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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 757 records · Page 42
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Definitive Primary Therapy in Patients Presenting With Oligometastatic Non-Small Cell Lung Cancer

Purpose: Although palliative chemotherapy is the standard of care for patients with diagnoses of stage IV non-small cell lung cancer (NSCLC), patients with a small metastatic burden, “oligometastatic” disease, may benefit from more aggressive local therapy. Methods and Materials: We identified 186 patients (26% of stage IV patients) prospectively enrolled in our institutional database from 2002 to 2012 with oligometastatic disease, which we defined as 5 or fewer distant metastatic lesions at diagnosis. Univariate and multivariable Cox proportional hazards models were used to identify patient and disease factors associated with improved survival. Using propensity score methods, we investigated the effect of definitive local therapy to the primary tumor on overall survival. Results: Median age at diagnosis was 61 years of age; 51% of patients were female; 12% had squamous histology; and 33% had N0-1 disease. On multivariable analysis, Eastern Cooperate Oncology Group performance status ≥2 (hazard ratio [HR], 2.43), nodal status, N2-3 (HR, 2.16), squamous pathology, and metastases to multiple organs (HR, 2.11) were associated with a greater hazard of death (all P<.01). The number of metastatic lesions and radiologic size of the primary tumor were not significantly associated with overall survival. Definitive local therapy to the primary tumor was associated with prolonged survival (HR, 0.65, P=.043). Conclusions: Definitive local therapy to the primary tumor appears to be associated with improved survival in patients with oligometastatic NSCLC. Select patient and tumor characteristics, including good performance status, nonsquamous histology, and limited nodal disease, may predict for improved survival in these patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Genomic Prostate Cancer Classifier Predicts Biochemical Failure and Metastases in Patients After Postoperative Radiation Therapy

Purpose: To test the hypothesis that a genomic classifier (GC) would predict biochemical failure (BF) and distant metastasis (DM) in men receiving radiation therapy (RT) after radical prostatectomy (RP). Methods and Materials: Among patients who underwent post-RP RT, 139 were identified for pT3 or positive margin, who did not receive neoadjuvant hormones and had paraffin-embedded specimens. Ribonucleic acid was extracted from the highest Gleason grade focus and applied to a high-density-oligonucleotide microarray. Receiver operating characteristic, calibration, cumulative incidence, and Cox regression analyses were performed to assess GC performance for predicting BF and DM after post-RP RT in comparison with clinical nomograms. Results: The area under the receiver operating characteristic curve of the Stephenson model was 0.70 for both BF and DM, with addition of GC significantly improving area under the receiver operating characteristic curve to 0.78 and 0.80, respectively. Stratified by GC risk groups, 8-year cumulative incidence was 21%, 48%, and 81% for BF (P<.0001) and for DM was 0, 12%, and 17% (P=.032) for low, intermediate, and high GC, respectively. In multivariable analysis, patients with high GC had a hazard ratio of 8.1 and 14.3 for BF and DM. In patients with intermediate or high GC, those irradiated with undetectable prostate-specific antigen (PSA ≤0.2 ng/mL) had median BF survival of >8 years, compared with <4 years for patients with detectable PSA (>0.2 ng/mL) before initiation of RT. At 8 years, the DM cumulative incidence for patients with high GC and RT with undetectable PSA was 3%, compared with 23% with detectable PSA (P=.03). No outcome differences were observed for low GC between the treatment groups. Conclusion: The GC predicted BF and metastasis after post-RP irradiation. Patients with lower GC risk may benefit from delayed RT, as opposed to those with higher GC; however, this needs prospective validation. Genomic-based models may be useful for improved decision-making for treatment of high-risk prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Adoption of Hypofractionated Radiation Therapy for Breast Cancer After Publication of Randomized Trials

