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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 649 records · Page 36
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Acute Esophagus Toxicity in Lung Cancer Patients After Intensity Modulated Radiation Therapy and Concurrent Chemotherapy

Purpose: The purpose of this study was to investigate the dose-effect relation between acute esophageal toxicity (AET) and the dose-volume parameters of the esophagus after intensity modulated radiation therapy (IMRT) and concurrent chemotherapy for patients with non-small cell lung cancer (NSCLC). Patients and Methods: One hundred thirty-nine patients with inoperable NSCLC treated with IMRT and concurrent chemotherapy were prospectively analyzed. The fractionation scheme was 66 Gy in 24 fractions. All patients received concurrently a daily dose of cisplatin (6 mg/m Superscript-Two ). Maximum AET was scored according to Common Toxicity Criteria 3.0. Dose-volume parameters V5 to V70, D{sub mean} and D{sub max} of the esophagus were calculated. A logistic regression analysis was performed to analyze the dose-effect relation between these parameters and grade {>=}2 and grade {>=}3 AET. The outcome was compared with the clinically used esophagus V35 prediction model for grade {>=}2 after radical 3-dimensional conformal radiation therapy (3DCRT) treatment. Results: In our patient group, 9% did not experience AET, and 31% experienced grade 1 AET, 38% grade 2 AET, and 22% grade 3 AET. The incidence of grade 2 and grade 3 AET was not different from that in patients treated with CCRT using 3DCRT. The V50 turned out to be the most significant dosimetric predictor for grade {>=}3 AET (P=.012). The derived V50 model was shown to predict grade {>=}2 AET significantly better than the clinical V35 model (P<.001). Conclusions: For NSCLC patients treated with IMRT and concurrent chemotherapy, the V50 was identified as most accurate predictor of grade {>=}3 AET. There was no difference in the incidence of grade {>=}2 AET between 3DCRT and IMRT in patients treated with concurrent chemoradiation therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Impact of Neoadjuvant Prostate-Specific Antigen Kinetics on Biochemical Failure and Prostate Cancer Mortality: Results From a Prospective Patient Database

Purpose: To confirm findings from an earlier report showing that neoadjuvant (NA) prostate-specific antigen (PSA) halving time (PSAHT) impacts biochemical failure (BF) rates, and to examine its association with prostate cancer-specific survival (PCSS), in a large prospective cohort of patients. Methods and Materials: A total of 502 patients were selected from a prospective database, who had localized prostate adenocarcinoma treated with 2-12 months of neoadjuvant androgen deprivation therapy (N-ADT) followed by external beam radiation therapy (EBRT) between 1994 and 2000, and had at least 2 NA PSA values. Seventy-four percent of patients had high-risk prostate cancer. Median initial PSA value, N-ADT duration, total ADT duration, and radiation therapy dose were 14 ng/mL, 6.9 months, 10.8 months, and 68 Gy, respectively. Results: At a median follow-up of 9.9 years, 210 patients have had a BF. Median PSAHT was 18 days. On univariate analysis, PSAHT was not shown to predict for BF (P=.69) or PCSS (P=.28). However, NA nadir PSA (nanPSA) and post-therapy nadir PSA (ptnPSA), when analyzed as continuous or categoric variables, predicted for BF (P<.001) and PCSS (P<.001). On multivariate analysis, nanPSA (P=.037) and ptnPSA (P<.001) continued to be significantly associated with BF. However, N-ADT duration lost significance (P=.67), and PSAHT remained a nonsignificant predictor (P=.97). For PCSS, multivariate analysis showed nanPSA (P=.049) and ptnPSA (P<.001) to be significant. Again PSAHT (P=.49) remained nonsignificant. Conclusions: In this large, prospective cohort of patients, NA PSA kinetics, expressed as PSAHT, did not predict BF or PCSS. However, nadir PSAs, in both the NA and post-therapy settings, were significant predictors of BF and PCSS. Optimization of therapy could potentially be based on early PSA response, with shorter durations of ADT for those predicted to do favorably, and intensification of therapy for those likely to have poorer outcomes.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Delayed Complications in Patients Surviving at Least 3 Years After Stereotactic Radiosurgery for Brain Metastases

