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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 847 records · Page 47
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Uterine Artery Embolization versus Myomectomy: Impact on Quality of Life-Results of the FUME (Fibroids of the Uterus: Myomectomy versus Embolization) Trial

Purpose: This study was designed to compare quality of life (QoL) outcomes after uterine artery embolization (UAE) or myomectomy. Methods: Women with symptomatic fibroids diagnosed by ultrasound who wished to preserve their uterus were randomized to myomectomy (n = 81) or UAE (n = 82). Endpoints at 1 year were QoL measured by a validated questionnaire, hospital stay, rates of complications, and need for reintervention. Results: UAE patients had shorter hospitalization (2 vs. 6 days, p < 0.001). By 1 year postintervention, significant and equal improvements in QoL scores had occurred in both groups (myomectomy n = 59; UAE n = 61). There had been two (2.9%) major complications among UAE versus 6 (8%) among myomectomy patients (not significant). By 2 years, among UAE patients (n = 57) there were eight (14.0%) reinterventions for inadequate symptom control compared with one (2.7%) among myomectomy patients (n = 37). Half of the women who required hysterectomy had concomitant adenomyosis missed by US. Conclusions: UAE and myomectomy both result in significant and equal improvements in QoL. UAE allows a shorter hospital stay and fewer major complications but with a higher rate of reintervention.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Thrombin Injection Failure with Subsequent Successful Stent-Graft Placement for the Treatment of an Extracranial Internal Carotid Pseudoaneurysm in a 5-Year-Old Child

Internal carotid artery pseudoaneurysm is a rare life-threatening condition that may develop in different clinical situations. We report the case of an extracranial internal carotid artery pseudoaneurysm secondary to a throat infection in a pediatric patient that was initially treated with percutaneous thrombin injection under ultrasound guidance. However, recanalization occurred at 48 h, and definitive treatment was then performed by endovascular stent-graft placement. We briefly review the clinical characteristics of this uncommon clinical condition as well as the treatment options.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Uterine Artery Embolization to Treat Uterine Adenomyosis with or without Uterine Leiomyomata: Results of Symptom Control and Health-Related Quality of Life 40 Months after Treatment

Purpose: To evaluate the clinical outcome for uterine adenomyosis with or without uterine leiomyomata 40 months after uterine artery embolization (UAE). Methods: Forty women aged 39-56 years (median 46 years) with symptomatic uterine adenomyosis and magnetic resonance imaging findings of uterine adenomyosis with or without combined uterine leiomyomata underwent UAE. Self-perceived changes in clinical symptoms were assessed, and residual symptom severity and health-related quality of life (HRQOL) after UAE were evaluated. Clinical failure was defined as no symptomatic improvement or second invasive therapy after UAE. Results were stratified by the extent of uterine adenomyosis at baseline magnetic resonance imaging. Results: Patients were followed for a median of 40 months (range 5-102 months). UAE led to symptomatic control after UAE in 29 (72.5%) of 40 patients while 11 women underwent hysterectomy (n = 10) or dilatation and curettage (n = 1) for therapy failure. No significant difference between women with pure uterine adenoymosis and women with uterine adenomyosis combined with uterine leiomyomata was observed. Best results were shown for UAE in uterine adenomyosis with uterine leiomyomata predominance as opposed to predominant uterine adenomyosis with minor fibroid disease (clinical failure 0% vs. 31.5%, P = 0.058). Throughout the study group, HRQOL score values increased and symptom severity scores decreased after UAE. Least improvement was noted for women with pure adenomyosis. Conclusions: UAE is clinically effective in the long term in most women with uterine adenomyosis. Symptomatic control and HRQOL were highest in patients with combined disease of uterine adenomyosis but leiomyomata predominance.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Percutaneous Treatment of an Infected Aneurysmal Sac Secondary to Aortoesophageal Fistula with a History of Stent-Graft Treatment for Thoracic Aortic Aneurysm

A 68-year-old man who was subjected to stent-grafting of a descending thoracic aortic aneurysm (TAA) 4 months previously was admitted to our hospital with constitutional symptoms, including high fever, sweating, nausea, vomiting, weight loss, and backache. An infected aneurysmal sac was suspected based on computed tomography (CT) findings, and an aortoesophageal fistula (AEF) was identified during esophagoscopy. CT-guided aspiration was performed using a 20-G Chiba needle, confirming the presence of infection. For treatment of the infected aneurysmal sac, CT-guided percutaneous catheter drainage in a prone position was performed under general anesthesia with left endobronchial intubation. Drainage catheter insertion was successfully performed using the Seldinger technique, which is not a standard treatment of an infected aneurysmal sac. Improvement in the patient's clinical condition was observed at follow-ups, and CT showed total regression of the collection in the aneurysmal sac.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

