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Purpose: To report the efficacy and late side effects(LSEs) of CT-based image-guided brachytherapy for the treatment of cervical cancer. Materials: Between 2008 and 2014, 100 patients with FIGO stage IIB-IVA cervical carcinoma were analyzed. The patients received pelvic irradiation (45-50 Gy in 25 fractions) with concurrent chemotherapy, whereas the mean prescribed EBRT dose, including initial and boost doses to positive lymph nodes, ranged from 54 to 64 Gy. Afterwards, intracavitary(IC) or combined intracavitary/interstitial(IC/IS) brachytherapy was performed using a CT-based procedure with prescribed doses of 6 or 8 Gy in 3-7 fractions. Results: The median follow-up time was 46 months. The 5-year local control, distant metastasis-free survival, and overall survival rates were 88.9%, 81.8%, 77.9%, respectively. IC/IS brachytherapy improved the HR-CTV D90 compared with IC (p0.05 for all). Thirty-seven patients (37%) had grade 2 rectal LSEs, 3(3%) had grade 3 rectal LSE. The rectum D1cc, D2cc, and D5cc values were significantly higher in patients with grades 2/3 rectal toxicity than in those with grades 0/1 (p

// Lina Zhao 1, * , Yongchun Zhou 1, * , Yunfeng Mu 1 , Guangjin Chai 1 , Feng Xiao 1 , Lina Tan 1 , Steven H. Lin 2 , Mei Shi 1 1 Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi’an, 710032, China 2 Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA * These authors have contributed equally to this work Correspondence to: Mei Shi, email: mshi82@hotmail.com Steven H. Lin, email: shlin@mdanderson.org Keywords: definitive radiotherapy, cervical esophageal cancer, failure pattern, prognostic factor, prophylactic irradiation Received: September 20, 2016 Accepted: January 29, 2017 Published: February 24, 2017 ABSTRACT Purpose: Because of the scarcity of cervical esophageal cancer (CEC), data for this disease entity is limited. We aim to evaluate the outcomes, prognostic factors and failure patterns of CEC treated by contemporary radiotherapy (RT). Methods: We retrospectively analyzed 86 CEC patients consecutively treated between 2007 and 2015 by definitive RT with or without concurrent chemotherapy. RT was mainly delivered with Intensity Modulated Irradiation Therapy (IMRT) or Volumetric-Modulated Arc Therapy (VMAT). Statistical analyses were performed on survival, prognostic factors and failure patterns. Results: The median follow-up time was 19.4 months. The 3-year overall survival (OS), local regional failure free survival (LRFFS), distant metastatic free survival (DMFS), and progression free survival (PFS) were 53.6%, 57.9%, 81.5% and 41.5%, respectively. Independent predictors for poorer OS were N stage, hoarseness and recurrent laryngeal nerve lymph node (RLN) involvement, and predictors for LRFFS were N stage and EQD2 (equivalent dose in 2 Gy fraction) to gross tumor volume (GTV), with ≥ 66Gy achieving local control of 94.7%. Patients receiving elective nodal irradiation (ENI) had better nodal regional control than those receiving involved field irradiation (IFI). 31 (36%) patients had treatment failure and 15 (17.4%), 8 (9.3%) and 14 (16.2%) patients had local, regional, and distant failure, respectively. 86.7% (13/15) local failures were within GTV, and supraclavicular region (62.5%, 5/8) was the most common regional failure site. No severe toxicities were observed. Conclusions: Our results seem to indicate that good locoregional control might be achieved for CEC with adequate radiation dose and treatment planning approaches.

Purpose: The reported data of elderly ESCC are rather limited and there is a lack of information to guide treatment decisions for elderly patients with esophageal cancer. This study aims to identify the efficacy and factors for optimal treatment approaches for elderly esophageal squamous cell carcinoma (ESCC) treated with radiotherapy (RT) alone or concurrent chemoradiation (CCRT). Methods: This study included 184 I-III elderly ESCC patients aged ≥70 years treated by oral single agent CCRT (sCCRT) or double agents CCRT (dCCRT) or RT alone at a single institution in China. RT was delivered with Intensity Modulated Irradiation Therapy (IMRT) or Volumetric-Modulated Arc Therapy (VMAT). Sequential or simultaneous integrated boost (SIB) approach was applied for GTV dose escalation. Toxicities were evaluated by criteria of Radiation Therapy Oncology Group. Statistical analyses were performed on survival and failure patterns. Results: At a median follow-up time of 15.5 months, the 2- and 3-year estimated overall survival (OS) were 43.5% and 35.2%, respectively. T and N stage, GTV dose (cutoff value 56Gy), simultaneous integrated boost (SIB) technique and CCRT were significant predictors for the outcomes. sCCRT was significantly associated with higher OS, LRFS, and DFS when compared with RT alone and no difference was observed between sCCRT and dCCRT. 44% patients experienced treatment failure, among whom 65.4% developed local failure. 81.3% local failure occurred in GTV and 70.6% regional failures occurred out of radiation field. dCCRT was the only independent prediction factor for grade ≥ 2 neutropenia and gastrointestinal reactions compared with sCCRT and RT alone. No significant difference of toxicities was observed between sCCRT and RT alone. Conclusions: Our results demonstrated that CCRT in elderly patients had significant survival benefit compared to RT alone, especially using Single oral agent. sCCRT had less toxicities compared to dCCRT, and the toxicity was similar to RT alone. GTV dose ≥ 56 Gy and SIB technique were optimal approaches for radiotherapy.

