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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
DOE OSTI2011

Clinical Evaluation of an Immbolization System for Stereotactic Body Radiotherapy Using Helical Tomotherapy

In this study, a clinical evaluation of the Body Pro-Lok{sup TM} System combined with the TomoTherapy megavoltage computed tomography (MVCT) was performed for lung and liver stereotactic body radiotherapy (SBRT) to reduce interfractional setup uncertainty. Twenty patients treated with 3-5 fractions of SBRT were analyzed retrospectively. The Body Pro-Lok{sup TM} system was used in both CT simulation and during patient treatment setup. Patients were immobilized with a vacuum cushion placed posteriorly over the thoracic region, an abdominal compression plate, and a knee and foot sponge. Pretreatment MVCT scans of the TomoTherapy HI-ART II unit were fused with the planning kVCT before delivery of each fraction to determine the interfractional setup error. A total of 84 shifts were analyzed to assess the interfractional setup accuracy. Results showed that the mean interfractional setup errors and standard deviations were -0.9 {+-} 3.1 mm, 1.2 {+-} 5.5 mm, and 6.5 {+-} 2.6 mm for lateral (IEC-X), longitudinal (IEC-Y), and vertical (IEC-Z) variations, respectively. The maximum motion was 17.1 mm in the longitudinal direction. When all 3 translational coordinates were analyzed, a mean composite displacement vector of 8.2 {+-} 2.0 mm (range 4.1-11.7 mm) was obtained for all patients. Based on the findings, image-guided SBRT using the Body Pro-Lok{sup TM} system in conjunction with the MVCT of TomoTherapy is capable of minimizing interfractional setup error and improving treatment accuracy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2025

In anaerobic reactors the microbial community structure depends on feed type, with no “keystone” species tied to COD removal

Two-stage anaerobic digestion (AD) systems provide treatment for high strength wastewater with high stability and performance. Encapsulation technology can intensify AD to facilitate the separation of the solids retention time from the hydraulic retention time (HRT), offering lower HRTs, smaller reactors, and high effluent quality. To support successful deployment, however, the encapsulated community must contain all the needed microorganisms for successful treatment and be flexible enough to treat a variety of wastewaters. Here, a two-stage system was investigated in which microbial cultures were enriched on various high-strength wastewaters in suspended flow-through systems to determine how feed type influenced performance and microbial community structure. The hypothesis was that specific genera, or so-called “keystone species” would positively correlate to organic carbon degradation for a given feed, enabling construction of a well-functioning community for encapsulation. Results showed that the number of total bacteria (as 16S rRNA gene copies) did not correlate to soluble chemical oxygen demand (sCOD) removal, indicating that the community structure and/or members were important for good performance. Results also showed that feed type strongly influenced carbon removal and microbial community structure for 1st-stage fermenting communities, but not 2nd-stage methanogenic communities. In this study, the “core” community members were defined as organisms common to all of either the 1st- or 2nd-stage reactors irrespective of the feed they received and were present in at least 50% of the samples throughout the entire experiment. “Unique” community members were specific to a single feed, and hence, only present in either the 1st- or 2nd-stage reactors receiving that feed. In both 1st- and 2nd-stage communities, only one core genera and no unique genera were positively and significantly correlated to sCOD removal. Verification experiments performed with encapsulated communities showed that organisms identified in flow-through system and correlated with carbon degradation, though not significantly, seemed to be important for performance. Our results suggest that one cannot construct a community containing specific populations in lieu of enrichment. Nevertheless, a single diverse encapsulated anaerobic community should provide good (>80%) carbon removal when fed a variety of influents, if time is provided for enrichment after deployment.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2011

Percutaneous Treatment of Biliary Cast Syndrome After Orthotopic Liver Transplantation: Comparison of Mechanical Versus Hydraulic Rheolytic Cast Extraction