Purpose: Little is known about delayed complications after stereotactic radiosurgery in long-surviving patients with brain metastases. We studied the actual incidence and predictors of delayed complications. Patients and Methods: This was an institutional review board-approved, retrospective cohort study that used our database. Among our consecutive series of 2000 patients with brain metastases who underwent Gamma Knife radiosurgery (GKRS) from 1991-2008, 167 patients (8.4%, 89 women, 78 men, mean age 62 years [range, 19-88 years]) who survived at least 3 years after GKRS were studied. Results: Among the 167 patients, 17 (10.2%, 18 lesions) experienced delayed complications (mass lesions with or without cyst in 8, cyst alone in 8, edema in 2) occurring 24.0-121.0 months (median, 57.5 months) after GKRS. The actuarial incidences of delayed complications estimated by competing risk analysis were 4.2% and 21.2% at the 60th month and 120th month, respectively, after GKRS. Among various pre-GKRS clinical factors, univariate analysis demonstrated tumor volume-related factors: largest tumor volume (hazard ratio [HR], 1.091; 95% confidence interval [CI], 1.018-1.154; P=.0174) and tumor volume {<=}10 cc vs >10 cc (HR, 4.343; 95% CI, 1.444-12.14; P=.0108) to be the only significant predictors of delayed complications. Univariate analysis revealed no correlations between delayed complications and radiosurgical parameters (ie, radiosurgical doses, conformity and gradient indexes, and brain volumes receiving >5 Gy and >12 Gy). After GKRS, an area of prolonged enhancement at the irradiated lesion was shown to be a possible risk factor for the development of delayed complications (HR, 8.751; 95% CI, 1.785-157.9; P=.0037). Neurosurgical interventions were performed in 13 patients (14 lesions) and mass removal for 6 lesions and Ommaya reservoir placement for the other 8. The results were favorable. Conclusions: Long-term follow-up is crucial for patients with brain metastases treated with GKRS because the risk of complications long after treatment is not insignificant. However, even when delayed complications occur, favorable outcomes can be expected with timely neurosurgical intervention.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

The Impact of Local and Regional Disease Extent on Overall Survival in Patients With Advanced Stage IIIB/IV Non-Small Cell Lung Carcinoma

Purpose: Patients with advanced stage IIIB or stage IV non-small cell lung carcinoma are typically treated with initial platinum-based chemotherapy. A variety of factors (eg, performance status, gender, age, histology, weight loss, and smoking history) are generally accepted as predictors of overall survival. Because uncontrolled pulmonary disease constitutes a major cause of death in these patients, we hypothesized that clinical and radiographic factors related to intrathoracic disease at diagnosis may be prognostically significant in addition to conventional factors. The results have implications regarding the selection of patients for whom palliative thoracic radiation therapy may be of most benefit. Methods and Materials: We conducted a pooled analysis of 189 patients enrolled at a single institution into 9 prospective phase II and III clinical trials involving first-line, platinum-based chemotherapy. Baseline clinical and radiographic characteristics before trial enrollment were analyzed as possible predictors for subsequent overall survival. To assess the relationship between anatomic location and volume of disease within the thorax and its effect on survival, the pre-enrollment computed tomography images were also analyzed by contouring central and peripheral intrapulmonary disease. Results: On univariate survival analysis, multiple pulmonary-related factors were significantly associated with worse overall survival, including pulmonary symptoms at presentation (P=.0046), total volume of intrathoracic disease (P=.0006), and evidence of obstruction of major bronchi or vessels on prechemotherapy computed tomography (P<.0001). When partitioned into central and peripheral volumes, central (P<.0001) but not peripheral (P=.74) disease was associated with worse survival. On multivariate analysis with known factors, pulmonary symptoms (hazard ratio, 1.46; P=.042), central disease volume (hazard ratio, 1.47; P=.042), and bronchial/vascular compression (hazard ratio, 1.54; P=.022) remained significant. Conclusions: Patients with bulky central disease, bronchial/vascular compression, and/or pulmonary symptoms exhibited worse overall survival after first-line, platinum-based chemotherapy. A subset of these patients may be studied to determine whether early, planned palliative thoracic radiation could also be of benefit.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Gamma Knife Radiosurgery for the Treatment of Cystic Cerebral Metastases