A Novel Carotid Device for Embolic Diversion: Lessons Learned from a 'First in Man' Trial in Patients with Atrial Fibrillation

Purpose: This study was designed to investigate a novel device that was developed to direct emboli away from the internal carotid artery to the external carotid artery to prevent embolic stroke while avoiding the necessity for anticoagulation with warfarin. Methods: A stent-like, self-expandable filter was developed consisting of fine cobalt alloy mesh. After promising preclinical animal testing, the device was implanted into the common carotid artery extending into the external carotid artery in three patients with atrial fibrillation, each of whom were at high-risk for cerebral emboli and were suboptimal candidates for anticoagulation. Follow-up was performed clinically and with carotid duplex ultrasound. Results: The implantation was successful in all three patients. Unrestricted flow through the filter was demonstrated in each patient at 6 months by duplex sonography. However, at 7 months ultrasound demonstrated occlusion of the internal carotid artery filter in one patient, which was subsequently confirmed by angiography. Subtotal filter occlusion occurred in a second patient at 14 months. Neither patient had clinical symptoms. Both internal carotid arteries were successfully recanalized using standard angioplasty techniques without complication. The third patient had completely normal carotid blood flow at 29 months follow-up. Conclusions: Implantation of a novel device intended to divert emboli away from the internal carotid artery was feasible, but resulted in occlusive neointimal proliferation in two of three patients. These results demonstrate a discrepancy from the findings of preclinical animal studies and human investigation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

A Review of Experimental Animal Radon Health Effects [Book Chapter]

Abundant epidemiological data from underground miners confirm that radon decay products (progeny) are carcinogenic, although the evidence is less conclusive on the quantitative risks of these exposures, especially for indoor air. The imprecision results principally from differences between exposures in mining and domestic environments and from uncertainties about the interaction between smoking and exposure to radon progeny. Experimental animal studies of radon-induced lung cancer are particularly valuable for understanding the carcinogenicity of human radon exposures in the home and in the workplace. Animals can be exposed to a variety of agents under carefully controlled conditions and then sacrificed for the study of developing lesions or held for their life span for tumor development. The doses to critical cells in the respiratory tract can be determined, and these in turn can be related to doses to critical cells in the respiratory tract of humans exposed to similar aerosols. The study of radon-induced mutations and changes in expression of oncogenes and tumor-suppressor genes as well as growth factors and growth factor receptors during tumor progression in animals also provides valuable evidence on the underlying mechanisms of radon carcinogenesis. This evidence, particularly that of the efficiency for oncogenic transformation at low dose rates, is crucial to the determination of the risk of lung cancer from exposure to indoor levels of radon. This review of animal health effects data emphasizes the carcinogenicity of radon exposures in rats; mechanistic data on radon-induced lung tumors in rats are currently sparse and are not reviewed here.

560162* -- Radionuclide Effects, Kinetics, & Toxic↗
DOE OSTI2010

Sources of toxicity and exposure information for identifying chemicals of high concern to children

Due to the large number of chemicals in commerce without adequate toxicity characterization data, coupled with an ineffective federal policy for chemical management in the United States, many states are grappling with the challenge to identify toxic chemicals that may pose a risk to human health and the environment. Specific populations (e.g., children, elderly) are particularly sensitive to these toxic chemicals. In 2008, the Children's Safe Product Act (CSPA) was passed in Washington State. The CSPA included specific requirements to identify High Priority Chemicals (HPCs) and Chemicals of High Concern to Children (CHCCs). To implement this legislation, a methodology was developed to identify HPCs from authoritative scientific and regulatory sources on the basis of toxicity criteria. Another set of chemicals of concern was then identified from authoritative sources, based on their potential exposure to children. Exposure potential was evaluated by identifying chemicals detected in biomonitoring studies (i.e., human tissues), as well as those present in residential exposure media (e.g., indoor air, house dust, drinking water, consumer products). Accordingly, CHCCs were defined as HPCs that also appear in biomonitoring studies or relevant exposure media. For chemicals with unique Chemical Abstracts Service (CAS) numbers, we identified 2044 HPCs and 2219 chemicals with potential exposure to children, resulting in 476 CHCCs. The process of chemical identification is dynamic, so that chemicals may be added or subtracted as new information becomes available. Although beyond the scope of this paper, the 476 CHCCs will be prioritized in a more detailed assessment, based on the strength and weight of evidence of toxicity and exposure data. Our approach was developed to be flexible which allows the addition or removal of specific sources of toxicity or exposure information, as well as transparent to allow clear identification of inputs. Although the methodology was constrained by specific requirements in the CSPA, the intent of this work was to identify HPCs and CHCCs that might guide future regulatory actions and inform chemical management policies, aimed at protecting children's health.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2010

