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The use of in-vivo dosimetry in IMRT has been rare, due to the high dose gradients found in this modality. IMRT at the Radiotherapy Department of the Oncology and Radiobiology Institute (INOR) in Havana has being implemented with an aperture-based inverse planning approach. The rationale used for developing these apertures avoid small or weird shaped segments, and create a smaller number of apertures for delivery, reducing high gradient regions. A Si-diode based in vivo dosimetry system has been calibrated in terms of entrances dose for routine in vivo dosimetry in conventional applications. For IMRT QA purposes, additional calculation points are defined at d max , indicating where the entrance doses will be evaluated, and providing coordinates for placing the diodes, which are accurately positioned using the coordinates of the calculation points, obtained from the RTPS. Additional correction factor of diode response accounting for off-axis position in the beam was evaluated. IMRT test cases were implemented on a phantom to evaluate feasibility of the method for patient-specific QA. Results for evaluated points showed an average discrepancy of 0.6% (std. dev. 0.2%), demonstrating the proposed methodology can be used in the clinic for routine QA of IMRT delivery.

The electronic patient dataflow in a radiotherapy department is quite complicated. The main purpose of the computer network within the radiotherapy department is the sharing of computing resources and information (e.g. CT images, electronic portal images, isodose maps etc.). The Intranet is also used to facilitate working in groups (e.g. staff meetings). It uses TCP/IP, HTTP, and other Internet protocols and in general looks like a private version of the Internet. The purpose of this study was to create an easily accessible radiotherapy archive using Internet technology.

We describe the RAPT prototype software package for stereotactic radiotherapy treatment planning, which has been developed as part of the ESPRIT EUROPORT project for creating parallel high-performance computing (HPC) versions of commercially significant codes. This paper focuses on the parallel high-performance simulation kernel, and describes its implementation, and performance measurements for both accuracy and computation time. These show that a fully 3-D Monte-Carlo simulation, taking account of tissue inhomogeneities can be performed in around 1 hour an acceptable delay for clinical use. Every year 700,000 Europeans die of cancer, and 1.2 million contract the disease. About a quarter of the new cases each year receive radiosurgery, but 20 per cent of these treatments fail either because the tumours are not precisely located, or the irradiation does not reach every part of them. By making available an accurate simulation on a platform which is affordable by a typical, medium-sized hospital radiotherapy department, RAPT has the potential to improve treatment in many of these cases, and so to make a direct impact on patient care.

In 1979 we decided to develop a database system for the patients of the radiotherapy department. At that time the only computer suitable to do this work was the computer of radiation treatment planning. These planning computers are minicomputers with a configuration dedicated to treatment planning.

The term radiation therapy is all too readily associated with the idea of “technical medicine” and the dictates of technology, with the general human needs of the patient simply being overwhelmed. But in Erlangen, in particular, we are of the opinion that the task of the physician is not merely to provide the patient with the highest level of medical care, but also to support him as a complete and individual fellow human being. We would therefore like to report on a combined medical and pastoral training program which is probably unique in nature and which, to our minds, might serve as a model to be copied.