Purpose: Biliary cast syndrome (BCS) is the presence of casts within the intrahepatic or extrahepatic biliary system after orthotopic liver transplantation. Our work compares two percutaneous methods for BCS treatment: the mechanical cast-extraction technique (MCE) versus the hydraulic cast-extraction (HCE) technique using a rheolytic system. Materials and Methods: A total of 24 patients were included in the study. Six patients were referred for HCE, and 18 patients were treated with MCE. A statistically significant larger number of sessions was required in the MCE group (21.0, range 11 to 72 sessions) (p = 0.033). Results: Median therapy duration was shorter in the HCE group at 2.4 months (range 2 to 5) compared with 6.7 months (range 3 to 39) in the MCE group (p < 0.001). Both patient acceptance was better and costs for total therapy were 40% less in the HCE group. No significant differences where found concerning clinical and biochemical improvement or graft and patient survival. Conclusion: The use of the hydraulic rheolytic system decreased total therapy time, thereby decreasing the induced inflammation time of the biliary tree. A significant benefit of HCE has been observed in our patients when we compare our results with those of MCE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Newly Designed Y-configured Single-Catheter Stenting for the Treatment of Hilar-Type Nonanastomotic Biliary Strictures After Orthotopic Liver Transplantation

Purpose: This study was designed to introduce our novel technique of percutaneous single catheter placement into the hilar bile ducts strictures while fulfilling the purpose of bilateral biliary drainage and stenting. We investigated the efficacy and safety of the technique for the treatment of hilar nonanastomotic biliary strictures. Methods: Ten patients who were post-orthotopic liver transplantation between July 2000 and July 2010 were enrolled in this study. Percutaneous Y-configured single-catheter stenting for bilateral bile ducts combined with balloon dilation was designed as the main treatment approach. Technical success rate, clinical indicators, complications, and recurrent rate were analyzed. Results: Technical success rate was 100%. Nine of the ten patients had biochemical normalization, cholangiographic improvement, and clinical symptoms relief. None of them experienced recurrence in a median follow-up of 26 months after completion of therapy and removal of all catheters. Complications were minor and limited to two patients. The one treatment failure underwent a second liver transplantation but died of multiple system organ failure. Conclusions: Percutaneous transhepatic Y-configured single-catheter stenting into the hilar bile ducts is technically feasible. The preliminary trial of this technique combined with traditional PTCD or choledochoscopy for the treatment of hilar biliary strictures after orthotopic liver transplantation appeared to be effective and safe. Yet, further investigation is needed.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Magnetic resonance imaging as a non-invasive method for the assessment of pancreatic fibrosis (MINIMAP): a comprehensive study design from the consortium for the study of chronic pancreatitis, diabetes, and pancreatic cancer

Characteristic features of chronic pancreatitis (CP) may be absent on standard imaging studies. Quantitative Magnetic Resonance Imaging (MRI) techniques such as T{sub 1} mapping, extracellular volume (ECV) fraction, diffusion-weighted imaging (DWI) with apparent diffusion coefficient map (ADC), MR elastography (MRE), and T{sub 1}-weighted signal intensity ratio (SIR) have shown promise for the diagnosis and grading severity of CP. However, radiologists still use the Cambridge classification which is based on traditional ductal imaging alone. There is an urgent need to develop new diagnostic criteria that incorporate both parenchymal and ductal features of CP seen by MRI/MRCP. Designed to fulfill this clinical need, we present the MINIMAP study, which was funded in September 2018 by the National Institutes of Health. This is a comprehensive quantitative MR imaging study which will be performed at multiple institutions in well-phenotyped CP patient cohorts. We hypothesize that quantitative MRI/MRCP features can serve as valuable non-invasive imaging biomarkers to detect and grade CP. We will evaluate the role of T{sub 1} relaxometry, ECV, T{sub 1}-weighted gradient echo SIR, MRE, arteriovenous enhancement ratio, ADC, pancreas volume/atrophy, pancreatic fat fraction, ductal features, and pancreatic exocrine output following secretin stimulation in the assessment of CP. We will attempt to generate a multi-parametric pancreatic tissue fibrosis (PTF) scoring system. We anticipate that a quantitative scoring system may serve as a biomarker of pancreatic fibrosis; hence this imaging technique can be used in clinical practice as well as clinical trials to evaluate the efficacy of agents which may slow the progression or reverse measures of CP.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

