducing planning time. One of these such technologies is auto-planning, which is an automated planning module within Pinnacle3. This study seeks to retrospectively evaluate the dosimetric quality of auto-planning-derived treatment plans as they compare to manual plans for intact prostate, prostate and lymph nodes, and brain treatment sites. MATERIALS AND METHODS: Previous clinical plans were used to generate site-specific auto-planning templates. These templates were used to compare the 3 evaluated treatment sites. Plans were replanned using auto-planning and compared to the clinically delivered plans. For the planning target volume, the following metrics were evaluated: homogeneity index, conformity index, D2cc, Dmean, D2%, D98%, and multiple dose fall-off parameters. For the organs at risk, D2cc, Dmean, and organ-specific clinical metrics were evaluated. Statistical differences were evaluated using a Wilcoxon paired signed-rank test with a significance level of 0.05. Statistically significant ( P < 0.05) differences were noted in organs at risk sparing. RESULTS: For the prostate, there was as much as 6.8% reduction in bladder Dmean and 23.5% reduction in penile bulb Dmean. For the prostate + lymph nodes, decreases in Dmean values ranging from 4.1% in the small bowel to 22.3% in the right femoral head were observed. For brain, significant improvements were observed in Dmax and Dmean to most organs at risk. CONCLUSION: Our study showed improved organs at risk sparing in most organs while maintaining planning target volume coverage. Overall, auto-planning can generate plans that delivered the same target coverage as the clinical plans but offered significant reductions in mean dose to organs at risk.
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Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Software , Algoritmos , Humanos , Órgãos em Risco , Doses de Radiação , Radiometria , Radioterapia de Intensidade Modulada/métodosRESUMO
BACKGROUND: The development of brain metastasis (BM) in patients with colorectal cancer (CRC) is a rare and late event. We sought to investigate the clinical characteristics, disease course and safety using biologic agents in our patients with CRC who develop brain metastases. METHODS: A retrospective review of patients with CRC with brain metastases treated at our institution from 01/2005-01/2015 was performed. Survival analysis was performed using the Kaplan-Meier method. RESULTS: Forty patients were included in the analysis. Median age was 55.5 years, 67.5% were males, and 28% had a KRAS mutation. Twenty-four percent were treatment-naive at the time of BM diagnosis. Patients had a median of two brain lesions. Sixty-five percent of the patients were treated with radiotherapy alone, 22.5% had both surgical resection and brain radiotherapy. Median overall survival was 3.2 months after development of BM. Overall survival was longer in patients who received combined modality local therapy compared to patients treated with surgical resection or radiotherapy alone. Patients who received systemic treatment incorporating biologics following development of BM had a median overall survival of 18.6 months. Overall, the administration of biologic agents was safe and well tolerated. CONCLUSIONS: In summary, BM is an uncommon and late event in the natural history of metastatic CRC. The ability to deliver combined-modality local brain therapy as well as availability of more systemic therapy options appear to lead to improved outcomes.