Purpose: Large randomized trials have established the noninferiority of shorter courses of “hypofractionated” radiation therapy (RT) to the whole breast compared to conventional courses using smaller daily doses in the adjuvant treatment of selected breast cancer patients undergoing lumpectomy. Hypofractionation is more convenient and less costly. Therefore, we sought to determine uptake of hypofractionated breast RT over time. Methods and Materials: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database, we identified 16,096 women with node-negative breast cancer and 4269 with ductal carcinoma in situ (DCIS) who received lumpectomy followed by more than 12 fractions of RT between 2004 and 2010. Based on Medicare claims, we determined the number of RT treatments given and grouped patients into those receiving hypofractionation (13-24) or those receiving conventional fractionation (≥25). We also determined RT technique (intensity modulated RT or not) using Medicare claims. We evaluated patterns and correlates of hypofractionation receipt using bivariate and multivariable analyses. Results: Hypofractionation use was similar in patients with DCIS and those with invasive disease. Overall, the use of hypofractionation increased from 3.8% in 2006 to 5.4% in 2007, to 9.4% in 2008, and to 13.6% in 2009 and 2010. Multivariable analysis showed increased use of hypofractionation in recent years and in patients with older age, smaller tumors, increased comorbidity, higher regional education, and Western SEER regions. However, even in patients over the age of 80, the hypofractionation rate in 2009 to 2010 was only 25%. Use of intensity modulated RT (IMRT) also increased over time (from 9.4% in 2004 to 22.7% in 2009-2010) and did not vary significantly between patients receiving hypofractionation and those receiving traditional fractionation. Conclusions: Hypofractionation use increased among low-risk older US breast cancer patients with publication and maturation of evidence from randomized trials, but overall use of this cost-saving approach remained low. This contrasts with the more rapid rate of adoption of IMRT in the same time period, a costly innovation supported by less strong evidence of benefit.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Molecular Imaging Biomarkers of Resistance to Radiation Therapy for Spontaneous Nasal Tumors in Canines

Purpose: Imaging biomarkers of resistance to radiation therapy can inform and guide treatment management. Most studies have so far focused on assessing a single imaging biomarker. The goal of this study was to explore a number of different molecular imaging biomarkers as surrogates of resistance to radiation therapy. Methods and Materials: Twenty-two canine patients with spontaneous sinonasal tumors were treated with accelerated hypofractionated radiation therapy, receiving either 10 fractions of 4.2 Gy each or 10 fractions of 5.0 Gy each to the gross tumor volume. Patients underwent fluorodeoxyglucose (FDG)-, fluorothymidine (FLT)-, and Cu(II)-diacetyl-bis(N4-methylthiosemicarbazone) (Cu-ATSM)-labeled positron emission tomography/computed tomography (PET/CT) imaging before therapy and FLT and Cu-ATSM PET/CT imaging during therapy. In addition to conventional maximum and mean standardized uptake values (SUV{sub max}; SUV{sub mean}) measurements, imaging metrics providing response and spatiotemporal information were extracted for each patient. Progression-free survival was assessed according to response evaluation criteria in solid tumor. The prognostic value of each imaging biomarker was evaluated using univariable Cox proportional hazards regression. Multivariable analysis was also performed but was restricted to 2 predictor variables due to the limited number of patients. The best bivariable model was selected according to pseudo-R{sup 2}. Results: The following variables were significantly associated with poor clinical outcome following radiation therapy according to univariable analysis: tumor volume (P=.011), midtreatment FLT SUV{sub mean} (P=.018), and midtreatment FLT SUV{sub max} (P=.006). Large decreases in FLT SUV{sub mean} from pretreatment to midtreatment were associated with worse clinical outcome (P=.013). In the bivariable model, the best 2-variable combination for predicting poor outcome was high midtreatment FLT SUV{sub max} (P=.022) in combination with large FLT response from pretreatment to midtreatment (P=.041). Conclusions: In addition to tumor volume, pronounced tumor proliferative response quantified using FLT PET, especially when associated with high residual FLT PET at midtreatment, is a negative prognostic biomarker of outcome in canine tumors following radiation therapy. Neither FDG PET nor Cu-ATSM PET were predictive of outcome.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Long-Term Outcomes and Patterns of Relapse of Early-Stage Extranodal Marginal Zone Lymphoma Treated With Radiation Therapy With Curative Intent

