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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Concurrent Flame Growth, Spread and Extinction over Composite Fabric Samples in Low Speed Purely Forced Flow in Microgravity

As a part of the NASA BASS and BASS-II experimental projects aboard the International Space Station, flame growth, spread and extinction over a composite cotton-fiberglass fabric blend (referred to as the SIBAL fabric) were studied in low-speed concurrent forced flows. The tests were conducted in a small flow duct within the Microgravity Science Glovebox. The fuel samples measured 1.2 and 2.2 cm wide and 10 cm long. Ambient oxygen was varied from 21% down to 16% and flow speed from 40 cm/s down to 1 cm/s. A small flame resulted at low flow, enabling us to observe the entire history of flame development including ignition, flame growth, steady spread (in some cases) and decay at the end of the sample. In addition, by decreasing flow velocity during some of the tests, low-speed flame quenching extinction limits were found as a function of oxygen percentage. The quenching speeds were found to be between 1 and 5 cm/s with higher speed in lower oxygen atmosphere. The shape of the quenching boundary supports the prediction by earlier theoretical models. These long duration microgravity experiments provide a rare opportunity for solid fuel combustion since microgravity time in ground-based facilities is generally not sufficient. This is the first time that a low-speed quenching boundary in concurrent spread is determined in a clean and unambiguous manner.

concurrent↗
NASA NTRS2015

Model-Based Systems Engineering in Concurrent Engineering Centers

Concurrent Engineering Centers (CECs) are specialized facilities with a goal of generating and maturing engineering designs by enabling rapid design iterations. This is accomplished by co-locating a team of experts (either physically or virtually) in a room with a focused design goal and a limited timeline of a week or less. The systems engineer uses a model of the system to capture the relevant interfaces and manage the overall architecture. A single model that integrates other design information and modeling allows the entire team to visualize the concurrent activity and identify conflicts more efficiently, potentially resulting in a systems model that will continue to be used throughout the project lifecycle. Performing systems engineering using such a system model is the definition of model-based systems engineering (MBSE); therefore, CECs evolving their approach to incorporate advances in MBSE are more successful in reducing time and cost needed to meet study goals. This paper surveys space mission CECs that are in the middle of this evolution, and the authors share their experiences in order to promote discussion within the community.

systems engineering↗
NASA NTRS2015

Model-Based Systems Engineering in Concurrent Engineering Centers

Concurrent Engineering Centers (CECs) are specialized facilities with a goal of generating and maturing engineering designs by enabling rapid design iterations. This is accomplished by co-locating a team of experts (either physically or virtually) in a room with a narrow design goal and a limited timeline of a week or less. The systems engineer uses a model of the system to capture the relevant interfaces and manage the overall architecture. A single model that integrates other design information and modeling allows the entire team to visualize the concurrent activity and identify conflicts more efficiently, potentially resulting in a systems model that will continue to be used throughout the project lifecycle. Performing systems engineering using such a system model is the definition of model-based systems engineering (MBSE); therefore, CECs evolving their approach to incorporate advances in MBSE are more successful in reducing time and cost needed to meet study goals. This paper surveys space mission CECs that are in the middle of this evolution, and the authors share their experiences in order to promote discussion within the community.

MODEL↗
NASA NTRS2020

Integrated Concurrent Engineering Teams for Increased Efficiency in Flight Projects

A highly integrated Concurrent Engineering Team (CET) within a flight project evolves in its function and has the potential to provide many benefits through the project lifecycle. The benefits include superior systems-oriented design products, as well as overall improved project efficiency and higher-performing interpersonal relationships within the project. If physically integrated, this can manifest as a Concurrent Engineering Center (CEC) centrally located within a project’s physical office space. Here we discuss the process to establish and maintain a tightly integrated engineering and design team for providing highly streamlined service to the project, including a cost/benefits analysis discussion.

Flight Project↗
NASA NTRS2020

Integrated Concurrent Engineering Teams for Increased Efficiency in Flight Projects

A highly integrated Concurrent Engineering Team (CET) within a flight project evolves in its function and has the potential to provide many benefits through the project lifecycle. The benefits include superior systems-oriented design products, as well as overall improved project efficiency and higher-performing interpersonal relationships within the project. If physically integrated, this can manifest as a Concurrent Engineering Center (CEC) centrally located within a project’s physical office space. Here we discuss the process to establish and maintain a tightly integrated engineering and design team for providing highly streamlined service to the project, including a cost/benefits analysis discussion.

