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Abstract Background The aim of the study is to assess the effectiveness of intensity-modulated radiotherapy (IMRT) or image-guided radiotherapy (IGRT) for the prevention of retropharyngeal nodal recurrences in locally advanced head and neck cancer. Methods A retrospective review of 76 patients with head and neck cancer undergoing concurrent chemoradiation or postoperative radiotherapy with IMRT or IGRT who were at risk for retropharyngeal nodal recurrences because of anatomic site (hypopharynx, nasopharynx, oropharynx) and/or the presence of nodal metastases was undertaken. The prevalence of retropharyngeal nodal recurrences was assessed on follow-up positron emission tomography (PET)-CT scans. Results At a median follow-up of 22 months (4–53 months), no patient developed retropharyngeal nodal recurrences. Conclusion Prophylactic irradiation of retropharyngeal lymph nodes with IMRT or IGRT provides effective regional control for individuals at risk for recurrence in these nodes.

The PHENIX online control system is responsible for the configuration, control and monitoring of the PHENIX detector data acquisition system and ancillary control hardware, and the collection and archiving of the event data. The detector consists of 11 distinct subsystems, which are distributed physically and partitioned logically while ultimately being combined into a single operating unit. The online system consists of a large number of embedded commercial and custom processors as well as custom software processes which are involved in the collection, monitoring and control of the detector and the event data. These processing elements are distributed over a diverse set of computing platforms including VME based Power PC controllers, Pentium based NT systems, and SUN Solaris SPARC processors. CORBA has been adopted as the standard communication mechanism for PHENIX online system. This paper will describe the design, implementation and use of CORBA to achieve a uniform and platform independent control environment while providing for the access, control and monitoring of the online detector elements over the distributed and diverse control environment. Synchronous and asynchronous communication issues will be discussed as well as the development of CORBA compliant components which were developed to achieve client / server isolation and deterministic system behavior. The use and interaction between JAVA based clients and C++ based CORBA servers to further achieve a platform neutral environment will be presented.

The Online Computing System (ONCS) is responsible for the overall configuration and control of the PHENIX detector system [1]. The experiment is made up of 4 spectrometer arms with a total number of 11 subdetectors, which need to be operated by a single control and monitoring system. This includes the configuration of the individual components of the readout system, as well as the control of the state of the detector's data flow. Furthermore, the ONCS system sets up the environment for the online monitoring of the detectors. The slow control of high voltages and other ancillary devices is also part of the system. The ONCS system is designed around a distributed computing model which relies on CORBA object oriented technology, the ROOT system as the backbone of the online monitoring, and EPICS for the control of the High Voltage systems. Issues regarding the use and implementation of these technologies in the ONCS system will be discussed, as well as the methods used to control the state and health of the PHENIX detector.

A retrospective review of 32 patients with stage III nonsmall cell lung cancer who underwent chemoradiation with image-guided radiotherapy (IGRT) was recorded. Acute grade 3-4 hematologic and esophageal toxicities developed in 6 and 13 patients respectively. At a median follow-up of 14.5 months, only one patient developed grade 3 pneumonitis. The median survival was estimated to be 17 months. Five patients (15%) developed loco-regional recurrences, and 17 patients (53%) distant metastases. Grade 3-4 toxicities remained significant during chemoradiation with IGRT. However, the reduced rate of severe pneumonitis despite a high tumor dose is encouraging and needs to be investigated in future prospective studies. [ABSTRACT FROM AUTHOR]

Background: To assess the tolerance of patients with small cell lung cancer undergoing chemoradiation with tomotherapy-based image-guided radiotherapy (IGRT). Materials and Methods: A retrospective review of the toxicity profile for nine patients with small cell lung cancer of the limited stage who underwent chemoradiation delivered with helical tomotherapy (HT) has been conducted. Results: Acute grade 3-4 hematologic and esophagitis toxicities developed in two and three patients respectively. One patient developed a pulmonary embolism during radiotherapy. Seven patients had weight loss ranging from 0 to 30 pounds (median: 4 pounds). Three patients had treatment breaks ranging from 2 to 12 days. At a median follow-up of 11 months (range: 2-24 months), no patients developed any radiation related toxicities such as grade 3-4 pneumonitis or other long-term complications.The median survival was estimated to be 15 months. There were two local recurrences, three mediastinal recurrences, and six distant metastases. Conclusion: Grade 3-4 toxicities remained significant during chemoradiation when radiation was delivered with tomotherapy-based IGRT. However, the absence of grade 3-4 pneumonitis is promising and the use of HT needs to be investigated in future prospective studies [ABSTRACT FROM AUTHOR]

Background: The standard of care for locally advanced anal cancer has been concurrent chemoradiation. However, conventional treatment with 3-dimensional radiotherapy is associated with significant toxicity. The feasibility of new radiotherapy techniques such as image-guided radiotherapy (IGRT) in combination with chemotherapy for the treatment of this malignancy was assessed., Patients and Methods: A retrospective review of five patients with locally advanced anal carcinoma treated with Tomotherapy-based IGRT was conducted. All the patients received concurrent chemotherapy., Results: Gastrointestinal toxicity remained the limiting factor as four patients experienced grade 3-4 enteritis requiring a break during treatment. No patient experienced grade 3-4 hematological toxicity. Despite the large tumor size, three patients achieved local control at a median follow-up of 19 months., Conclusion: Tomotherapy-based IGRT may be a promising treatment for locally advanced anal cancer and needs to be investigated in further prospective trials.

This paper presents a general framework for assessing imaging systems and image-analysis methods on the basis of therapeutic rather than diagnostic efficacy. By analogy to receiver operating characteristic (ROC) curves, it utilizes the Therapy Operating Characteristic or TOC curve, which is a plot of the probability of tumor control vs. the probability of normal-tissue complications as the overall level of a radiotherapy treatment beam is varied. The proposed figure of merit is the area under the TOC, denoted AUTOC. If the treatment planning algorithm is held constant, AUTOC is a metric for the imaging and image-analysis components, and in particular for segmentation algorithms that are used to delineate tumors and normal tissues. On the other hand, for a given set of segmented images, AUTOC can also be used as a metric for the treatment plan itself. A general mathematical theory of TOC and AUTOC is presented and then specialized to segmentation problems. Practical approaches to implementation of the theory in both simulation and clinical studies are presented. The method is illustrated with a a brief study of segmentation methods for prostate cancer.