Diagnostic health risk assessment of electronic waste on the general population in developing countries' scenarios

E-waste is the generic name for technological waste. Even though aspects related to e-waste environmental pollution and human exposure are known, scientific assessments are missing so far on the actual risks for health sustainability of the general population exposed to e-waste scenarios, such as illicit dumping, crude recycling and improper treatment and disposal. In fact, further to occupational and direct local exposure, e-waste scenarios may impact on the environment-to-food chain, thus eliciting a widespread and repeated exposure of the general population to mixtures of toxicants, mainly toxic chemical elements, polycyclic aromatic hydrocarbons and persistent organic pollutants. In the absence of any clear policy on e-waste flow management, the situation in the e-waste receiver countries may become quite scary; accordingly, here we address a diagnostic risk assessment of health issues potentially elicited by e-waste related mixtures of toxicants. Scientific evidence available so far (mainly from China) is discussed with special attention to the concept of health sustainability, i.e. the poor health burden heritage perpetuated through the mother-to-child dyad. Endocrine disruption and neurotoxicity are specifically considered as examples of main health burden issues relevant to perpetuation through life cycle and across generations; toxicological information are considered along with available data on environmental and food contamination and human internal exposure. The risk from exposure to e-waste related mixtures of toxicants of vulnerable subpopulation like breast-fed infants is given special attention. The diagnostic risk assessment demonstrates how e-waste exposure poses an actual public health emergency, as it may entrain significant health risks also for generations to come. Exposure scenarios as well as specific chemicals of major concern may vary in different contexts; for instance, only limited information is available on e-waste related exposures in a major site of e-waste dumping such as West Africa. Therefore, considerations are also given on data gaps possibly fitting a systematic risk assessment of the e-waste health impacts in different subscenarios as well as possible protective factors for exposed subpopulations.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2016

Underwater noise modelling for environmental impact assessment

Assessment of underwater noise is increasingly required by regulators of development projects in marine and freshwater habitats, and noise pollution can be a constraining factor in the consenting process. Noise levels arising from the proposed activity are modelled and the potential impact on species of interest within the affected area is then evaluated. Although there is considerable uncertainty in the relationship between noise levels and impacts on aquatic species, the science underlying noise modelling is well understood. Nevertheless, many environmental impact assessments (EIAs) do not reflect best practice, and stakeholders and decision makers in the EIA process are often unfamiliar with the concepts and terminology that are integral to interpreting noise exposure predictions. In this paper, we review the process of underwater noise modelling and explore the factors affecting predictions of noise exposure. Finally, we illustrate the consequences of errors and uncertainties in noise modelling, and discuss future research needs to reduce uncertainty in noise assessments.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2010

Young Men Have Equivalent Biochemical Outcomes Compared With Older Men After Treatment With Brachytherapy for Prostate Cancer

Purpose: To evaluate retrospectively the biochemical outcomes of young men treated with low-dose-rate brachytherapy for prostate cancer. Methods and Materials: From 1990 to 2005, 1,665 men with clinically localized prostate cancer were treated with low-dose-rate brachytherapy {+-} hormone therapy (HT) {+-} external beam radiotherapy and underwent {>=}2 years of follow-up. Patients were stratified on the basis of age: {<=}60 (n = 378) and >60 years (n = 1,287). Biochemical failure was defined as a prostate-specific antigen (PSA) nadir plus 2 ng/mL. Univariate and multivariate analyses were used to determine the association of variables with freedom from biochemical failure (FFbF). Results: Median follow-up was 68 months (range, 24-180) for men {<=}60 years and 66 months (range, 24-200) for men >60. For the entire group, the actuarial 5- and 8-year FFbF rates were 94% and 88%, respectively. Men {<=}60 demonstrated similar 5- and 8-year FFbF (95% and 92%) compared with men >60 (93% and 87%; p = 0.071). A larger percent of young patients presented with low-risk disease; lower clinical stage, Gleason score (GS), and pretreatment PSA values; were treated after 1997; did not receive any HT; and had a high biologic effective dose (BED) of radiation (all ps <0.001). On multivariate analysis, PSA (p = 0.001), GS (p = 0.005), and BED (p < 0.001) were significantly associated with FFbF, but age was not (p = 0.665). Conclusion: Young men achieve excellent 5- and 8-year biochemical control rates that are comparable to those of older men after prostate brachytherapy. Young age should not be a deterrent when considering brachytherapy as a primary treatment option for clinically localized prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Effect of Radiotherapy Interruptions on Survival in Medicare Enrollees With Local and Regional Head-and-Neck Cancer