Flight Project↗
DOE OSTI2016

Critical Points Based Register-Concurrency Autotuning for GPUs

The unprecedented prevalence of GPGPU is largely attributed to its abundant on-chip register resources, which allow massively concurrent threads and extremely fast context switch. However, due to internal memory capacity constraints, there is a tradeoff between the per-thread register usage and the overall concurrency. This becomes a design problem in terms of performance tuning, since the performance “sweet spot” which can be significantly affected by these two factors is generally unknown beforehand. In this paper, we propose an effective autotuning solution to quickly and efficiently select the optimal number of registers perthread for delivering the best GPU performance. Experiments on three generations of GPUs (Nvidia Fermi, Kepler and Maxwell) demonstrate that our simple strategy can achieve an average of 10% performance improvement while a max of 50% over the original version without modifying the user program. Additionally, to reduce local cache misses due to register spilling and further improve performance, we explore three optimization schemes (i.e. bypass L1 for global memory access, enlarge local L1 cache and spill into shared memory) and discuss their impact on performance on a Kepler GPU.

auto-tuning↗
DOE OSTI2017

Concurrent Synthesis of High-Performance Monolayer Transition Metal Disulfides

To date, the chemical vapor deposition (CVD) approach has been widely used for the growth of transition metal dichalcogenides (TMDs). However, the reported CVD methods to synthesize TMDs cannot be used to grow more than one type of TMDs. This work reports a promising CVD technique to concurrently synthesize multiple monolayer transition metal disulfides once. The optoelectrical characterization and high-resolution transmission electron microscopy show the high quality of monolayer crystals, and, more importantly, there is no mixing between different precursors during the growth process, which has been investigated by considering the gas flow dynamics and concentration distribution of precursors in our setup. This strategy indicates the promising future for the batch production of 2D materials and the concurrent synthesis techniques in standard state-of-the-art complementary metal-oxide-semiconductor (CMOS) fabrication technology.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Concurrent multiscale modeling of microstructural effects on localization behavior in finite deformation solid mechanics

The heterogeneity in mechanical fields introduced by microstructure plays a critical role in the localization of deformation. In order to resolve this incipient stage of failure, it is therefore necessary to incorporate microstructure with sufficient resolution. On the other hand, computational limitations make it infeasible to represent the microstructure in the entire domain at the component scale. Here, the authors demonstrate the use of concurrent multiscale modeling to incorporate explicit, finely resolved microstructure in a critical region while resolving the smoother mechanical fields outside this region with a coarser discretization to limit computational cost. The microstructural physics is modeled with a high-fidelity model that incorporates anisotropic crystal elasticity and rate-dependent crystal plasticity to simulate the behavior of a stainless steel alloy. The component-scale material behavior is treated with a lower fidelity model incorporating isotropic linear elasticity and rate-independent J 2 plasticity. The microstructural and component scale subdomains are modeled concurrently, with coupling via the Schwarz alternating method, which solves boundary-value problems in each subdomain separately and transfers solution information between subdomains via Dirichlet boundary conditions. In this study, the framework is applied to model incipient localization in tensile specimens during necking.

36 MATERIALS SCIENCE↗
DOE OSTI2019

A new apparatus for the concurrent measurement of friction and permeability evolution in fault gouge

Here we introduce a new miniature double direct shear (mini-DDS) apparatus, housed within a standard-triaxial (TEMCO) pressure vessel, capable of concurrently measuring the evolution of frictional strength, stability, healing and along-fault permeability under in situ conditions of stress and temperature. The apparatus accommodates gouge samples (25 mm × 32 mm) and intact rock samples with confining and shear stresses and pore pressures up to ~26 MPa. Permeability may be measured with applied flow rates ranging from 1.67 × 10 -11 to 3.6 × 10 -6 m 3 /s to a flow accuracy of 0.5% representing a lower bound of permeability >2.2 × 10 -18 m 2 . Sliding velocities are in the range 0.1 μm/s to 0.67 cm/s with a frame stiffness of 0.067 kN/μm. We describe protocols and procedures for calibration and experiments and note the potential of the apparatus for both rapid and extended-duration measurements of friction-permeability evolution and healing. The apparatus returns measurements of friction and stability of reference materials of F110 quartz consistent with the literature while additionally allowing the concurrent measurement of permeability. Permeability of F110 quartz evolves in slide-hold-slide (SHS) experiments with increases during holds and decreases during subsequent slides. These observations are consistent with grain crushing and resultant wear products that reduce that permeability by clogging during slides with unclogging of the major fluid channels occurring during shearing.