Purpose: To report the long-term outcome and patterns of relapse of a large cohort of marginal zone lymphoma (MZL) patients treated with curative-intent radiation therapy (RT) alone. Patients and Methods: We reviewed the charts of 490 consecutive patients with stage IE or IIE MZL referred between 1992 and 2012 to our institution. Of those, 244 patients (50%) were treated with RT alone. Pathology was confirmed by hematopathologists at our institution. Patient and disease factors were analyzed for association with relapse-free survival (RFS) and overall survival (OS). Results: Median age of the cohort was 59 years, and median follow-up was 5.2 years. Ann Arbor stage was IE in 92%. Most common disease sites were stomach (50%), orbit (18%), non-thyroid head-and-neck (8%), skin (8%), and breast (5%). Median RT dose was 30 Gy. Five-year OS and RFS were 92% and 74%, respectively. Cumulative incidence of disease-specific death was just 1.1% by 5 years. Sixty patients (24%) developed relapse of disease; 10 were in the RT field. Crude rate of transformation to pathologically confirmed large-cell lymphoma was 1.6%. On multivariable analysis, primary disease site (P=.007) was independently associated with RFS, along with age (P=.04), presence of B-symptoms (P=.02), and International Prognostic Index risk group (P=.03). All disease sites except for head-and-neck had worse RFS relative to stomach. Conclusion: Overall and cause-specific survival are high in early-stage extra-nodal MZL treated with curative RT alone. In this large cohort of 244 patients, most patients did not experience relapse of MZL after curative RT; when relapses did occur, the majority were in distant sites. Stomach cases were less likely to relapse than other anatomic sites. Transformation to large-cell lymphoma was rare.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Long-Term Efficacy and Toxicity of Low-Dose-Rate {sup 125}I Prostate Brachytherapy as Monotherapy in Low-, Intermediate-, and High-Risk Prostate Cancer

Purpose/Objectives: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with low-dose-rate prostate brachytherapy permanent implant (PI) monotherapy. Methods and Materials: From 1996 to 2007, 1989 patients with low-risk (61.3%), intermediate-risk (29.8%), high-intermediate-risk (4.5%), and high-risk prostate cancer (4.4%) were treated with PI and followed up prospectively in a registry. All patients were treated with {sup 125}I monotherapy to 144 Gy. Late toxicity was coded retrospectively according to a modified Common Terminology Criteria for Adverse Events 4.0 scale. The rates of biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), overall survival (OS), and prostate cancer–specific mortality (PCSM) were calculated. We identified factors associated with late grade ≥3 genitourinary (GU) and gastrointestinal (GI) toxicity, bRFS, DMFS, OS, PCSM, and incontinence. Results: The median age of the patients was 67 years, and the median overall and prostate-specific antigen follow-up times were 6.8 years and 5.8 years, respectively. The overall 5-year rates for bRFS, DMFS, OS, and PCSM were 91.9%, 97.8%, 93.7%, and 0.71%, respectively. The 10-year rates were 81.5%, 91.5%, 76.1%, and 2.5%, respectively. The overall rates of late grade ≥3 GU and GI toxicity were 7.6% and 0.8%, respectively. On multivariable analysis, age and prostate length were significantly associated with increased risk of late grade ≥3 GU toxicity. The risk of incontinence was highly correlated with both pre-PI and post-PI transurethral resection of the prostate. Conclusions: Prostate brachytherapy as monotherapy is an effective treatment for low-risk and low-intermediate-risk prostate cancer and appears promising as a treatment for high-intermediate-risk and high-risk prostate cancer. Significant long-term toxicities are rare when brachytherapy is performed as monotherapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Adjuvant Radiation Therapy Treatment Time Impacts Overall Survival in Gastric Cancer