Purpose: To assess the role of Gamma Knife radiosurgery (GKRS) in the treatment of nonsurgical cystic brain metastasis, and to determine predictors of response to GKRS. Methods: We reviewed a prospectively maintained database of brain metastases patients treated at our institution between 2006 and 2010. All lesions with a cystic component were identified, and volumetric analysis was done to measure percentage of cystic volume on day of treatment and consecutive follow-up MRI scans. Clinical, radiologic, and dosimetry parameters were reviewed to establish the overall response of cystic metastases to GKRS as well as identify potential predictive factors of response. Results: A total of 111 lesions in 73 patients were analyzed; 57% of lesions received prior whole-brain radiation therapy (WBRT). Lung carcinoma was the primary cancer in 51% of patients, 10% breast, 10% colorectal, 4% melanoma, and 26% other. Fifty-seven percent of the patients were recursive partitioning analysis class 1, the remainder class 2. Mean target volume was 3.3 mL (range, 0.1-23 mL). Median prescription dose was 21 Gy (range, 15-24 Gy). Local control rates were 91%, 63%, and 37% at 6, 12, and 18 months, respectively. Local control was improved in lung primary and worse in patients with prior WBRT (univariate). Only lung primary predicted local control in multivariate analysis, whereas age and tumor volume did not. Lesions with a large cystic component did not show a poorer response compared with those with a small cystic component. Conclusions: This study supports the use of GKRS in the management of nonsurgical cystic metastases, despite a traditionally perceived poorer response. Our local control rates are comparable to a matched cohort of noncystic brain metastases, and therefore the presence of a large cystic component should not deter the use of GKRS. Predictors of response included tumor subtype. Prior WBRT decreased effectiveness of SRS for local control rates.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Short-term Androgen-Deprivation Therapy Improves Prostate Cancer-Specific Mortality in Intermediate-Risk Prostate Cancer Patients Undergoing Dose-Escalated External Beam Radiation Therapy

Purpose: We investigated the benefit of short-term androgen-deprivation therapy (ADT) in patients with intermediate-risk prostate cancer (PC) receiving dose-escalated external beam radiation therapy. Methods and Materials: The present retrospective study comprised 710 intermediate-risk PC patients receiving external beam radiation therapy with doses of ≥81 Gy at a single institution from 1992 to 2005, including 357 patients receiving neoadjuvant and concurrent ADT. Prostate-specific antigen recurrence-free survival (PSA-RFS) and distant metastasis (DM) were compared using the Kaplan-Meier method and Cox proportional hazards models. PC-specific mortality (PCSM) was assessed using competing-risks analysis. Results: The median follow-up was 7.9 years. Despite being more likely to have higher PSA levels, Gleason score 4 + 3 = 7, multiple National Comprehensive Cancer Network intermediate-risk factors, and older age (P≤.001 for all comparisons), patients receiving ADT had improved PSA-RFS (hazard ratio [HR], 0.598; 95% confidence interval [CI], 0.435-0.841; P=.003), DM (HR, 0.424; 95% CI, 0.219-0.819; P=.011), and PCSM (HR, 0.380; 95% CI, 0.157-0.921; P=.032) on univariate analysis. Using multivariate analysis, ADT was an even stronger predictor of improved PSA-RFS (adjusted HR [AHR], 0.516; 95% CI, 0.360-0.739; P<.001), DM (AHR, 0.347; 95% CI, 0.176-0.685; P=.002), and PCSM (AHR, 0.297; 95% CI, 0.128-0.685; P=.004). Gleason score 4 + 3 = 7 and ≥50% positive biopsy cores were other independent predictors of PCSM. Conclusions: Short-term ADT improves PSA-RFS, DM, and PCSM in patients with intermediate-risk PC undergoing dose-escalated external beam radiation therapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Cosmetic Analysis Following Breast-Conserving Surgery and Adjuvant High-Dose-Rate Interstitial Brachytherapy for Early-Stage Breast Cancer: A Prospective Clinical Study