Purpose: To investigate whether interruptions in radiotherapy are associated with decreased survival in a population-based sample of head-and-neck cancer patients. Methods and Materials: Using the Surveillance, Epidemiology, and End Results-Medicare linked database we identified Medicare beneficiaries aged 66 years and older diagnosed with local-regional head-and-neck cancer during the period 1997-2003. We examined claims records of 3864 patients completing radiotherapy for the presence of one or more 5-30-day interruption(s) in therapy. We then performed Cox regression analyses to estimate the association between therapy interruptions and survival. Results: Patients with laryngeal tumors who experienced an interruption in radiotherapy had a 68% (95% confidence interval, 41-200%) increased risk of death, compared with patients with no interruptions. Patients with nasal cavity, nasopharynx, oral, salivary gland, and sinus tumors had similar associations between interruptions and increased risk of death, but these did not reach statistical significance because of small sample sizes. Conclusions: Treatment interruptions seem to influence survival time among patients with laryngeal tumors completing a full course of radiotherapy. At all head-and-neck sites, the association between interruptions and survival is sensitive to confounding by stage and other treatments. Further research is needed to develop methods to identify patients most susceptible to interruption-induced mortality.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

DNA Repair Alterations in Children With Pediatric Malignancies: Novel Opportunities to Identify Patients at Risk for High-Grade Toxicities

Purpose: To evaluate, in a pilot study, the phosphorylated H2AX ({gamma}H2AX) foci approach for identifying patients with double-strand break (DSB) repair deficiencies, who may overreact to DNA-damaging cancer therapy. Methods and Materials: The DSB repair capacity of children with solid cancers was analyzed compared with that of age-matched control children and correlated with treatment-related normal-tissue responses (n = 47). Double-strand break repair was investigated by counting {gamma}H2AX foci in blood lymphocytes at defined time points after irradiation of blood samples. Results: Whereas all healthy control children exhibited proficient DSB repair, 3 children with tumors revealed clearly impaired DSB repair capacities, and 2 of these repair-deficient children developed life-threatening or even lethal normal-tissue toxicities. The underlying mutations affecting regulatory factors involved in DNA repair pathways were identified. Moreover, significant differences in mean DSB repair capacity were observed between children with tumors and control children, suggesting that childhood cancer is based on genetic alterations affecting DSB repair function. Conclusions: Double-strand break repair alteration in children may predispose to cancer formation and may affect children's susceptibility to normal-tissue toxicities. Phosphorylated H2AX analysis of blood samples allows one to detect DSB repair deficiencies and thus enables identification of children at risk for high-grade toxicities.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Ototoxicity After Intensity-Modulated Radiation Therapy and Cisplatin-Based Chemotherapy in Children With Medulloblastoma