Purpose: Prolonged radiation therapy treatment time (RTT) is associated with worse survival in several tumor types. This study investigated whether delays during adjuvant radiation therapy impact overall survival (OS) in gastric cancer. Methods and Materials: The National Cancer Data Base was queried for patients with resected gastric cancer who received adjuvant radiation therapy with National Comprehensive Cancer Network–recommended doses (45 or 50.4 Gy) between 1998 and 2006. RTT was classified as standard (45 Gy: 33-36 days, 50.4 Gy: 38-41 days) or prolonged (45 Gy: >36 days, 50.4 Gy: >41 days). Cox proportional hazards models evaluated the association between the following factors and OS: RTT, interval from surgery to radiation therapy initiation, interval from surgery to radiation therapy completion, radiation therapy dose, demographic/pathologic and operative factors, and other elements of adjuvant multimodality therapy. Results: Of 1591 patients, RTT was delayed in 732 (46%). Factors associated with prolonged RTT were non-private health insurance (OR 1.3, P=.005) and treatment at non-academic facilities (OR 1.2, P=.045). Median OS and 5-year actuarial survival were significantly worse in patients with prolonged RTT compared with standard RTT (36 vs 51 months, P=.001; 39 vs 47%, P=.005); OS worsened with each cumulative week of delay (P<.0004). On multivariable analysis, prolonged RTT was associated with inferior OS (hazard ratio 1.2, P=.002); the intervals from surgery to radiation therapy initiation or completion were not. Prolonged RTT was particularly detrimental in patients with node positivity, inadequate nodal staging (<15 nodes examined), and those undergoing a cycle of chemotherapy before chemoradiation therapy. Conclusions: Delays during adjuvant radiation therapy appear to negatively impact survival in gastric cancer. Efforts to minimize cumulative interruptions to <7 days should be considered.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Reirradiation of Recurrent and Second Primary Head and Neck Cancer With Proton Therapy

Purpose: To report the clinical outcomes of head and neck reirradiation with proton therapy. Methods and Materials: From 2004 to 2014, 61 patients received curative-intent proton reirradiation, primarily for disease involving skull base structures, at a median of 23 months from the most recent previous course of radiation. Most had squamous cell (52.5%) or adenoid cystic (16.4%) carcinoma. Salvage surgery before reirradiation was undertaken in 47.5%. Gross residual disease was present in 70.5%. For patients with microscopic residual disease, the median dose of reirradiation was 66 Gy (relative biological effectiveness), and for gross disease was 70.2 Gy (relative biological effectiveness). Concurrent chemotherapy was given in 27.9%. Results: The median follow-up time was 15.2 months and was 28.7 months for patients remaining alive. The 2-year overall survival estimate was 32.7%, and the median overall survival was 16.5 months. The 2-year cumulative incidence of local failure with death as a competing risk was 19.7%; regional nodal failure, 3.3%; and distant metastases, 38.3%. On multivariable analysis, Karnofsky performance status ≤70%, the presence of a gastrostomy tube before reirradiation, and an increasing number of previous courses of radiation therapy were associated with a greater hazard ratio for death. A cutaneous primary tumor, gross residual disease, increasing gross tumor volume, and a lower radiation dose were associated with a greater hazard ratio for local failure. Grade ≥3 toxicities were seen in 14.7% acutely and 24.6% in the late setting, including 3 treatment-related deaths. Conclusions: Reirradiation with proton therapy, with or without chemotherapy, provided reasonable locoregional disease control, toxicity profiles, and survival outcomes for an advanced-stage and heavily pretreated population. Additional data are needed to identify which patients are most likely to benefit from aggressive efforts to achieve local disease control and to evaluate the potential benefit of proton therapy relative to other modalities of reirradiation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Contemporary Trends in Radiation Oncology Resident Research