58 GEOSCIENCES↗
DOE OSTI2013

Patterns of Failure After Concurrent Bevacizumab and Hypofractionated Stereotactic Radiation Therapy for Recurrent High-Grade Glioma

Purpose: Concurrent bevacizumab with hypofractionated stereotactic radiation therapy (HSRT) is safe and effective for the treatment of recurrent high-grade gliomas (HGG). The objective of this study was to characterize the patterns of failure after this treatment regimen. Methods and Materials: Twenty-four patients with recurrent enhancing HGG were previously treated on an institutional review board-approved protocol of concurrent bevacizumab and reirradiation. Patients received 30 Gy in 5 fractions to the recurrent tumor with HSRT. Brain magnetic resonance imaging (MRI) was performed every 2 cycles, and bevacizumab was continued until clinical or radiographic tumor progression according to the criteria of Macdonald et al. MRI at the time of progression was fused to the HSRT treatment plan, and the location of recurrence was classified on the basis of volume within the 95% isodose line. Outcomes based on patient characteristics, tumor grade, recurrence pattern, and best response to treatment were analyzed by the Kaplan-Meier method. Results: Twenty-two patients experienced either clinical or radiographic progression. Recurrent tumor was enhancing in 15 (71.4%) and nonenhancing in 6 (28.6%) patients. Eleven patients (52.4%) had recurrence within the radiation field, 5 patients (23.8%) had marginal recurrence, and 5 patients had recurrence outside the radiation field. Pattern of enhancement and location of failure did not correlate with overall survival or progression-free survival. Radiographic response was the only variable to significantly correlate with progression-free survival. Conclusions: Despite the promising initial response seen with the addition of HSRT to bevacizumab as salvage treatment for recurrent HGG, approximately half of patients ultimately still experience failure within the radiation field. The rate of local failure with the addition of HSRT seems to be lower than that seen with bevacizumab alone in the salvage setting. Our data underscore the radioresistance of HGG and the need for better salvage treatments.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Prognostic Significance of Carbohydrate Antigen 19-9 in Unresectable Locally Advanced Pancreatic Cancer Treated With Dose-Escalated Intensity Modulated Radiation Therapy and Concurrent Full-Dose Gemcitabine: Analysis of a Prospective Phase 1/2 Dose Escalation Study

Purpose: Although established in the postresection setting, the prognostic value of carbohydrate antigen 19-9 (CA19-9) in unresectable locally advanced pancreatic cancer (LAPC) is less clear. We examined the prognostic utility of CA19-9 in patients with unresectable LAPC treated on a prospective trial of intensity modulated radiation therapy (IMRT) dose escalation with concurrent gemcitabine. Methods and Materials: Forty-six patients with unresectable LAPC were treated at the University of Michigan on a phase 1/2 trial of IMRT dose escalation with concurrent gemcitabine. CA19-9 was obtained at baseline and during routine follow-up. Cox models were used to assess the effect of baseline factors on freedom from local progression (FFLP), distant progression (FFDP), progression-free survival (PFS), and overall survival (OS). Stepwise forward regression was used to build multivariate predictive models for each endpoint. Results: Thirty-eight patients were eligible for the present analysis. On univariate analysis, baseline CA19-9 and age predicted OS, CA19-9 at baseline and 3 months predicted PFS, gross tumor volume (GTV) and black race predicted FFLP, and CA19-9 at 3 months predicted FFDP. On stepwise multivariate regression modeling, baseline CA19-9, age, and female sex predicted OS; baseline CA19-9 and female sex predicted both PFS and FFDP; and GTV predicted FFLP. Patients with baseline CA19-9 ≤90 U/mL had improved OS (median 23.0 vs 11.1 months, HR 2.88, P<.01) and PFS (14.4 vs 7.0 months, HR 3.61, P=.001). CA19-9 progression over 90 U/mL was prognostic for both OS (HR 3.65, P=.001) and PFS (HR 3.04, P=.001), and it was a stronger predictor of death than either local progression (HR 1.46, P=.42) or distant progression (HR 3.31, P=.004). Conclusions: In patients with unresectable LAPC undergoing definitive chemoradiation therapy, baseline CA19-9 was independently prognostic even after established prognostic factors were controlled for, whereas CA19-9 progression strongly predicted disease progression and death. Future trials should stratify by baseline CA19-9 and incorporate CA19-9 progression as a criterion for progressive disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Alignment Focus of Daily Image Guidance for Concurrent Treatment of Prostate and Pelvic Lymph Nodes