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BACKGROUND: In this treatment planning study, we compare the plan quality and delivery parameters for the treatment of multiple brain metastases using 2 monoisocentric techniques: the Multiple Metastases Element from Brainlab and the RapidArc volumetric-modulated arc therapy from Varian Medical Systems. METHODS: Eight patients who were treated in our institution for multiple metastases (3-7 lesions) were replanned with Multiple Metastases Element using noncoplanar dynamic conformal arcs. The same patients were replanned with the RapidArc technique in Eclipse using 4 noncoplanar arcs. Both techniques were designed using a single isocenter. Plan quality metrics (conformity index, homogeneity index, gradient index, and R50%), monitor unit, and the planning time were recorded. Comparison of the Multiple Metastases Element and RapidArc plans was performed using Shapiro-Wilk test, paired Student t test, and Wilcoxon signed rank test. RESULTS: A paired Wilcoxon signed rank test between Multiple Metastases Element and RapidArc showed comparable plan quality metrics and dose to brain. Mean ± standard deviation values of conformity index were 1.8 ± 0.7 and 1.7 ± 0.6, homogeneity index were 1.3 ± 0.1 and 1.3 ± 0.1, gradient index were 5.0 ± 1.8 and 5.1 ± 1.9, and R50% were 4.9 ± 1.8 and 5.0 ± 1.9 for Multiple Metastases Element and RapidArc plans, respectively. Mean brain dose was 2.3 and 2.7 Gy for Multiple Metastases Element and RapidArc plans, respectively. The mean value of monitor units in Multiple Metastases Element plan was 7286 ± 1065, which is significantly lower than the RapidArc monitor units of 9966 ± 1533 ( P < .05). CONCLUSION: For the planning of multiple brain lesions to be treated with stereotactic radiosurgery, Multiple Metastases Element planning software produced equivalent conformity, homogeneity, dose falloff, and brain V12 Gy but required significantly lower monitor units, when compared to RapidArc plans.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Radiocirurgia , Radioterapia de Intensidade Modulada , Algoritmos , Neoplasias Encefálicas/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Carga TumoralRESUMO
p53 activation is a primary mechanism underlying pathological responses to DNA damaging agents such as chemotherapy and radiotherapy. Our recent animal studies showed that low dose arsenic (LDA)-induced transient p53 inhibition selectively protected normal tissues from chemotherapy-induced toxicity. Study objectives were to: 1) define the lowest safe dose of arsenic trioxide that transiently blocks p53 activation in patients and 2) assess the potential of LDA to decrease hematological toxicity from chemotherapy. Patients scheduled to receive minimum 4 cycles of myelosuppressive chemotherapy were eligible. For objective 1, dose escalation of LDA started at 0.005 mg/kg/day for 3 days. This dose satisfied objective 1 and was administered before chemotherapy cycles 2, 4, and 6 for objective 2. p53 level in peripheral lymphocytes was measured on day 1 of each cycle by ELISA assay. Chemotherapy cycles 1, 3, and 5 served as the baseline for the subsequent cycles of 2, 4, and 6 respectively. If p53 level for the subsequent cycle was lower (or higher) than the baseline cycle, p53 was defined as "suppressed" (or "activated") for the pair of cycles. Repeated measures linear models of CBC in terms of day, cycle, p53 activity and interaction terms were used. Twenty-six patients treated with 3 week cycle regimens form the base of analyses. The mean white blood cell, hemoglobin and absolute neutrophil counts were significantly higher in the "suppressed" relative to the "activated" group. These data support the proof of principle that suppression of p53 could lead to protection of bone marrow in patients receiving chemotherapy. This trial is registered in ClinicalTrials.gov. Identifier: NCT01428128.
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Antineoplásicos/efeitos adversos , Arsênio/administração & dosagem , Medula Óssea/efeitos dos fármacos , Proteína Supressora de Tumor p53/antagonistas & inibidores , Relação Dose-Resposta a Droga , HumanosRESUMO
In this study, a clinical evaluation of the Body Pro-Lok™ System combined with the TomoTherapy megavoltage computed tomography (MVCT) was performed for lung and liver stereotactic body radiotherapy (SBRT) to reduce interfractional setup uncertainty. Twenty patients treated with 3-5 fractions of SBRT were analyzed retrospectively. The Body Pro-Lok™ system was used in both CT simulation and during patient treatment setup. Patients were immobilized with a vacuum cushion placed posteriorly over the thoracic region, an abdominal compression plate, and a knee and foot sponge. Pretreatment MVCT scans of the TomoTherapy HI-ART II unit were fused with the planning kVCT before delivery of each fraction to determine the interfractional setup error. A total of 84 shifts were analyzed to assess the interfractional setup accuracy. Results showed that the mean interfractional setup errors and standard deviations were -0.9 ± 3.1 mm, 1.2 ± 5.5 mm, and 6.5 ± 2.6 mm for lateral (IEC-X), longitudinal (IEC-Y), and vertical (IEC-Z) variations, respectively. The maximum motion was 17.1 mm in the longitudinal direction. When all 3 translational coordinates were analyzed, a mean composite displacement vector of 8.2 ± 2.0 mm (range 4.1-11.7 mm) was obtained for all patients. Based on the findings, image-guided SBRT using the Body Pro-Lok™ system in conjunction with the MVCT of TomoTherapy is capable of minimizing interfractional setup error and improving treatment accuracy.