Purpose: To test the hypothesis that recent resident research productivity might be different than a decade ago, and to provide contemporary information about resident scholarly activity. Methods and Materials: We compiled a list of radiation oncology residents from the 2 most recent graduating classes (June 2014 and 2015) using the Association of Residents in Radiation Oncology annual directories. We queried the PubMed database for each resident's first-authored publications from postgraduate years (PGY) 2 through 5, plus a 3-month period after residency completion. We abstracted corresponding historical data for 2002 to 2007 from the benchmark publication by Morgan and colleagues (Int J Radiat Oncol Biol Phys 2009;74:1567-1572). We tested the null hypothesis that these 2 samples had the same distribution for number of publications using the Wilcoxon rank-sum test. We explored the association of demographic factors and publication number using multivariable zero-inflated Poisson regression. Results: There were 334 residents publishing 659 eligible first-author publications during residency (range 0-17; interquartile range 0-3; mean 2.0; median 1). The contemporary and historical distributions were significantly different (P<.001); contemporary publication rates were higher. Publications accrued late in residency (27% in PGY-4, 59% in PGY-5), and most were original research (75%). In the historical cohort, half of all articles were published in 3 journals; in contrast, the top half of contemporary publications were spread over 10 journals—most commonly International Journal of Radiation Oncology • Biology • Physics (17%), Practical Radiation Oncology (7%), and Radiation Oncology (4%). Male gender, non-PhD status, and larger residency size were associated with higher number of publications in the multivariable analysis. Conclusion: We observed an increase in first-author publications during training compared with historical data from the mid-2000s. These contemporary figures may be useful to medical students considering radiation oncology, current residents, training programs, and prospective employers.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

Quality of Life in Long-term Survivors of Muscle-Invasive Bladder Cancer

Purpose: Health-related quality of life (QOL) has not been well-studied in survivors of muscle-invasive bladder cancer (MIBC). The present study compared long-term QOL in MIBC patients treated with radical cystectomy (RC) versus bladder-sparing trimodality therapy (TMT). Methods and Materials: This cross-sectional bi-institutional study identified 226 patients with nonmetastatic cT2-cT4 MIBC, diagnosed in 1990 to 2011, who were eligible for RC and were disease free for ≥2 years. Six validated QOL instruments were administered: EuroQOL EQ-5D, European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Core Questionnaire and EORTC MIBC module, Expanded Prostate Cancer Index Composite bowel scale, Cancer Treatment and Perception Scale, and Impact of Cancer, version 2. Multivariable analyses of the mean QOL scores were conducted using propensity score matching. Results: The response rate was 77% (n=173). The median follow-up period was 5.6 years. Of the 173 patients, 64 received TMT and 109, RC. The median interval from diagnosis to questionnaire completion was 9 years after TMT and 7 years after RC (P=.009). No significant differences were found in age, gender, comorbidities, tobacco history, performance status, or tumor stage. On multivariable analysis, patients who received TMT had better general QOL by 9.7 points of 100 compared with those who had received RC (P=.001) and higher physical, role, social, emotional, and cognitive functioning by 6.6 to 9.9 points (P≤.04). TMT was associated with better bowel function by 4.5 points (P=.02) and fewer bowel symptoms by 2.7 to 7.1 points (P≤.05). The urinary symptom scores were similar. TMT was associated with better sexual function by 8.7 to 32.1 points (P≤.02) and body image by 14.8 points (P<.001). The patients who underwent TMT reported greater informed decision-making scores by 13.6 points (P=.01) and less concern about the negative effect of cancer by 6.8 points (P=.006). The study limitations included missing baseline QOL data and different follow-up times. Conclusions: Both TMT and RC result in good long-term QOL outcomes in MIBC survivors, supporting TMT as a good alternative to RC for selected patients. Whether TMT leads to superior QOL requires prospective validation.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Volume of Lytic Vertebral Body Metastatic Disease Quantified Using Computed Tomography–Based Image Segmentation Predicts Fracture Risk After Spine Stereotactic Body Radiation Therapy