Purpose: To report the incidence of Pediatric Oncology Group (POG) Grade 3 or 4 ototoxicity in a cohort of patients treated with craniospinal irradiation (CSI) followed by posterior fossa (PF) and/or tumor bed (TB) boost using intensity-modulated radiation therapy (IMRT). Methods and Materials: From 1998 to 2006, 44 patients with medulloblastoma were treated with CSI followed by IMRT to the PF and/or TB and cisplatin-based chemotherapy. Patients with standard-risk disease were treated with 18 to 23.4 Gy CSI followed by either a (1) PF boost to 36 Gy and TB boost to 54 to 55.8 Gy or (2) TB boost to 55.8 Gy. Patients with high-risk disease received 36 to 39.6 Gy CSI followed by a (1) PF boost to 54 to 55.8 Gy, (2) PF boost to 45 Gy and TB boost to 55.8 Gy, or (3) TB boost to 55.8 Gy. Median audiogram follow-up was 41 months (range, 11-92.4 months). Results: POG Grade Ototoxicity 0, 1, 2, 3. and 4 was found in 29, 32, 11, 13. and 3 ears. respectively, with POG Grade 3 or 4 accounting for 18.2% of cases. There was a statistically significant difference in mean radiation dose (D{sub mean}) cochlea according to degree of ototoxicity, with D{sub mean} cochlea increasing with severity of hearing loss (p = 0.027). Conclusions: Severe ototoxicity was seen in 18.2% of ears in children treated with IMRT boost and cisplatin-based chemotherapy. Increasing dose to the cochlea was associated with increasing severity of hearing loss.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Role of Radiation Dose in the Risk of Secondary Leukemia After a Solid Tumor in Childhood Treated Between 1980 and 1999

Purpose: The purpose of this study was to estimate the risk of secondary leukemia as a function of radiation dose, taking into account heterogeneous radiation dose distribution. Methods and Materials: We analyzed a case-control study that investigated the risk of secondary leukemia and myelodysplasia after a solid tumor in childhood; it included 61 patients with leukemia matched with 196 controls. Complete clinical, chemotherapy, and radiotherapy histories were recorded for each patient in the study. Average radiation dose to each of seven bone marrow components for each patient was incorporated into the models, and corresponding risks were summed up. Conditional maximum likelihood methods were used to estimate risk parameters. Results: Whatever the model, we failed to evidence a role for the radiation dose to active bone marrow in the risk of later leukemia, myelodysplasia, or myeloproliferative syndrome, when adjusting for epipodophyllotoxin and anthracycline doses. This result was confirmed when fitting models that included total dose of radiation delivered during radiotherapy, when fitting models taking into account dose per fraction, and when restricting the analysis to acute myeloid leukemia. Conclusions: In contrast to results found in similar studies that included children treated before the use of epipodophyllotoxins, this study failed to show a role for radiotherapy in the risk of secondary leukemia after childhood cancer in children treated between 1980 and 1999. This discrepancy was probably due to a competitive mechanism between these two carcinogens.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2010

Irradiation of Pediatric High-Grade Spinal Cord Tumors

Purpose: To report the outcome using radiation therapy (RT) for pediatric patients with high-grade spinal cord tumors. Methods and Materials: A retrospective chart review was conducted that included 17 children with high-grade spinal cord tumors treated with RT at St. Jude Children's Research Hospital between 1981 and 2007. Three patients had gross total resection, 11 had subtotal resection, and 3 underwent biopsy. The tumor diagnosis was glioblastoma multiforme (n = 7), anaplastic astrocytoma (n = 8), or anaplastic oligodendroglioma (n = 2). Seven patients received craniospinal irradiation (34.2-48.6 Gy). The median dose to the primary site was 52.2 Gy (range, 38-66 Gy). Results: The median progression-free and overall survivals were 10.8 and 13.8 months, respectively. Local tumor progression at 12 months (79% vs. 30%, p = 0.02) and median survival (13.1 vs. 27.2 months, p = 0.09) were worse for patients with glioblastoma multiforme compared with anaplastic astrocytoma or oligodendroglioma. The median overall survival was shorter for patients when failure included neuraxis dissemination (n = 8) compared with local failure alone (n = 5), 9.6 vs. 13.8 months, p = 0.08. Three long-term survivors with World Health Organization Grade III tumors were alive with follow-up, ranging from 88-239 months. Conclusions: High-grade spinal cord primary tumors in children have a poor prognosis. The propensity for neuraxis metastases as a component of progression after RT suggests the need for more aggressive therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Role of Palliative Radiotherapy in the Management of Metastatic Pediatric Neuroblastoma: A Retrospective Single-Institution Study

