18Fluorodeoxyglucose PET is prognostic of progression-free and overall survival in locally advanced pancreas cancer treated with stereotactic radiotherapy.
ABSTRACT This study analyzed the prognostic value of positron emission tomography (PET) for locally advanced pancreas cancer patients undergoing stereotactic body radiotherapy (SBRT).
Fifty-five previously untreated, unresectable pancreas cancer patients received a single fraction of 25-Gy SBRT sequentially with gemcitabine-based chemotherapy. On the preradiation PET-CT, the tumor was contoured and the maximum standardized uptake value (SUVmax) and metabolic tumor burden (MTB) were calculated using an in-house software application. High-SUVmax and low-SUVmax subgroups were created by categorizing patients above or below the median SUVmax. The analysis was repeated to form high-MTB and low-MTB subgroups as well as clinically relevant subgroups with SUVmax values of <5, 5-10, or >10. Multivariate analysis analyzing SUVmax, MTB, age, chemotherapy cycles, and pretreatment carbohydrate antigen (CA)19-9 was performed.
For the entire population, median survival was 12.7 months. Median survival was 9.8 vs.15.3 months for the high- and low- SUVmax subgroups (p <0.01). Similarly, median survival was 10.1 vs. 18.0 months for the high MTB and low MTB subgroups (p <0.01). When clinical SUVmax cutoffs were used, median survival was 6.4 months in those with SUVmax >10, 9.5 months with SUVmax 5.0-10.0, and 17.7 months in those with SUVmax <5 (p <0.01). On multivariate analysis, clinical SUVmax was an independent predictor for overall survival (p = 0.03) and progression-free survival (p = 0.03).
PET scan parameters can predict for length of survival in locally advanced pancreas cancer patients.
- SourceAvailable from: Byung Il Kim[Show abstract] [Hide abstract]
ABSTRACT: Purpose Recent studies have been conducted on the relationship between fluorodeoxyglucose (FDG) uptake in F-18 FDG PET/CT and prognosis in patients with pancreatic cancer, but these studies have been carried out in small numbers of patients. The aim of this retrospective study was to determine in a large number of patients whether glucose metabolism as assessed by F-18 FDG PET/CT provides prognostic information independent of established prognostic factors in patients with pancreatic cancer. Methods We reviewed retrospectively the medical records of 165 patients (men 105, women 60, mean age 67 ± 10 years) with a diagnosis of pancreatic cancer that had undergone F-18 FDG PET/CT as part of a pretreatment workup from January 2004 to December 2009. Subsequently, all patients underwent surgery, cyberknife, radiotherapy, and/or chemotherapy. For the analysis, patients were classified by age, demographic data, maximum standardized uptake value (SUVmax), size, location, serum level of CA19-9, type of treatment, and AJCC stage. The relationship between FDG uptake and survival was analyzed using the Kaplan-Meier with log-Rank test and Cox’s proportional-hazard regression methods. Results Median survival for all 165 study subjects was 290 days and median SUV by PET/CT was 5.8 (range: 0–25.1). Patients were allocated to high (> 4.1) and low (≤4.1) SUV groups, and median survivals of these patients were 229 days and 610 days, respectively, which were significantly different (p < 0.0001). Furthermore, SUVmax was found to be significantly related to survival in each stage, i.e., there were 1267 days in stage I, 440 days in stage II, 299 days in stage III, and 143 days in stage IV (p < 0.0001). The median survival was also found to be significantly related to tumor size (p = 0.001), site (p = 0.0298), serum level of CA19-9 (p = 0.0017), distant metastasis (p < 0.0001), and type of treatment (p < 0.0001). Multivariate analysis study revealed that the patients with a low SUV (p = 0.0298), a lower serum level of CA19-9 (p = 0.0071), a lower stage (p = 0.0017), and no distant metastasis (p < 0.0001) had longer survivals. In addition, SUVmax values were found to have a similar hazard ratio of distant metastasis; it was well known predictor. Furthermore, SUVmax values showed a higher hazard ratio than that of other clinicopathologic predictors. Conclusion The present study shows that SUVmax on F-18 FDG PET/CT can provide a prognostic information in patients with pancreatic cancer.09/2012; 46(3). DOI:10.1007/s13139-012-0151-y
Conference Paper: Evolution Of Bicrystal Media Development[Show abstract] [Hide abstract]
ABSTRACT: A general review of studies on microstructure, magnetic properties and recording performance of bicrystal media grown on single crystal substrates, a NiP/Al substrate and a glass substrate is given, With similar magnetic properties, a direct experimental comparison of recording performance of CoCrPtTa /Cr/NiP films between the media with Cr (200) and Cr (110) textures on glass ceramic substrate is provided, Typically, 5-6 dB SNR improvement is observed for medium with Cr (200) texture from recording densities of 40kfci to 140kfci, Medium with Cr (200) texture has similar to 100 % bicrystal cluster microstructure and has smaller and more uniform Cr grains. A noise mechanism is discussed that relates the bicrystal microstructure to an effective random anisotropy field magnitude. Micromagnetic simulations show the latter will reduce medium noise when there is relatively large intergranular exchange coupling between the grains, However, when the intergranular exchange coupling is small, the introduction of random anisotropy field magnitude will increase the medium noise. The other noise mechainsm could be due to larger Cr grain size. A bigger magnetic cluster could be formed because more Co alloy grains on a larger Cr grain are coupled together through stronger inner intergranular exchange force, which leads to higher media noise.Magnetic Recording Conference 1996. Magnetic Recording Media., Digests of the; 09/1996
- [Show abstract] [Hide abstract]
ABSTRACT: This paper presents the first experiment performed in the frame of a French research national program in the ground transportation: ARCOS. The aim of this study is the development of an advanced cooperative system able to modify its parameters in function of the driver's behaviour. The first stage of this study consists in the building of an experiment which aims to determine the driver's behaviour during typical traffic situations without assistance tools and, from this study, to determine the variables able to differentiate various classes of comportment during an overtaking. These experimentations have been carried out on SHERPA driving simulator. 39 subjects had to drive on a combination of A-roads and B-roads, with various traffic situations. During these experimentations, drivers were filmed and variables, characteristic of vehicle position in relation to the road and of the driver's actions on the vehicle, were recorded. The Multiple Correspondence Analysis (MCA) was applied on theses variables, before hand cut into space modalities, to classify driving behaviour during different traffic situations and to identify the best set of recorded variables that allows to discriminate those classes. This article presents results of a study on the first part of a "classic" overtaking. The MCA results show that three variables are able to classify all drivers in function of their driving behaviour during this phase. In the future, the analysis of the others situations will allow to define behaviour styles of the drivers in function of traffic behaviour.Intelligent Vehicles Symposium, 2003. Proceedings. IEEE; 07/2003