Purpose: To determine a threshold of vertebral body (VB) osteolytic or osteoblastic tumor involvement that would predict vertebral compression fracture (VCF) risk after stereotactic body radiation therapy (SBRT), using volumetric image-segmentation software. Methods and Materials: A computational semiautomated skeletal metastasis segmentation process refined in our laboratory was applied to the pretreatment planning CT scan of 100 vertebral segments in 55 patients treated with spine SBRT. Each VB was segmented and the percentage of lytic and/or blastic disease by volume determined. Results: The cumulative incidence of VCF at 3 and 12 months was 14.1% and 17.3%, respectively. The median follow-up was 7.3 months (range, 0.6-67.6 months). In all, 56% of segments were determined lytic, 23% blastic, and 21% mixed, according to clinical radiologic determination. Within these 3 clinical cohorts, the segmentation-determined mean percentages of lytic and blastic tumor were 8.9% and 6.0%, 0.2% and 26.9%, and 3.4% and 15.8% by volume, respectively. On the basis of the entire cohort (n=100), a significant association was observed for the osteolytic percentage measures and the occurrence of VCF (P<.001) but not for the osteoblastic measures. The most significant lytic disease threshold was observed at ≥11.6% (odds ratio 37.4, 95% confidence interval 9.4-148.9). On multivariable analysis, ≥11.6% lytic disease (P<.001), baseline VCF (P<.001), and SBRT with ≥20 Gy per fraction (P=.014) were predictive. Conclusions: Pretreatment lytic VB disease volumetric measures, independent of the blastic component, predict for SBRT-induced VCF. Larger-scale trials evaluating our software are planned to validate the results.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Longitudinal Changes in Active Bone Marrow for Cervical Cancer Patients Treated With Concurrent Chemoradiation Therapy

Purpose: To quantify longitudinal changes in active bone marrow (ABM) distributions within unirradiated (extrapelvic) and irradiated (pelvic) bone marrow (BM) in cervical cancer patients treated with concurrent chemoradiation therapy (CRT). Methods and Materials: We sampled 39 cervical cancer patients treated with CRT, of whom 25 were treated with concurrent cisplatin (40 mg/m{sup 2}) and 14 were treated with cisplatin (40 mg/m{sup 2}) plus gemcitabine (50-125 mg/m{sup 2}) (C/G). Patients underwent {sup 18}F-fluorodeoxyglucose positron emission tomographic/computed tomographic imaging at baseline and 1.5 to 6.0 months after treatment. ABM was defined as the subvolume of bone with standardized uptake value (SUV) above the mean SUV of the total bone. The primary aim was to measure the compensatory response, defined as the change in the log of the ratio of extrapelvic versus pelvic ABM percentage from baseline to after treatment. We also quantified the change in the proportion of ABM and mean SUV in pelvic and extrapelvic BM using a 2-sided paired t test. Results: We observed a significant increase in the overall extrapelvic compensatory response after CRT (0.381; 95% confidence interval [CI]: 0.312, 0.449) and separately in patients treated with cisplatin (0.429; 95% CI: 0.340, 0.517) and C/G (0.294; 95% CI: 0.186, 0.402). We observed a trend toward higher compensatory response in patients treated with cisplatin compared with C/G (P=.057). Pelvic ABM percentage was reduced after CRT both in patients receiving cisplatin (P<.001) and in those receiving C/G (P<.001), whereas extrapelvic ABM percentage was increased in patients receiving cisplatin (P<.001) and C/G (P<.001). The mean SUV in pelvic structures was lower after CRT with both cisplatin (P<.001) and C/G (P<.001). The mean SUV appeared lower in extrapelvic structures after CRT in patients treated with C/G (P=.076) but not with cisplatin (P=.942). We also observed that older age and more intense chemotherapy regimens were correlated with a decreased compensatory response on multivariable analysis. In patients treated with C/G, mean pelvic bone marrow dose was found to be negatively correlated with the compensatory response. Conclusion: Patients have differing subacute compensatory responses after CRT, owing to variable recovery in unirradiated marrow. Intensive chemotherapy regimens appear to decrease the extrapelvic compensatory response, which may lead to increased hematologic toxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Effect of Intensity Modulated Radiation Therapy With Concurrent Chemotherapy on Survival for Patients With Cervical Esophageal Carcinoma