Purpose: To prospectively evaluate cosmetic outcomes in women treated with accelerated partial breast irradiation using high-dose-rate interstitial brachytherapy for early-stage breast cancer. Methods and Materials: Between 2004 and 2008, 151 patients with early-stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients had stage Tis-T2 tumors of ≤3 cm that were excised with negative margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. Both the patients and the treating radiation oncologist qualitatively rated cosmesis as excellent, good, fair, or poor over time and ascribed a cause for changes in cosmesis. Cosmetic outcome was evaluated quantitatively by percentage of breast retraction assessment (pBRA). Patients also reported their satisfaction with treatment over time. Results: Median follow-up was 55 months. The rates of excellent-to-good cosmesis reported by patients and the treating radiation oncologist were 92% and 97% pretreatment, 91% and 97% at 3 to 4 months' follow-up, 87% and 94% at 2 years, and 92% and 94% at 3 years, respectively. Breast infection and adjuvant chemotherapy were independent predictors of a fair-to-poor cosmetic outcome at 3 years. Compared to pretreatment pBRA (7.35), there was no significant change in pBRA over time. The volume receiving more than 150 Gy (V150) was the only significant predictor of pBRA. The majority of patients (86.6%) were completely satisfied with their treatment. Conclusions: Patients and the treating physician reported a high rate of excellent-to-good cosmetic outcomes at all follow-up time points. Acute breast infection and chemotherapy were associated with worse cosmetic outcomes. Multicatheter interstitial brachytherapy does not significantly change breast size as measured by pBRA.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Preoperative 3-Tesla Multiparametric Endorectal Magnetic Resonance Imaging Findings and the Odds of Upgrading and Upstaging at Radical Prostatectomy in Men With Clinically Localized Prostate Cancer

Purpose: To investigate whether 3-T esla (3T) multiparametric endorectal MRI (erMRI) can add information to established predictors regarding occult extraprostatic or high-grade prostate cancer (PC) in men with clinically localized PC. Methods and Materials: At a single academic medical center, this retrospective study's cohort included 118 men with clinically localized PC who underwent 3T multiparametric erMRI followed by radical prostatectomy, from 2008 to 2011. Multivariable logistic regression analyses in all men and in 100 with favorable-risk PC addressed whether erMRI evidence of T3 disease was associated with prostatectomy T3 or Gleason score (GS) 8-10 (in patients with biopsy GS {<=}7) PC, adjusting for age, prostate-specific antigen level, clinical T category, biopsy GS, and percent positive biopsies. Results: The accuracy of erMRI prediction of extracapsular extension and seminal vesicle invasion was 75% and 95%, respectively. For all men, erMRI evidence of a T3 lesion versus T2 was associated with an increased odds of having pT3 disease (adjusted odds ratio [AOR] 4.81, 95% confidence interval [CI] 1.36-16.98, P=.015) and pGS 8-10 (AOR 5.56, 95% CI 1.10-28.18, P=.038). In the favorable-risk population, these results were AOR 4.14 (95% CI 1.03-16.56), P=.045 and AOR 7.71 (95% CI 1.36-43.62), P=.021, respectively. Conclusions: Three-Tesla multiparametric erMRI in men with favorable-risk PC provides information beyond that contained in known preoperative predictors about the presence of occult extraprostatic and/or high-grade PC. If validated in additional studies, this information can be used to counsel men planning to undergo radical prostatectomy or radiation therapy about the possible need for adjuvant radiation therapy or the utility of adding hormone therapy, respectively.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Spatial-Temporal [{sup 18}F]FDG-PET Features for Predicting Pathologic Response of Esophageal Cancer to Neoadjuvant Chemoradiation Therapy

Purpose: To extract and study comprehensive spatial-temporal {sup 18}F-labeled fluorodeoxyglucose ([{sup 18}F]FDG) positron emission tomography (PET) features for the prediction of pathologic tumor response to neoadjuvant chemoradiation therapy (CRT) in esophageal cancer. Methods and Materials: Twenty patients with esophageal cancer were treated with trimodal therapy (CRT plus surgery) and underwent [{sup 18}F]FDG-PET/CT scans both before (pre-CRT) and after (post-CRT) CRT. The 2 scans were rigidly registered. A tumor volume was semiautomatically delineated using a threshold standardized uptake value (SUV) of ≥2.5, followed by manual editing. Comprehensive features were extracted to characterize SUV intensity distribution, spatial patterns (texture), tumor geometry, and associated changes resulting from CRT. The usefulness of each feature in predicting pathologic tumor response to CRT was evaluated using the area under the receiver operating characteristic curve (AUC) value. Results: The best traditional response measure was decline in maximum SUV (SUV{sub max}; AUC, 0.76). Two new intensity features, decline in mean SUV (SUV{sub mean}) and skewness, and 3 texture features (inertia, correlation, and cluster prominence) were found to be significant predictors with AUC values ≥0.76. According to these features, a tumor was more likely to be a responder when the SUV{sub mean} decline was larger, when there were relatively fewer voxels with higher SUV values pre-CRT, or when [{sup 18}F]FDG uptake post-CRT was relatively homogeneous. All of the most accurate predictive features were extracted from the entire tumor rather than from the most active part of the tumor. For SUV intensity features and tumor size features, changes were more predictive than pre- or post-CRT assessment alone. Conclusion: Spatial-temporal [{sup 18}F]FDG-PET features were found to be useful predictors of pathologic tumor response to neoadjuvant CRT in esophageal cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Stereotactic Ablative Body Radiation Therapy for Octogenarians With Non-Small Cell Lung Cancer