Purpose: To determine the dosimetric impact of daily imaging alignment focus on the prostate soft tissue versus the pelvic bones for the concurrent treatment of the prostate and pelvic lymph nodes (PLN) and to assess whether multileaf collimator (MLC) tracking or adaptive planning (ART) is necessary with the current clinical planning margins of 8 mm/6 mm posterior to the prostate and 5 mm to the PLN. Methods and Materials: A total of 124 kilovoltage cone-beam computed tomography (kV-CBCT) images from 6 patients were studied. For each KV-CBCT, 4 plans were retrospectively created using an isocenter shifting method with 2 different alignment focuses (prostate, PLN), an MLC shifting method, and the ART method. The selected dosimetric endpoints were compared among these plans. Results: For the isoshift contour, isoshift bone, MLC shift, and ART plans, D99 of the prostate was ≥97% of the prescription dose in 97.6%, 73.4%, 98.4%, and 96.8% of 124 fractions, respectively. Accordingly, D99 of the PLN was ≥97% of the prescription dose in 98.4%, 98.4%, 98.4%, and 100% of 124 fractions, respectively. For the rectum, D5 exceeded 105% of the planned D5 (and D5 of ART plans) in 11% (4%), 10% (2%), and 13% (5%) of 124 fractions, respectively. For the bladder, D5 exceeded 105% of the planned D5 (and D5 of ART) plans in 0% (2%), 0% (2%), and 0% (1%) of 124 fractions, respectively. Conclusion: For concurrent treatment of the prostate and PLN, with a planning margin to the prostate of 8 mm/6 mm posterior and a planning margin of 5 mm to the PLN, aligning to the prostate soft tissue can achieve adequate dose coverage to the both target volumes; aligning to the pelvic bone would result in underdosing to the prostate in one-third of fractions. With these planning margins, MLC tracking and ART methods have no dosimetric advantages.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Impact of Weight Change During the Course of Concurrent Chemoradiation Therapy on Outcomes in Stage IIIB Non-Small Cell Lung Cancer Patients: Retrospective Analysis of 425 Patients

Purpose: We retrospectively investigated the impact of weight change (WC) during concurrent chemoradiation therapy (C-CRT) on clinical outcomes of stage 3B non-small cell lung cancer (NSCLC) patients. Methods and Materials: A total of 425 patients treated with C-CRT were included. All patients received 60 to 66 Gy of thoracic radiation therapy concurrently with 1 to 3 cycles of platinum-based chemotherapy. Pre- and posttreatment weight measurements on first and last days of C-CRT were used for WC. Patients were divided into 2 groups: group 1 = weight loss (WL); group 2 = weight preservation/gain (WP) for comparative analyses. Results: Following C-CRT, 252 patients (59.3%) experienced WL, while 89 patients (20.9%) and 84 patients (19.8%) showed WP or WG. At median 24.2 months of follow-up, 142 patients (33.4%) were alive (84 WP [48.6%] and 58 WL [23.0%]), and 58 (13.6%) of them were free of disease progression (41 [23.7%] for WP and 17 [6.7%] for WL). Median overall survival (OS), locoregional progression-free survival (LRPFS), progression-free survival (PFS), and distant metastases-free survival (DMFS) for the entire population were 22.8, 14.4, 10.6, and 11.7 months, respectively. Intergroup comparisons between WP and WL cohorts revealed significantly superior OS, LRPFS, PFS, and DMFS in WP patients (P<.05 for each). On multivariate analyses, only WL and advanced T stage were associated with poor prognosis (P<.05). Conclusions: Present results in 425 stage 3B NSCLC patients demonstrated that WL during C-CRT is strongly associated with inferior survival outcomes compared to WP. This emerging finding might be useful by forming an encouraging basis for future investigations in facilitating a way to improve the outcomes of these patients experiencing WL during C-CRT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Administration of Concurrent Vaginal Brachytherapy During Chemotherapy for Treatment of Endometrial Cancer