A Pelvic Phantom for Modeling Internal Organ Motions

A pelvic phantom was developed for use in testing image-guided radiation therapy (IGRT) and adaptive applications in radiation therapy (ART) with simulating the anterior-posterior internal organ motions during prostate radiotherapy. Measurements could be done with an ionization chamber (IC) in the simulated prostate. The rectum was simulated by air-equivalent material (AEM). The volume superior to the IC placement was considered as the bladder. The extension of AEM volume could be varied. The vertical position of the IC placement could be shifted by {+-}1 cm to simulate the prostate motion parallel to the changes in bladder volume. The reality of the simulation was inspected. Three-millimeter-slice-increment computed tomography (CT) scans were taken for irradiation planning. The structure set was adapted to the phantom from a treated patient. Planning target volume was delineated according to the RTOG 0126 study. IMRT and 3D conformal radiation therapy (3D-CRT) plans were made. Prostate motion and rectum volume changes were simulated in the phantom. IC displacement was corrected by phantom shifting. The delivered dose was measured with IC in 7 cases using intensity-modulated radiation therapy (IMRT) and 3D-CRT fractions, and single square-shaped beams: anteroposterior (AP), posteroanterior (PA), and lateral (LAT). Variations from the calculated doses were slightly below 1% at IMRT and around 1% at 3D-CRT; below 4.5% at square AP beam; up to 9% at square PA beam; and around 0.5% at square LAT beam. Other authors have already shown that by using planning systems and ultrasonic and cone beam CT guidance, correction of organ motions in a real patient during prostate cancer IGRT does not have a significant dosimetric effect. The inspection of our phantom-as described here-ended with similar results. Our team suggested that our model is sufficiently realistic and can be used for IGRT and ART testing.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2013

Mechanistic Comparison between Gastric Bypass vs. Duodenal Switch with Sleeve Gastrectomy in Rat Models

Both gastric bypass (GB) and duodenal switch with sleeve gastrectomy (DS) have been widely used as bariatric surgeries, and DS appears to be superior to GB. The aim of this study was to better understand the mechanisms leading to body weight loss by comparing these two procedures in experimental models of rats. Animals were subjected to GB, DS or laparotomy (controls), and monitored by an open-circuit indirect calorimeter composed of comprehensive laboratory animal monitoring system and adiabatic bomb calorimeter. Body weight loss was greater after DS than GB. Food intake was reduced after DS but not GB. Energy expenditure was increased after either GB or DS. Fecal energy content was increased after DS but not GB. GB induced body weight loss by increasing energy expenditure, whereas DS induced greater body weight loss by reducing food intake, increasing energy expenditure and causing malabsorption in rat models.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2012

Long-Term Outcome of Transcatheter Subsegmental and Segmental Arterial Chemoemobolization Using Lipiodol for Hepatocellular Carcinoma

Purpose: To clarify the efficacy of transcatheter hepatic sub-subsegmental, subsegmental, and segmental arterial chemoembolization using lipiodol (subseg/seg lip-TACE) for hepatocellular carcinoma (HCC), long-term outcomes of patients who had been treated using subseg/seg lip-TACE alone were retrospectively examined. Materials and Methods: Subjects comprised 199 patients with HCC (T1/2/{>=}3 = 30/108/61; Child-Pugh A/B/C = 115/52/32; Japan Integrated Staging [JIS] score {<=}1/2/{>=}3 = 88/64/47) who underwent subseg/seg lip-TACE using lipiodol mixed with an anticancer drug followed by injection of gelatin sponge particles. Each patient was followed-up every 3 months, and repeat subseg/seg lip-TACE and/or conventional lip-TACE was performed in cases showing recurrence. One-, 3-, 5-, 7-, and 10-year cumulative survival rates were calculated. Subgroup analyses were performed by stratifying the population according to T-factor, Child-Pugh classification, and JIS score. Results: Median duration of follow-up was 3.8 years (range 0.2 to 16.4). Median overall survival was 3.8 years. One-, 3-, 5-, 7- and 10-year survival rates were 91.5, 66.1, 38.8, 20.3, and 9.4% for all patients, and 95.5, 76.9, 51.9, 27.9 and 20.4% for patients with JIS {<=}1, respectively. Significant survival differences were found across two subgroups of staging systems (T2 vs. T3{<=} [P = 0.0012] and JIS score {<=}1 vs. 2 [P = 0.0036]). Conclusion: This study demonstrated that subseg/seg lip-TACE is a feasible treatment for obtaining prolonged survival in patients with localized HCC showing rich vasculature. Outcomes are influenced by both tumor stage and liver function, as seen in the best prolonged survival in patients with JIS score {<=}1.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Sulforaphane prevents microcystin-LR-induced oxidative damage and apoptosis in BALB/c mice