Purpose: To retrospectively investigate treatment outcomes of stereotactic ablative body radiation therapy (SABR) for octogenarians with non-small cell lung cancer (NSCLC). Methods and Materials: Between 2005 and 2012, 109 patients aged ≥80 years with T1-2N0M0 NSCLC were treated with SABR: 47 patients had histology-unproven lung cancer; 62 patients had pathologically proven NSCLC. The prescribed doses were either 50 Gy/5 fractions for peripheral tumors or 40 Gy/5 fractions for centrally located tumors. The treatment outcomes, toxicities, and the correlating factors for overall survival (OS) were evaluated. Results: The median follow-up duration after SABR was 24.2 (range, 3.0-64.6) months. Only limited toxicities were observed, except for 1 grade 5 radiation pneumonitis. The 3-year local, regional, and distant metastasis-free survival rates were 82.3%, 90.1%, and 76.8%, respectively. The OS and lung cancer-specific survival rates were 53.7% and 70.8%, respectively. Multivariate analysis revealed that medically inoperable, low body mass index, high T stage, and high C-reactive protein were the predictors for short OS. The OS for the operable octogenarians was significantly better than that for inoperable (P<.01). Conclusions: Stereotactic ablative body radiation therapy for octogenarians was feasible, with excellent OS. Multivariate analysis revealed that operability was one of the predictors for OS. For medically operable octogenarians with early-stage NSCLC, SABR should be prospectively compared with resection.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Salvage HDR Brachytherapy for Recurrent Prostate Cancer After Previous Definitive Radiation Therapy: 5-Year Outcomes

Purpose: Evaluate efficacy and toxicity of salvage high-dose-rate brachytherapy (HDRB) for locally recurrent prostate cancer after definitive radiation therapy (RT). Methods and Materials: We retrospectively analyzed 52 consecutively accrued patients undergoing salvage HDRB between 1998 and 2009 for locally recurrent prostate cancer after previous definitive RT. After pathologic confirmation of locally recurrent disease, patients received 36 Gy in 6 fractions. Twenty-four patients received neoadjuvant hormonal therapy before salvage, and no patients received adjuvant hormonal therapy. Determination of biochemical failure after salvage HDRB was based on the Phoenix definition. Overall survival (OS) and bF distributions were calculated using the Kaplan-Meier method. Univariate analyses were performed to identify predictors of biochemical control. Acute and late genitourinary (GU) and gastrointestinal (GI) toxicities, based on Common Terminology Criteria for Adverse Events (version 4), were documented. Results: Median follow-up after salvage HDRB was 59.6 months. The 5-year OS estimate was 92% (95% confidence interval [CI]: 80%-97%) with median survival not yet reached. Five-year biochemical control after salvage was 51% (95% CI: 34%-66%). Median PSA nadir postsalvage was 0.1 (range: 0-7.2) reached at a median of 10.2 months after completing HDRB. As for complications, acute and late grade 3 GU toxicities were observed in only 2% and 2%, respectively. No grade 2 or higher acute GI events and 4% grade 2 GI late events were observed. On univariate analysis, disease-free interval after initial definitive RT (P=.07), percent of positive cores at the time of diagnosis (P=.08), interval from first recurrence to salvage HDRB (P=.09), and pre-HDRB prostate-specific antigen (P=.07) were each of borderline significance in predicting biochemical control after salvage HDRB. Conclusions: Prostate HDRB is an effective salvage modality with relatively few long-term toxicities. We provide potential predictors of biochemical control for prostate salvage HDRB.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Predicting Esophagitis After Chemoradiation Therapy for Non-Small Cell Lung Cancer: An Individual Patient Data Meta-Analysis