Purpose: To evaluate the tolerability and toxicity of administering vaginal brachytherapy (VB) concurrently during chemotherapy compared with the sequential approach for patients with endometrial cancer. Methods and Materials: A retrospective analysis of 372 surgically staged patients with endometrial cancer American Joint Committee on Cancer 2009 stages I to IV treated with adjuvant postoperative radiation therapy (RT) at our institution from 2001 to 2012 was conducted. All patients received VB + external beam RT (EBRT) + 6 cycles of adjuvant carboplatin- and paclitaxel-based chemotherapy. The VB mean dose was 15.08 Gy (range, 15-20 Gy), with 3 to 4 weekly applications, and the EBRT mean dose was 45 Gy delivered with 3-dimensional or intensity modulated RT techniques. Hematologic, gastrointestinal (GI), and genitourinary (GU) toxicities were assessed by Common Toxicity Criteria (CTC) and compared between sequential and concurrent chemotherapy and VB schedules. Results: Among patients who received RT and adjuvant chemotherapy, 180 of 372 patients (48%) received RT sandwiched between cycles 3 and 4 of chemotherapy. A separate group of 192 patients (52%) were treated with VB during the first 3 cycles of chemotherapy, with a weekly application on nonchemotherapy days, and received the EBRT portion in a sandwiched fashion. Patients treated with VB during chemotherapy had a decreased overall treatment time by 4 weeks (P<.001; 95% confidence interval: 3.99-4.02) and sustained no difference in CTC-graded acute hematologic, GI, or GU toxicities in comparison with the patients treated with VB and chemotherapy in a sequential manner (P>.05). CTC grade 3 or 4 hematologic, GI, and GU toxicities were zero. Conclusions: VB during chemotherapy is well tolerated, decreases overall treatment time, and does not render more toxicity than the sequential regimen.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

A Phase 2 Trial of Radiation Therapy With Concurrent Paclitaxel Chemotherapy After Surgery in Patients With High-Risk Endometrial Cancer: A Korean Gynecologic Oncologic Group Study

Purpose: A phase 2 study was completed by the Korean Gynecologic Oncologic Group to evaluate the efficacy and toxicity of concurrent chemoradiation with weekly paclitaxel in patients with high-risk endometrial cancer. Methods and Materials: Pathologic requirements included endometrial endometrioid adenocarcinoma stages III and IV. Radiation therapy consisted of a total dose of 4500 to 5040 cGy in 5 fractions per week for 6 weeks. Paclitaxel 60 mg/m{sup 2} was administered once weekly for 5 weeks during radiation therapy. Results: Fifty-seven patients were enrolled between January 2006 and March 2008. The median follow-up time was 60.0 months (95% confidence interval [CI], 51.0-58.2). All grade 3/4 toxicities were hematologic and usually self-limited. There was no life-threatening toxicity. The cumulative incidence of intrapelvic recurrence sites was 1.9% (1/52), and the cumulative incidence of extrapelvic recurrence sites was 34.6% (18/52). The estimated 5-year disease-free and overall survival rates were 63.5% (95% CI, 50.4-76.5) and 82.7% (95% CI, 72.4-92.9), respectively. Conclusions: Concurrent chemoradiation with weekly paclitaxel is well tolerated and seems to be effective for high-risk endometrioid endometrial cancers. This approach appears reasonable to be tested for efficacy in a prospective, randomized controlled study.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Phase 2 Study of Concurrent Cetuximab Plus Definitive Thoracic Radiation Therapy Followed by Consolidation Docetaxel Plus Cetuximab in Poor Prognosis or Elderly Patients With Locally Advanced Non-Small Cell Lung Cancer

Background: Recursive partitioning analysis has shown that Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≥2, male sex, and age ≥70 years are prognostic of poor outcome in locally advanced non-small cell lung cancer (LA-NSCLC) patients. Concurrent chemoradiation therapy (CRT) improves survival, but toxicity is a concern in this frail patient cohort. We therefore opened this trial of concurrent definitive thoracic radiation therapy (XRT) and cetuximab, followed by consolidation docetaxel plus cetuximab. Methods and Materials: Eligible patients had pathologically proven, unresectable LA-NSCLC (stage IIA-“dry” IIIB). They had ECOG PS 2 or weight loss ≥5% in 3 months or were aged ≥70 years. The primary objective was progression-free survival (PFS). Secondary objectives included overall survival (OS) and overall response rate (ORR). Results: From May 2008 to November 2010, a total of 32 patients were evaluated in our single-institution, institutional review board–approved prospective clinical trial. Three patients were screen failures and 2 more withdrew consent before treatment, leaving 27 evaluable patients. One was removed because of poor therapy compliance, and 2 were taken off trial because of grade 3 cetuximab-related toxicities but were followed up under intent-to-treat analysis. The median follow-up and OS were 10.5 months. The median PFS was 7.5 months. The ORR was 59.3%. Eight early/sudden deaths were reported. Upon review, 6 patients developed severe pulmonary complications. Conclusions: Patients enrolled in this trial had improved OS compared with poor-PS historical controls (10.5 vs 6.4 months) and comparable OS to good-PS historical controls (10.5 vs 11.9 months) treated with XRT alone. However, pulmonary toxicity is a concern. Consolidative cetuximab/docetaxel, in conjunction with high-dose radiation therapy, is a putative cause.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Phase 2 Study of Accelerated Hypofractionated Thoracic Radiation Therapy and Concurrent Chemotherapy in Patients With Limited-Stage Small-Cell Lung Cancer