Microcystins (MCs), the products of blooming algae Microcystis, are waterborne environmental toxins that have been implicated in the development of liver cancer, necrosis, and even fatal intrahepatic bleeding. Alternative protective approaches in addition to complete removal of MCs in drinking water are urgently needed. In our previous work, we found that sulforaphane (SFN) protects against microcystin-LR (MC-LR)-induced cytotoxicity by activating the NF-E2-related factor 2 (Nrf2)-mediated defensive response in human hepatoma (HepG2) and NIH 3T3 cells. The purpose of this study was to investigate and confirm efficacy the SFN-induced multi-mechanistic defense system against MC-induced hepatotoxicity in an animal model. We report that SFN protected against MC-LR-induced liver damage and animal death at a nontoxic and physiologically relevant dose in BALB/c mice. The protection by SFN included activities of anti-cytochrome P450 induction, anti-oxidation, anti-inflammation, and anti-apoptosis. Our results suggest that SFN may protect mice against MC-induced hepatotoxicity. This raises the possibility of a similar protective effect in human populations, particularly in developing countries where freshwaters are polluted by blooming algae. - Graphical abstract: Display Omitted Research Highlights: > SFN protected against MC-LR-induced liver damage and animal death in BALB/c mice. > The dose of SFN is at a nontoxic and physiologically relevant dose. > The protection included activities of anti-oxidation, anti-inflammation, and anti-apoptosis. > SFN may protect mice against MC-induced hepatotoxicity.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2011

Impacts of Multileaf Collimators Leaf Width on Intensity-Modulated Radiotherapy Planning for Nasopharyngeal Carcinoma: Analysis of Two Commercial Elekta Devices

We compared the impacts of multileaf collimator (MLC) widths (standard MLC width of 10 mm [SMLC] and micro-MLC width of 4 mm [MMLC]) on intensity-modulated radiotherapy (IMRT) planning for nasopharyngeal carcinoma (NPC). Ten patients with NPC were recruited in this study. In each patient's case, plans were generated with the same machine setup parameter and optimizing methods in a treatment planning system according to 2 commercial Elekta MLC devices. All of the parameters were collected from dose-volume histograms of paired plans and evaluated. The average conformity index (CI) and homogeneous index (HI) for the planning gross target volume in IMRT plans with MMLC were 0.790 {+-} 0.036 and 1.062 {+-} 0.011, respectively. Data in plans with SMLC were 0.754 {+-} 0.038 and 1.070 {+-} 0.010, respectively. The differences were statistically significant (p < 0.05). Compared with CI and HI for planning target volume in paired plans, data with MMLC obviously were better than those with SMLC (CI: 0.858 {+-} 0.026 vs. 0.850 {+-} 0.021, p < 0.05; and HI: 1.185 {+-} 0.011 vs. 1.195 {+-} 0.011, p < 0.05). However, there was no statistical significance between evaluated parameters (Dmean, Dmax, D{sub 5}, gEUD, or NTCP) for organs at risk (OARs) in the 2 paired IMRT plans. According to these two kinds of Elekta MLC devices, IMRT plans with the MMLC have significant advantages in dose coverage for the targets, with more efficiency in treatment for NPC but fail to improve dose sparing of the OARs.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2017

Fluorescence-labeled liposome accumulation in injured colon of a mouse model of T-cell transfer-mediated inflammatory bowel disease

Drug delivery systems maximize the efficacy of drugs by improving their pharmacokinetic profiles, pharmacodynamic effects, or both and reducing their adverse effects. One of the most advanced, clinically available formulations are liposome-encapsulated drugs. In this study, we aimed to determine if liposomes can selectively deliver compounds in gastrointestinal diseases. Initially, we evaluated the correlation between the diarrhea score and accumulation of fluorescence (FL)-labeled liposome using in vivo imaging systems in various disease states of an inflammatory bowel disease mouse model. The result showed that FL-labeled liposome accumulation and colon tissue weight, which reflect the disease state were highly and positively correlated. Then, to confirm the accumulation of liposomes at injured sites of the colon, we administered both FL-labeled liposomes and luminescence probes for detecting reactive oxygen species (ROS) to the mouse model. The imaging data showed that liposome accumulation tended to coincide with ROS detected sites and the correlation coefficient indicated a significantly positive correlation between liposome accumulation and ROS detection levels. Finally, we evaluated the involvement of macrophages in the uptake mechanism of the liposomes by analyzing the relationship between FL-labeled liposome accumulation and macrophage marker gene expression levels. The result showed that the expression of each macrophage marker gene and liposome accumulation showed a significant positive correlation. Therefore, the macrophages considerably contributed to the uptake mechanism of the liposomes. These data suggest that liposomes could be an attractive delivery tool for enhancing the accumulation of drug candidates through macrophages in injured colonic tissues. This approach is expected to provide new treatment options for patients with colitis.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2011