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Imobilização/instrumentação , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/cirurgia , Radiocirurgia/instrumentação , Radioterapia Conformacional/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
During helical tomotherapy, gantry angle accuracy is one of the vital geometric factors that assure accurate dose delivery to the target and organs at risk adjacent to it. The purpose of this study is to investigate the dosimetric impact of gantry angle misalignment on the target volume and critical organs during helical tomotherapy treatment. Five prostate cases were chosen to calculate the effects of gantry angle deviations on both patient-specific delivery quality assurance (DQA) and helical tomotherapy treatment plans. For DQA plans, the cheese phantom was rotated for up to +/-5 degrees from the preset position to simulate the gantry angle deviations during tomotherapy. Point doses at 5 mm below the isocenter and the dose distribution for each gantry angle were measured and reconstructed, respectively. For helical tomotherapy treatment plans, the same gantry misalignment effect was simulated by adjusting the automatic roll correction for up to +/-5 degrees using Planned Adaptive software. Variations of dose volume histograms (DVHs) and isodose lines were evaluated for both target and critical organs. There was no significant difference found, however, among the point dose measurements for gantry rotation up to +/-5 degrees in DQA plans. Shifts of isodose lines could be observed for gantry rotations larger than +/-27 degrees. Dosimetric discrepancies (less than 2%) were also found among DVHs of the PTV in the cases when gantry angle misalignment was larger than +/-2 degrees. However, for DVHs of either bladder or rectum under different gantry rotations, no significant differences were detected when gantry angle errors were up to +/-5 degrees. In summary, point dose measurements alone cannot reveal the dosimetric deviation due to gantry angle misalignment in DQA plans. For a 5 degrees gantry deviation, the dose to PTV increased by 0.5% comparing to the planned dose. The influence on organs at risk, i.e., rectum and bladder, is also negligible. Further studies are needed on the dosimetric impacts of gantry angle deviations for other treatment sites.
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Neoplasias da Próstata/radioterapia , Radiometria/métodos , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia/instrumentação , Calibragem , Relação Dose-Resposta à Radiação , Desenho de Equipamento , Humanos , Masculino , Movimento , Neoplasias da Próstata/terapia , Controle de Qualidade , Radioterapia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Software , Resultado do TratamentoRESUMO
BACKGROUND: Stereotactic radiosurgery is well established for the treatment of intracranial neoplasms but its use for lung tumors is novel. METHODS: Twenty-three patients with biopsy-proven lung tumors were recruited into a two-institution, dose-escalation, phase I clinical trial using a frameless stereotactic radiosurgery system (CyberKnife). Fifteen patients had primary lung tumors and 8 had metastatic tumors. The age range was 23 to 87 years (mean, 63 years). After undergoing computed tomography-guided percutaneous placement of two to four small metal fiducials directly into the tumor, patients received 1,500 cGY of radiation in a single fraction using a linear accelerator mounted on a computer-controlled robotic arm. Safety, feasibility, and efficacy were studied. RESULTS: Nine patients were treated with a breath-holding technique, and 14 with a respiratory-gating, automated, robotic technique. Tumor size ranged from 1 to 5 cm in maximal diameter. There were four complications related to fiducial placement: three pneumothoraces requiring chest tube insertion and one emphysema exacerbation. There were no grade 3 to 5 radiation-related complications. Follow-up ranged from 1 to 26 months (mean, 7.0 months). Radiographic response was scored as complete in 2 patients, partial in 15, stable in 4, and progressive in 2. Four patients died of non-treatment-related causes at 1, 5, 9, and 11 months after radiation. CONCLUSIONS: Single-fraction stereotactic radiosurgery is safe and feasible for the treatment of selected lung tumors. Additional studies are planned to investigate the optimal radiation dose, best motion-suppression technique, and overall treatment efficacy.