Purpose: Concurrent chemoradiation therapy (CCRT) improves survival compared with sequential treatment for locally advanced non-small cell lung cancer, but it increases toxicity, particularly radiation esophagitis (RE). Validated predictors of RE for clinical use are lacking. We performed an individual-patient-data meta-analysis to determine factors predictive of clinically significant RE. Methods and Materials: After a systematic review of the literature, data were obtained on 1082 patients who underwent CCRT, including patients from Europe, North America, Asia, and Australia. Patients were randomly divided into training and validation sets (2/3 vs 1/3 of patients). Factors predictive of RE (grade ≥2 and grade ≥3) were assessed using logistic modeling, with the concordance statistic (c statistic) used to evaluate the performance of each model. Results: The median radiation therapy dose delivered was 65 Gy, and the median follow-up time was 2.1 years. Most patients (91%) received platinum-containing CCRT regimens. The development of RE was common, scored as grade 2 in 348 patients (32.2%), grade 3 in 185 (17.1%), and grade 4 in 10 (0.9%). There were no RE-related deaths. On univariable analysis using the training set, several baseline factors were statistically predictive of RE (P<.05), but only dosimetric factors had good discrimination scores (c > .60). On multivariable analysis, the esophageal volume receiving ≥60 Gy (V60) alone emerged as the best predictor of grade ≥2 and grade ≥3 RE, with good calibration and discrimination. Recursive partitioning identified 3 risk groups: low (V60 <0.07%), intermediate (V60 0.07% to 16.99%), and high (V60 ≥17%). With use of the validation set, the predictive model performed inferiorly for the grade ≥2 endpoint (c = .58) but performed well for the grade ≥3 endpoint (c = .66). Conclusions: Clinically significant RE is common, but life-threatening complications occur in <1% of patients. Although several factors are statistically predictive of RE, the V60 alone provides the best predictive ability. Efforts to reduce the V60 should be prioritized, with further research needed to identify and validate new predictive factors.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

Conventional Versus Automated Implantation of Loose Seeds in Prostate Brachytherapy: Analysis of Dosimetric and Clinical Results

Purpose: To review the clinical outcome of I-125 permanent prostate brachytherapy (PPB) for low-risk and intermediate-risk prostate cancer and to compare 2 techniques of loose-seed implantation. Methods and Materials: 574 consecutive patients underwent I-125 PPB for low-risk and intermediate-risk prostate cancer between 2000 and 2008. Two successive techniques were used: conventional implantation from 2000 to 2004 and automated implantation (Nucletron, FIRST system) from 2004 to 2008. Dosimetric and biochemical recurrence-free (bNED) survival results were reported and compared for the 2 techniques. Univariate and multivariate analysis researched independent predictors for bNED survival. Results: 419 (73%) and 155 (27%) patients with low-risk and intermediate-risk disease, respectively, were treated (median follow-up time, 69.3 months). The 60-month bNED survival rates were 95.2% and 85.7%, respectively, for patients with low-risk and intermediate-risk disease (P=.04). In univariate analysis, patients treated with automated implantation had worse bNED survival rates than did those treated with conventional implantation (P<.0001). By day 30, patients treated with automated implantation showed lower values of dose delivered to 90% of prostate volume (D90) and volume of prostate receiving 100% of prescribed dose (V100). In multivariate analysis, implantation technique, Gleason score, and V100 on day 30 were independent predictors of recurrence-free status. Grade 3 urethritis and urinary incontinence were observed in 2.6% and 1.6% of the cohort, respectively, with no significant differences between the 2 techniques. No grade 3 proctitis was observed. Conclusion: Satisfactory 60-month bNED survival rates (93.1%) and acceptable toxicity (grade 3 urethritis <3%) were achieved by loose-seed implantation. Automated implantation was associated with worse dosimetric and bNED survival outcomes.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Interval Between Hysterectomy and Start of Radiation Treatment Is Predictive of Recurrence in Patients With Endometrial Carcinoma