Clinical Outcomes of Intensity-Modulated Pelvic Radiation Therapy for Carcinoma of the Cervix

Purpose: To evaluate disease outcomes and toxicity in cervical cancer patients treated with pelvic intensity-modulated radiation therapy (IMRT). Methods and Materials: We included all patients with Stage I-IVA cervical carcinoma treated with IMRT at three different institutions from 2000-2007. Patients treated with extended field or conventional techniques were excluded. Intensity-modulated radiation therapy plans were designed to deliver 45 Gy in 1.8-Gy daily fractions to the planning target volume while minimizing dose to the bowel, bladder, and rectum. Toxicity was graded according to the Radiation Therapy Oncology Group system. Overall survival and disease-free survival were estimated by use of the Kaplan-Meier method. Pelvic failure, distant failure, and late toxicity were estimated by use of cumulative incidence functions. Results: The study included 111 patients. Of these, 22 were treated with postoperative IMRT, 8 with IMRT followed by intracavitary brachytherapy and adjuvant hysterectomy, and 81 with IMRT followed by planned intracavitary brachytherapy. Of the patients, 63 had Stage I-IIA disease and 48 had Stage IIB-IVA disease. The median follow-up time was 27 months. The 3-year overall survival rate and the disease-free survival rate were 78% (95% confidence interval [CI], 68-88%) and 69% (95% CI, 59-81%), respectively. The 3-year pelvic failure rate and the distant failure rate were 14% (95% CI, 6-22%) and 17% (95% CI, 8-25%), respectively. Estimates of acute and late Grade 3 toxicity or higher were 2% (95% CI, 0-7%) and 7% (95% CI, 2-13%), respectively. Conclusions: Intensity-modulated radiation therapy is associated with low toxicity and favorable outcomes, supporting its safety and efficacy for cervical cancer. Prospective clinical trials are needed to evaluate the comparative efficacy of IMRT vs. conventional techniques.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Intensity-Modulated Radiotherapy for Oral Cavity Squamous Cell Carcinoma: Patterns of Failure and Predictors of Local Control

Purpose: Few studies have evaluated the use of intensity-modulated radiotherapy (IMRT) for squamous cell carcinoma (SCC) of the oral cavity (OC). We report clinical outcomes and failure patterns for these patients. Methods and Materials: Between October 2002 and June 2009, 37 patients with newly diagnosed SCC of the OC underwent postoperative (30) or definitive (7) IMRT. Twenty-five patients (66%) received systemic therapy. The median follow-up was 38 months (range, 10-87 months). The median interval from surgery to RT was 5.9 weeks (range, 2.1-10.7 weeks). Results: Thirteen patients experienced local-regional failure at a median of 8.1 months (range, 2.4-31.9 months), and 2 additional patients experienced local recurrence between surgery and RT. Seven local failures occurred in-field (one with simultaneous nodal and distant disease) and two at the margin. Four regional failures occurred, two in-field and two out-of-field, one with synchronous metastases. Six patients experienced distant failure. The 3-year actuarial estimates of local control, local-regional control, freedom from distant metastasis, and overall survival were 67%, 53%, 81%, and 60% among postoperative patients, respectively, and 60%, 60%, 71%, and 57% among definitive patients. Four patients developed Grade {>=}2 chronic toxicity. Increased surgery to RT interval predicted for decreased LRC (p = 0.04). Conclusions: Local-regional control for SCC of the OC treated with IMRT with or without surgery remains unsatisfactory. Definitive and postoperative IMRT have favorable toxicity profiles. A surgery-to-RT interval of <6 weeks improves local-regional control. The predominant failure pattern was local, suggesting that both improvements in target delineation and radiosensitization and/or dose escalation are needed.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Helical Tomotherapy vs. Intensity-Modulated Proton Therapy for Whole Pelvis Irradiation in High-Risk Prostate Cancer Patients: Dosimetric, Normal Tissue Complication Probability, and Generalized Equivalent Uniform Dose Analysis