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Neoplasias Pulmonares/cirurgia , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , SegurançaRESUMO
OBJECTIVES: To determine whether Cyberknife technology can be applied to renal tissue safely and effectively. The goal was to achieve the high efficacy of a surgical treatment, with the low morbidity of a noninvasive intervention. METHODS: The Cyberknife is a frameless, image-guided radiosurgical device. This innovative extracorporeal treatment combines a linear accelerator mounted on a highly maneuverable robotic arm. The Cyberknife is unique in that it divides the high-dose radiation necessary to ablate the lesion completely into up to 1200 beams. Each one of these beams of radiation has a significantly reduced dose. Therefore, the individual dose of each beam is essentially benign to the pathway and surrounding tissue. However, at the focal point of these beams, the dose is additive, and the desired ablative dose is attained. Predetermined "lesions" in 16 kidneys were treated in vivo in the porcine model. Complete treatment was accomplished in one session per animal, with no complications. Gross and histologic evaluations were completed at 4, 6, or 8 weeks. RESULTS: The degree of radiation changes correlated with longer treatment intervals. After 8 weeks, the lesions showed complete fibrosis. The zones of complete fibrosis were characterized by dense, paucicellular connective tissue completely devoid of all normal kidney elements, including tubules and glomeruli. CONCLUSIONS: This initial preclinical evaluation of the Cyberknife for extracorporeal renal tissue ablation appears to be very promising and demonstrated its ability to ablate a targeted area precisely and completely with relative sparing of the surrounding tissue. This innovative technology introduces an exciting approach as a potential treatment option of renal masses in the future.
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Rim/cirurgia , Aceleradores de Partículas/instrumentação , Radiocirurgia/instrumentação , Técnicas Estereotáxicas , Animais , Carcinoma de Células Renais/cirurgia , Estudos de Avaliação como Assunto , Feminino , Rim/patologia , Rim/efeitos da radiação , Neoplasias Renais/cirurgia , Modelos Animais , Radiocirurgia/métodos , Radioterapia Assistida por Computador , Radioterapia Conformacional/métodos , Robótica/métodos , SuínosRESUMO
PURPOSE: To analyze the factors that affect survival in patients with brain metastases (BM) from breast cancer who were treated with whole brain radiotherapy (WBRT). METHODS AND MATERIALS: We identified 116 women with breast cancer who were treated with WBRT alone between February 1984 and September 2000. All patients had treatment and follow-up data available in their medical charts, which we extracted for this retrospective study. We evaluated a number of potential predictors of survival after WBRT: age, primary tumor stage, control of primary tumor, presence of other systemic metastases, site of systemic metastases, Karnofsky performance status, Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis class, total dose of WBRT, and number of BM. Eighteen patients received a total dose >3000 cGy and 7 received a partial brain boost. RESULTS: For the entire cohort, the median survival from the start of WBRT was 4.2 months. The 1-year survival rate was 17%, and the 2-year survival rate was 2%. Using univariate analysis, only Karnofsky performance status (p = 0. 0084), recursive partitioning analysis class (p = 0. 0147), and total WBRT dose (p = 0.0001) were predictive of longer survival. In multivariate analysis, Karnofsky performance status was the only significant predictor. CONCLUSION: Overall survival in breast cancer patients with BM treated with WBRT is poor. We recommend breast cancer patients with BM be enrolled in prospective trials to improve results.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Neoplasias da Mama , Irradiação Craniana/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Neoplasias Encefálicas/mortalidade , Neoplasias da Mama/mortalidade , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Before breast conservation can be offered to a woman with breast cancer one must understand both the indications and contraindications to such an approach. Factors that play a role in this decision include tumor-related factors and factors related to the expected cosmetic outcome following breast conservation. Here we present a case of a woman with epidermolysis bullosa simplex (EBS), a rare skin disorder that is characterized by blister formation following minor trauma, who underwent successful breast conservation.