Purpose: Adjuvant radiation therapy (RT) has been shown to improve local control in patients with endometrial carcinoma. We analyzed the impact of the time interval between hysterectomy and RT initiation in patients with endometrial carcinoma. Methods and Materials: In this institutional review board-approved study, we identified 308 patients with endometrial carcinoma who received adjuvant RT after hysterectomy. All patients had undergone hysterectomy, oophorectomy, and pelvic and para-aortic lymph node evaluation from 1988 to 2010. Patients' demographics, pathologic features, and treatments were compared. The time interval between hysterectomy and the start of RT was calculated. The effects of time interval on recurrence-free (RFS), disease-specific (DSS), and overall survival (OS) were calculated. Following univariate analysis, multivariate modeling was performed. Results: The median age and follow-up for the study cohort was 65 years and 72 months, respectively. Eighty-five percent of the patients had endometrioid carcinoma. RT was delivered with high-dose-rate brachytherapy alone (29%), pelvic RT alone (20%), or both (51%). Median time interval to start RT was 42 days (range, 21-130 days). A total of 269 patients (74%) started their RT <9 weeks after undergoing hysterectomy (group 1) and 26% started ≥9 weeks after surgery (group 2). There were a total of 43 recurrences. Tumor recurrence was significantly associated with treatment delay of ≥9 weeks, with 5-year RFS of 90% for group 1 compared to only 39% for group 2 (P<.001). On multivariate analysis, RT delay of ≥9 weeks (P<.001), presence of lymphovascular space involvement (P=.001), and higher International Federation of Gynecology and Obstetrics grade (P=.012) were independent predictors of recurrence. In addition, RT delay of ≥9 weeks was an independent significant predictor for worse DSS and OS (P=.001 and P=.01, respectively). Conclusions: Delay in administering adjuvant RT after hysterectomy was associated with worse survival endpoints. Our data suggest that shorter time interval between hysterectomy and start of RT may be beneficial.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2014

Neoadjuvant Chemoradiation Therapy Using Concurrent S-1 and Irinotecan in Rectal Cancer: Impact on Long-Term Clinical Outcomes and Prognostic Factors

Purpose: To assess the long-term outcomes of patients with rectal cancer who received neoadjuvant chemoradiation therapy (NCRT) with concurrent S-1 and irinotecan (S-1/irinotecan) therapy. Methods and Materials: The study group consisted of 115 patients with clinical stage T3 or T4 rectal cancer. Patients received pelvic radiation therapy (45 Gy) plus concurrent oral S-1/irinotecan. The median follow-up was 60 months. Results: Grade 3 adverse effects occurred in 7 patients (6%), and the completion rate of NCRT was 87%. All 115 patients (100%) were able to undergo R0 surgical resection. Twenty-eight patients (24%) had a pathological complete response (ypCR). At 60 months, the local recurrence-free survival was 93%, disease-free survival (DFS) was 79%, and overall survival (OS) was 80%. On multivariate analysis with a proportional hazards model, ypN2 was the only independent prognostic factor for DFS (P=.0019) and OS (P=.0064) in the study group as a whole. Multivariate analysis was additionally performed for the subgroup of 106 patients with ypN0/1 disease, who had a DFS rate of 85.3%. Both ypT (P=.0065) and tumor location (P=.003) were independent predictors of DFS. A combination of these factors was very strongly related to high risk of recurrence (P<.0001), which occurred most commonly in the lung. Conclusions: NCRT with concurrent S-1/irinotecan produced high response rates and excellent long-term survival, with acceptable adverse effects in patients with rectal cancer. ypN2 is a strong predictor of dismal outcomes, and a combination of ypT and tumor location can identify high-risk patients among those with ypN0/1 disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Rates and Durability of Response to Salvage Radiation Therapy Among Patients With Refractory or Relapsed Aggressive Non-Hodgkin Lymphoma

Purpose: To evaluate the response rate (RR) and time to local recurrence (TTLR) among patients who received salvage radiation therapy for relapsed or refractory aggressive non-Hodgkin lymphoma (NHL) and investigate whether RR and TTLR differed according to disease characteristics. Methods and Materials: A retrospective review was performed for all patients who completed a course of salvage radiation therapy between January 2001 and May 2011 at Brigham and Women's Hospital/Dana-Farber Cancer Institute. Separate analyses were conducted for patients treated with palliative and curative intent. Predictors of RR for each subgroup were assessed using a generalized estimating equation model. For patients treated with curative intent, local control (LC) and progression-free survival were estimated with the Kaplan-Meier method; predictors for TTLR were evaluated using a Cox proportional hazards regression model. Results: Salvage radiation therapy was used to treat 110 patients to 121 sites (76 curative, 45 palliative). Salvage radiation therapy was given as part of consolidation in 18% of patients treated with curative intent. Median dose was 37.8 Gy, with 58% and 36% of curative and palliative patients, respectively, receiving 39.6 Gy or higher. The RR was high (86% curative, 84% palliative). With a median follow-up of 4.8 years among living patients, 5-year LC and progression-free survival for curative patients were 66% and 34%, respectively. Refractory disease (hazard ratio 3.3; P=.024) and lack of response to initial chemotherapy (hazard ratio 4.3; P=.007) but not dose (P=.93) were associated with shorter TTLR. Despite doses of 39.6 Gy or higher, 2-year LC was only 61% for definitive patients with refractory disease or disease that did not respond to initial chemotherapy. Conclusions: Relapsed or refractory aggressive NHL is responsive to salvage radiation therapy, and durable LC can be achieved in some cases. However, refractory disease is associated with a shorter TTLR, suggesting that radiation dose escalation, addition of radiosensitizers, or a combination of both may be indicated in these patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Long-term Results of the UCSF-LBNL Randomized Trial: Charged Particle With Helium Ion Versus Iodine-125 Plaque Therapy for Choroidal and Ciliary Body Melanoma