Purpose: To compare intensity-modulated proton therapy (IMPT) and helical tomotherapy (HT) treatment plans for high-risk prostate cancer (HRPCa) patients. Methods and Materials: The plans of 8 patients with HRPCa treated with HT were compared with IMPT plans with two quasilateral fields set up (-100{sup o}; 100{sup o}) and optimized with the Hyperion treatment planning system. Both techniques were optimized to simultaneously deliver 74.2 Gy/Gy relative biologic effectiveness (RBE) in 28 fractions on planning target volumes (PTVs)3-4 (P + proximal seminal vesicles), 65.5 Gy/Gy(RBE) on PTV2 (distal seminal vesicles and rectum/prostate overlapping), and 51.8 Gy/Gy(RBE) to PTV1 (pelvic lymph nodes). Normal tissue calculation probability (NTCP) calculations were performed for the rectum, and generalized equivalent uniform dose (gEUD) was estimated for the bowel cavity, penile bulb and bladder. Results: A slightly better PTV coverage and homogeneity of target dose distribution with IMPT was found: the percentage of PTV volume receiving {>=}95% of the prescribed dose (V{sub 95%}) was on average >97% in HT and >99% in IMPT. The conformity indexes were significantly lower for protons than for photons, and there was a statistically significant reduction of the IMPT dosimetric parameters, up to 50 Gy/Gy(RBE) for the rectum and bowel and 60 Gy/Gy(RBE) for the bladder. The NTCP values for the rectum were higher in HT for all the sets of parameters, but the gain was small and in only a few cases statistically significant. Conclusions: Comparable PTV coverage was observed. Based on NTCP calculation, IMPT is expected to allow a small reduction in rectal toxicity, and a significant dosimetric gain with IMPT, both in medium-dose and in low-dose range in all OARs, was observed.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2011

Nuclear Factor {kappa}-Light Chain-Enhancer of Activated B Cells is Activated by Radiotherapy and is Prognostic for Overall Survival in Patients With Rectal Cancer Treated With Preoperative Fluorouracil-Based Chemoradiotheraphy

Purpose: Rectal cancer is often clinically resistant to radiotherapy (RT) and identifying molecular markers to define the biologic basis for this phenomenon would be valuable. The nuclear factor {kappa}-light chain-enhancer of activated B cells (NF-{kappa}B) is a potential anti-apoptotic transcription factor that has been associated with resistance to RT in model systems. The present study was designed to evaluate NF-{kappa}B activation in patients with rectal cancer undergoing chemoradiotherapy to determine whether NF-{kappa}B activity correlates with the outcome in rectal cancer patients. Methods and Materials: A total of 22 patients underwent biopsy at multiple points in a prospective study and the data from another 50 were analyzed retrospectively. The pretreatment tumor tissue was analyzed for multiple NF-{kappa}B subunits by immunohistochemistry. Serial tumor biopsy cores were analyzed for NF-{kappa}B-regulated gene expression using reverse transcriptase polymerase chain reaction and for NF-{kappa}B subunit nuclear localization using immunohistochemistry. Results: Several NF-{kappa}B target genes (Bcl-2, cellular inhibitor of apoptosis protein [cIAP]2, interleukin-8, and tumor necrosis factor receptor-associated-1) were significantly upregulated by a single fraction of RT at 24 h, demonstrating for the first time that NF-{kappa}B is activated by RT in human rectal tumors. The baseline NF-{kappa}B p50 nuclear expression did not correlate with the pathologic response to RT. However, an increasing baseline p50 level was prognostic for overall survival (hazard ratio, 2.15; p = .040). Conclusion: NF-{kappa}B nuclear expression at baseline in rectal cancer was prognostic for overall survival but not predictive of the response to RT. Larger patient numbers are needed to assess the effect of NF-{kappa}B target gene upregulation on the response to RT. Our results suggest that NF-{kappa}B might play an important role in tumor metastasis but not to the resistance to chemoradiotherapy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Transarterial Hepatic Yttrium-90 Radioembolization in Patients with Unresectable Intrahepatic Cholangiocarcinoma: Factors Associated with Prolonged Survival