Purpose: We evaluated the effect of consecutive protocols on overall survival (OS) for cervical esophageal carcinoma (CEC). Methods and Materials: All CEC cases that received definitive radiation therapy (RT) with or without chemotherapy from 1997 to 2013 in 3 consecutive protocols were reviewed. Protocol 1 (P1) consisted of 2-dimensional RT of 54 Gy in 20 fractions with 5-fluorouracil plus either mitomycin C or cisplatin. Protocol 2 (P2) consisted of 3-dimensional conformal RT (3DRT) of ≥60 Gy in 30 fractions plus elective nodal irradiation plus cisplatin. Protocol 3 (P3) consisted of intensity modulated RT (IMRT) of ≥60 Gy in 30 fractions plus elective nodal irradiation plus cisplatin. Multivariable analyses were used to assess the effect of the treatment protocol, RT technique, and RT dose on OS, separately. Results: Of 81 cases (P1, 21; P2, 23; and P3, 37), 34 local (P1, 11 [52%]; P2, 12 [52%]; and P3, 11 [30%]), 16 regional (P1, 6 [29%]); P2, 3 [13%]; and P3, 7 [19%]), and 34 distant (P1, 10 [48%]; P2, 9 [39%]; and P3, 15 [41%]) failures were identified. After adjusting for age (P=.49) and chemotherapy (any vs none; hazard ratio [HR] 0.5, 95% confidence interval [CI] 0.3-0.9; P=.023), multivariable analysis showed P3 had improved OS compared with P1 (HR 0.4, 95% CI 0.2-0.8; P=.005), with a trend shown for benefit compared with P2 (HR 0.6, 95% CI 0.3-1.0; P=.061). OS between P1 and P2 did not differ (P=.29). Analyzed as a continuous variable, higher RT doses were associated with a borderline improved OS (HR 0.97, 95% CI 0.95-1.0; P=.075). IMRT showed improved OS compared with non-IMRT (HR 0.57, 95% CI 0.3-0.8; P=.008). Conclusions: The present retrospective consecutive cohort study showed improved OS with our current protocol (P3; high-dose IMRT with concurrent high-dose cisplatin) compared with historical protocols. The outcomes for patients with CEC remain poor, and novel approaches to improve the therapeutic ratio are warranted.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Dry Eye Syndrome After Proton Therapy of Ocular Melanomas

Purpose: To investigate whether proton therapy (PT) performs safely in superotemporal melanomas, in terms of risk of dry-eye syndrome (DES). Methods and Materials: Tumor location, DES grade, and dose to ocular structures were analyzed in patients undergoing PT (2005-2015) with 52 Gy (prescribed dose, not accounting for biologic effectiveness correction of 1.1). Prognostic factors of DES and severe DES (sDES, grades 2-3) were determined with Cox proportional hazard models. Visual acuity deterioration and enucleation rates were compared by sDES and tumor locations. Results: Median follow-up was 44 months (interquartile range, 18-60 months). Of 853 patients (mean age, 64 years), 30.5% had temporal and 11.4% superotemporal tumors. Five-year incidence of DES and sDES was 23.0% (95% confidence interval [CI] 19.0%-27.7%) and 10.9% (95% CI 8.2%-14.4%), respectively. Multivariable analysis showed a higher risk for sDES in superotemporal (hazard ratio [HR] 5.82, 95% CI 2.72-12.45) and temporal tumors (HR 2.63, 95% CI 1.28-5.42), age ≥70 years (HR 1.90, 95% CI 1.09-3.32), distance to optic disk ≥5 mm (HR 2.71, 95% CI 1.52-4.84), ≥35% of retina receiving 12 Gy (HR 2.98, 95% CI 1.54-5.77), and eyelid rim irradiation (HR 2.68, 95% CI 1.49-4.80). The same risk factors were found for DES. Visual acuity deteriorated more in patients with sDES (0.86 ± 1.10 vs 0.64 ± 0.98 logMAR, P=.034) but not between superotemporal/temporal and other locations (P=.890). Enucleation rates were independent of sDES (P=.707) and tumor locations (P=.729). Conclusions: Severe DES was more frequent in superotemporal/temporal melanomas. Incidence of vision deterioration and enucleation was no higher in patients with superotemporal melanoma than in patients with tumors in other locations. Tumor location should not contraindicate PT.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Burnout Evaluation of Radiation Residents Nationwide: Results of a Survey of United States Residents