Purpose: Neuroblastoma is the most common extracranial solid tumor of childhood, and metastatic disease occurs in a majority of patients. Although radiotherapy (RT) plays an important role in the management of metastatic disease, data on the effectiveness of palliative RT, in this setting, is scarce. Methods and Materials: A retrospective review of the outcome of palliative RT in children with metastatic neuroblastoma was conducted at the Institut Curie. Results: Thirty-four children with 69 metastatic sites received palliative RT between 2000 and 2009. Sites of disease were grouped according to location, and there were 19 soft tissue, 38 bone, 9 central nervous system (CNS), and 3 hepatic metastases. Mean RT doses for the four groups were 19.6 Gy, 17.6 Gy, 17 Gy, and 5 Gy, respectively. Median survivals after RT were 27 days, 43 days, 29 days, and 27 days, respectively, for an overall median survival of 29.5 days. For the soft tissue metastases, good response was defined as a decrease >25% in the tumor mass or any decrease in pain; the response rate was 84.2%. Furthermore, a dose 15 Gy or more significantly increased response rate (100% vs. 57%; p = 0.038), compared with a dose smaller than 15 Gy. For the bone group and CNS metastases group, the overall response rates were 63.2% and 44%, respectively. A trend toward dose-response relationship was seen for the bone but not the CNS group. Conclusion: Good response rates are achieved with palliative RT for symptomatic metastatic pediatric neuroblastoma, but survival is dismal.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Patterns of Care in Elderly Head-and-Neck Cancer Radiation Oncology Patients: A Single-Center Cohort Study

Purpose: To compare the patterns of care for elderly head-and-neck cancer patients with those of younger patients. Methods and Materials: A retrospective review was conducted of all new mucosal head-and-neck cancer referrals to radiation oncology between July 1, 2003 and December 31, 2007 at our institution. The clinical characteristics, treatment pattern, tolerance, and outcomes were compared between the elderly (aged {>=}75 years) and younger (aged <75 years) cohorts. Results: A total of 2,312 patients, including 452 (20%) elderly and 1,860 (80%) younger patients, were studied. The elderly patients were more likely to be women (36% vs. 27%, p <.01) and to have other malignancies (23% vs. 13%, p <.01), Stage I or II disease (38% vs. 32%, p <.01), and N0 status (56% vs. 42%, p <.01). Treatment was less often curative in intent (79% vs. 93%, p <.01). For the 1,487 patients who received definitive radiotherapy (RT), no differences were found between the elderly (n = 238) and younger (n = 1,249) patients in treatment interruption, completion, or treatment-related death. Within the subset of 760 patients who received intensified treatment (concurrent chemoradiotherapy or hyperfractionated accelerated RT), no difference was seen between the elderly (n = 46) and younger (n = 714) patients in treatment interruption, completion, or treatment-related death. After a median follow-up of 2.5 years, the 2-year cause-specific survival rate after definitive RT was 72% (range, 65-78%) for the elderly vs. 86% (range, 84-88%) for the younger patients (p <.01). Conclusion: Elderly head-and-neck cancer patients exhibited different clinical characteristics and experienced different patterns of care from younger patients. Although age itself was an adverse predictor of cause-specific survival, its effect was modest. Elderly patients selected for definitive RT or intensified RT showed no evidence of impaired treatment tolerance.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Proton Radiotherapy for Pediatric Central Nervous System Germ Cell Tumors: Early Clinical Outcomes

Purpose: To report early clinical outcomes for children with central nervous system (CNS) germ cell tumors treated with protons; to compare dose distributions for intensity-modulated photon radiotherapy (IMRT), three-dimensional conformal proton radiation (3D-CPT), and intensity-modulated proton therapy with pencil beam scanning (IMPT) for whole-ventricular irradiation with and without an involved-field boost. Methods and Materials: All children with CNS germinoma or nongerminomatous germ cell tumor who received treatment at the Massachusetts General Hospital between 1998 and 2007 were included in this study. The IMRT, 3D-CPT, and IMPT plans were generated and compared for a representative case. Results: Twenty-two patients were treated with 3D-CPT. At a median follow-up of 28 months, there were no CNS recurrences; 1 patient had a recurrence outside the CNS. Local control, progression-free survival, and overall survival rates were 100%, 95%, and 100%, respectively. Comparable tumor volume coverage was achieved with IMRT, 3D-CPT, and IMPT. Substantial normal tissue sparing was seen with any form of proton therapy as compared with IMRT. The use of IMPT may yield additional sparing of the brain and temporal lobes. Conclusions: Preliminary disease control with proton therapy compares favorably to the literature. Dosimetric comparisons demonstrate the advantage of proton radiation over IMRT for whole-ventricle radiation. Superior dose distributions were accomplished with fewer beam angles utilizing 3D-CPT and scanned protons. Intensity-modulated proton therapy with pencil beam scanning may improve dose distribution as compared with 3D-CPT for this treatment.

62 RADIOLOGY AND NUCLEAR MEDICINE↗