Introduction: In unresectable intrahepatic cholangiocarcinoma (ICC), systemic chemotherapy often is viewed as the only option, although efficacy is limited. Radioembolization (RE) using yttrium-90 ({sup 90}Y) microspheres is an accepted therapy for patients with hepatocellular-carcinoma or metastatic liver tumors. However, there are limited data on the value of RE in patients with ICC and few data on factors influencing prognosis. The purpose of our retrospective analysis was to establish which factors influenced time-to-progression (TTP) and overall survival (OS). Methods: Patients with unresectable ICC were treated with {sup 90}Y resin-microspheres and assessed at 3-monthly intervals. Radiologic response was evaluated by using Response Criteria in Solid Tumors (RECIST). Baseline characteristics, biochemical/clinical toxicities, and response were examined for impact on TTP and OS. Results: Thirty-four treatments were administered to 33 patients without major complications. By RECIST, 12 patients had a partial response, 17 had stable disease, and 5 had progressive disease after 3 months. The median OS was 22 months posttreatment and 43.7 months postdiagnosis. Median TTP was 9.8 months. Survival and TTP were significantly prolonged in patients with ECOG 0 (vs. ECOG 1 or 2; median OS: 29.4, 10, and 5.1 months; TTP: 17.5, 6.9, and 2.4 months), tumor burden {<=}25% (OS: 26.7 vs. 6 months; TTP: 17.5 vs. 2.3 months), or tumor response (PR or SD vs. PD; OS: 35.5, 17.7 vs. 5.7 months; TTP: 31.9, 9.8 vs. 2.5 months), respectively (P < 0.001). Conclusions: Radioembolization is an effective and safe option for patients with unresectable ICC. Predictors for prolonged survival are performance status, tumor burden, and RECIST response.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Efficacy of perfusion CT in differentiating of pancreatic ductal adenocarcinoma from mass-forming chronic pancreatitis and characterization of isoattenuating pancreatic lesions

Purpose: Multidetector computed tomography (MDCT) is routinely used in the diagnosis of pancreatic ductal adenocarcinoma (PDAC), but it may be inadequate in some cases, especially mass-forming chronic pancreatitis (MFCP) and isoattenuating pancreatic lesions. Perfusion CT (pCT) may help resolve this problem. The aim of this study was to evaluate whether pCT could help differentiating PDAC from MFCP and in characterization of isoattenuating pancreatic lesions. Materials and methods: This prospective study included 89 cases of pancreatic lesions detected by MDCT and further analyzed with pCT. Sixty-one cases with final pathological diagnosis PDAC and 12 cases with MFCP were included from the study. Blood volume (BV), blood flow (BF), mean transit time (MTT), and permeability surface area product (PS) maps were obtained. Perfusion values obtained from the lesions and normal parenchyma were compared. Results: Compared with normal parenchyma, BV, BF, PS were lower and MTT was longer in PDAC and MFCP (p < 0.05). Compared with MFCP, BV, BF, PS were lower and MTT was longer in PDAC (p < 0.001). Compared with normal parenchyma, BV, BF, PS were lower and MTT was longer in isoattenuating lesions, (p < 0.001). Cutoff values of 7.60 mL/100 mL, 64.43 mL/100 mL/min, 28.08 mL/100 mL/min for BV, BF, PS, respectively, provided 100% sensitivity and specificity and 7.47 s for MTT provided 98.3% sensitivity, 80% specificity for distinguishing PDAC from MFCP. Conclusion: pCT is a useful technology that can be helpful in overcoming the limitations of routine MDCT in diagnosing PDAC and characterization of isoattenuating lesions.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

The LACSEMS: what radiologists need to know

Endoscopic drainage is increasingly used in lieu of percutaneous or surgical drainage of pancreatitis-related fluid collections. The lumen-apposing, covered, self-expanding, metallic stent (LACSEMS) is a newly produced stent for the transmural drainage of such fluid collections. The use of LACSEMS devices requires close coordination between knowledgeable radiologic and gastrointestinal providers. We review pancreatitis-related fluid collections and show examples from our experience with LACSEMS and the appropriate case selection, planning, deployment, and follow-up for this novel device.

62 RADIOLOGY AND NUCLEAR MEDICINE↗