Objective: Solitary fibrous tumor is a rare tumor occurring in almost every anatomic location of human body; however, reports of malignant solitary fibrous tumor in the nasal and paranasal area are especially rare. In this report, we describe a case of non-recurrent malignant solitary fibrous tumor of the nasal and paranasal area. Methods: The patient was initially treated with nasal and paranasal tumor cytoreductive surgery, followed by post-operative three-dimensional conformal intensity modulated radiation therapy (dynamic MLC Varian 600CD Linac, inversely optimized by the Eclipse system) and stereotactic body radiation therapy to provide a radical cure for residual tumor. Results: The tumor of the nasal and paranasal area was effectively treated and the integrity of the right eye kept. There were no signs of recurrence after four and a half years of further follow-up. Conclusions: This is the first attempt to successfully combine cytoreductive surgery with intensity modulated radiation therapy and stereotactic body radiation therapy together to treat solitary fibrous tumor of the nasal and paranasal area, which may provide a potential strategy for the treatment of similar cases.

By using the truncation technology, a kind of fast incomplete generalized minimal residual (IGMRES(m)) algorithm based on the fast multipole boundary element method (FM-BEM) was proposed. The convergence theory of the IGMRES(m) algorithm was well established and the related convergence theorem was presented with proof. To further analyze its convergence condition, two numerical experiments were carried out to solve the elastic and elasto-plastic frictional contact problems. Trough the analysis of the influence of truncation index on the computational efficiency and precision, the presented method was proved to be rapidly convergent with stable process and high precision. It was especially suitable for the elastic and elasto-plastic frictional contact problems with complicated and time-consuming iterations.

To deal with Web service dynamicity and changes of application constraints in open distributed environment, a coordination model for dynamic service composition is presented. Based on the separation of concerns, there are three different categories of entities in a Web service-based application: Web service, role and coordinator. The Web service is only responsible for performing pure functional service, and carrying out the task assigned by the role; the role is an abstraction for certain properties and functionalities, responsible for binding Web service according to constraints, and actively coordinating Web service to achieve coordination requirements; the coordinator is responsible for the coordination among roles by imposing coordination policies and binding constraints. The logic separation of Web services, roles, and coordinators in the model, decouples the dependencies between the coordinators and Web services. Thus, the model shields the coordinator layer from the dynamicity of Web services. Finally, a vehicle navigation application including traffic control Web services, GPS Web services and a navigator is illustrated how the model can be used to achieve the interaction adaptation by means of dynamic composition of Web service.

A time and interaction coordination model is presented to address the dynamic changes of interaction topology and real-time constraints among autonomous entities in open distributed timing computation. Driven by events, the model distinguishes between three kinds of entities: time coordinators, interaction coordinators and computation entities, which are separated from traditional autonomous entities based on the separation of concerns. A time coordinator is responsible for controlling real-time behaviors; an interaction coordinator is to coordinate interaction and reconfigure interconnection topology among computation entities; a computation entity is only responsible for performing pure computation. An implementation framework is additionally suggested based on Java Message Service and EJB technology. Finally, an application to a vehicle navigation system is presented, including several traffic control centers, a GPS and a navigator. It illustrates how the model and the framework can be used to achieve both the interaction topology and the timing constraints.

This paper presents a modified radial basis function (RBF) neural network for pattern recognition problems, which uses a hybrid learning algorithm to adaptively adjust the structure of the network. Two strategies are used to attain the compromise between the network complexity and accuracy, one is a modified "novelty" condition to create a new neuron in the hidden layer; the other is a pruning technique to remove redundant neurons and corresponding connections. To verify the performance of the modified network, two pattern recognition simulations are completed. One is a two-class pattern recognition problem, and the other is a real-world problem, internal component recognition in the field of architecture engineering. Simulation results including final hidden neurons, error, and accuracy using the method proposed in this paper are compared with performance of radial basis functional link network, resource allocating network and RBF neural network with generalized competitive learning algorithm. And it can be concluded that the proposed network has more concise architecture, higher classifier accuracy and fewer running time.