Purpose: To assess rates of burnout among US radiation oncology residents and evaluate program/resident factors associated with burnout. Methods and Materials: A nationwide survey was distributed to residents in all US radiation oncology programs. The survey included the Maslach Burnout Index–Human Services Survey (MBI-HSS) as well as demographic and program-specific questions tailored to radiation oncology residents. Primary endpoints included rates of emotional exhaustion, depersonalization, and personal accomplishment from MBI-HSS subscale scores. Binomial logistic models determined associations between various residency/resident characteristics and high burnout levels. Results: Overall, 232 of 733 residents (31.2%) responded, with 205 of 733 (27.9%) completing the MBI-HSS. High levels of emotional exhaustion and depersonalization were reported in 28.3% and 17.1%, respectively; 33.1% experienced a high burnout level on at least 1 of these 2 MBI-HSS subscales. Low rates of personal accomplishment occurred in 12% of residents. Twelve residents (5.9%) reported feeling “at the end of my rope” on a weekly basis or more. On multivariable analysis there was a statistically significant inverse association between perceived adequacy of work-life balance (odds ratio 0.37; 95% confidence interval 0.17-0.83) and burnout. Conclusions: Approximately one-third of radiation oncology residents have high levels of burnout symptoms, consistent with previous oncology literature, but lower levels than those among physicians and residents of other specialties. Particularly concerning was that more than 1 in 20 felt “at the end of my rope” on a weekly basis or more. Targeted interventions to identify symptoms of burnout among radiation oncology residents may help to prevent the negative downstream consequences of this syndrome.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Search for WH associated production in 5.3 fb -1 of p p ¯ collisions at the Fermilab Tevatron

We present a search for associated production of Higgs and W bosons in collisions at a center of mass energy of in 5.3 fb -1 of integrated luminosity recorded by the D0 experiment. Multivariate analysis techniques are applied to events containing one lepton, an imbalance in transverse energy, and one or two b-tagged jets to discriminate a potential WH signal from Standard Model backgrounds. We observe good agreement between data and expected backgrounds, and set an upper limit of 4.5 (at 95% confidence level and for m H =115 GeV) on the ratio of the WH cross section multiplied by the branching fraction of H → bb¯ to its Standard Model prediction, which is consistent with an expected limit of 4.8.

Abazov, V.M.↗
DOE OSTI2023

Observation of four top quark production in proton-proton collisions at s = 13 TeV

The observation of the production of four top quarks in proton-proton collisions is reported, based on a data sample collected by the CMS experiment at a center-of-mass energy of 13 TeV in 2016–2018 at the CERN LHC and corresponding to an integrated luminosity of 138 fb − 1 . Events with two same-sign, three, or four charged leptons (electrons and muons) and additional jets are analyzed. Compared to previous results in these channels, updated identification techniques for charged leptons and jets originating from the hadronization of b quarks, as well as a revised multivariate analysis strategy to distinguish the signal process from the main backgrounds, lead to an improved expected signal significance of 4.9 standard deviations above the background-only hypothesis. Four top quark production is observed with a significance of 5.6 standard deviations, and its cross section is measured to be 17.7 − 3.5 + 3.7 (stat) − 1.9 + 2.3 (syst) fb , in agreement with the available standard model predictions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