Purpose: To prospectively investigate the efficacy and toxicity of accelerated hypofractionated thoracic radiation therapy (HypoTRT) combined with concurrent chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC), with the hypothesis that both high radiation dose and short radiation time are important in this setting. Methods and Materials: Patients with previously untreated LS-SCLC, Eastern Cooperative Oncology Group performance status of 0 to 2, and adequate organ function were eligible. HypoTRT of 55 Gy at 2.5 Gy per fraction over 30 days was given on the first day of the second or third cycle of chemotherapy. An etoposide/cisplatin regimen was given to 4 to 6 cycles. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 2-year progression-free survival rate. Results: Fifty-nine patients were enrolled from July 2007 through February 2012 (median age, 58 years; 86% male). The 2-year progression-free survival rate was 49.0% (95% confidence interval [CI] 35.3%-62.7%). Median survival time was 28.5 months (95% CI 9.0-48.0 months); the 2-year overall survival rate was 58.2% (95% CI 44.5%-71.9%). The 2-year local control rate was 76.4% (95% CI 63.7%-89.1%). The severe hematologic toxicities (grade 3 or 4) were leukopenia (32%), neutropenia (25%), and thrombocytopenia (15%). Acute esophagitis and pneumonitis of grade ≥3 occurred in 25% and 10% of the patients, respectively. Thirty-eight patients (64%) received prophylactic cranial irradiation. Conclusion: Our study showed that HypoTRT of 55 Gy at 2.5 Gy per fraction daily concurrently with etoposide/cisplatin chemotherapy has favorable survival and acceptable toxicity. This radiation schedule deserves further investigation in LS-SCLC.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Phase 2 Study of Docetaxel, Cisplatin, and Concurrent Radiation for Technically Resectable Stage III-IV Squamous Cell Carcinoma of the Head and Neck

Purpose: We investigated the efficacy and safety of weekly low-dose docetaxel and cisplatin therapy concurrent with conventionally fractionated radiation in patients with technically resectable stage III-IV squamous cell carcinoma of the head and neck. Methods and Materials: Between March 2004 and October 2011, we enrolled 117 patients, of whom 116 were analyzable (43 had oropharyngeal cancer, 54 had hypopharyngeal cancer, and 19 had laryngeal cancer), and 85 (73%) had stage IV disease. Radiation consisted of 66 Gy in 33 fractions. Docetaxel, 10 mg/m{sup 2}, followed by cisplatin, 20 mg/m{sup 2}, administered on the same day were given once a week for 6 cycles. The primary endpoint was overall complete response (CR) rate after chemoradiation therapy. Human papillomavirus (HPV) DNA in oropharyngeal cancer was examined by PCR. Results: Of 116 patients, 82 (71%) completed treatment per protocol; 102 (88%) received the full radiation therapy dose; and 90 (78%) and 12 (10%) patients received 6 and 5 chemotherapy cycles, respectively. Overall CR rate was 71%. After median follow-up of 50.9 months (range: 15.6-113.9 months for surviving patients), 2-year and 4-year overall survival rates were 82% and 68%, respectively. Cumulative 2-year and 4-year local failure rates were 27% and 28%, respectively, whereas distant metastasis rates were 15% and 22%, respectively. HPV status in oropharyngeal cancer was not associated with treatment efficacy. Acute toxicity included grade 3 and 4 in-field mucositis in 73% and 5% of patients, respectively, whereas myelosuppression and renal injury were minimal. No patients died of toxicity. Feeding tube dependence in 8% and tracheostomy in 1% of patients were evident at 2 years postchemoradiation therapy in patients who survived without local treatment failure. Conclusions: Local control and survival with this regimen were satisfactory. Although acute toxicity, such as mucositis, was common, late toxicity, such as laryngoesophageal dysfunction, was minimal. Therapy using weekly low-dose docetaxel and cisplatin concurrent with radiation warrants further evaluation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