Purpose: Relevant clinical data are needed given the increasing national interest in charged particle radiation therapy (CPT) programs. Here we report long-term outcomes from the only randomized, stratified trial comparing CPT with iodine-125 plaque therapy for choroidal and ciliary body melanoma. Methods and Materials: From 1985 to 1991, 184 patients met eligibility criteria and were randomized to receive particle (86 patients) or plaque therapy (98 patients). Patients were stratified by tumor diameter, thickness, distance to disc/fovea, anterior extension, and visual acuity. Tumors close to the optic disc were included. Local tumor control, as well as eye preservation, metastases due to melanoma, and survival were evaluated. Results: Median follow-up times for particle and plaque arm patients were 14.6 years and 12.3 years, respectively (P=.22), and for those alive at last follow-up, 18.5 and 16.5 years, respectively (P=.81). Local control (LC) for particle versus plaque treatment was 100% versus 84% at 5 years, and 98% versus 79% at 12 years, respectively (log rank: P=.0006). If patients with tumors close to the disc (<2 mm) were excluded, CPT still resulted in significantly improved LC: 100% versus 90% at 5 years and 98% versus 86% at 12 years, respectively (log rank: P=.048). Enucleation rate was lower after CPT: 11% versus 22% at 5 years and 17% versus 37% at 12 years, respectively (log rank: P=.01). Using Cox regression model, likelihood ratio test, treatment was the most important predictor of LC (P=.0002) and eye preservation (P=.01). CPT was a significant predictor of prolonged disease-free survival (log rank: P=.001). Conclusions: Particle therapy resulted in significantly improved local control, eye preservation, and disease-free survival as confirmed by long-term outcomes from the only randomized study available to date comparing radiation modalities in choroidal and ciliary body melanoma.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Adverse Outcomes After Palliative Radiation Therapy for Uncomplicated Spine Metastases: Role of Spinal Instability and Single-Fraction Radiation Therapy

Purpose: Level I evidence demonstrates equivalent pain response after single-fraction (SF) or multifraction (MF) radiation therapy (RT) for bone metastases. The purpose of this study is to provide additional data to inform the incidence and predictors of adverse outcomes after RT for spine metastases. Methods and Materials: At a single institution, 299 uncomplicated spine metastases (without cord compression, prior RT, or surgery) treated with RT from 2008 to 2013 were retrospectively reviewed. The spinal instability neoplastic score (SINS) was used to assess spinal instability. The primary outcome was time to first spinal adverse event (SAE) at the site, including symptomatic vertebral fracture, hospitalization for site-related pain, salvage surgery, interventional procedure, new neurologic symptoms, or cord compression. Fine and Gray's multivariable model assessed associations of the primary outcome with SINS, SF RT, and other significant baseline factors. Propensity score matched analysis further assessed the relationship of SF RT to first SAEs. Results: The cumulative incidence of first SAE after SF RT (n=66) was 6.8% at 30 days, 16.9% at 90 days, and 23.6% at 180 days. For MF RT (n=233), the incidence was 3.5%, 6.4%, and 9.2%, respectively. In multivariable analysis, SF RT (hazard ratio [HR] = 2.8, 95% confidence interval [CI] 1.5-5.2, P=.001) and SINS ≥11 (HR=2.5 , 95% CI 1.3-4.9, P=.007) were predictors of the incidence of first SAE. In propensity score matched analysis, first SAEs had developed in 22% of patients with SF RT versus 6% of those with MF RT cases (HR=3.9, 95% CI 1.6-9.6, P=.003) at 90 days after RT. Conclusion: In uncomplicated spinal metastases treated with RT alone, spinal instability with SINS ≥11 and SF RT were associated with a higher rate of SAEs.

62 RADIOLOGY AND NUCLEAR MEDICINE↗