Wim J F Dries

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PURPOSE Treatment results for locally recurrent rectal cancers are poor. This is a result of the fact that surgery is hampered due to the severance of the anatomical planes during the primary procedure and that radiotherapy is limited by normal tissue tolerance, especially after previous irradiation. This paper describes the results of a combined treatment(More)
PURPOSE To assess the outcome of aggressive multimodality treatment with preoperative external beam radiation therapy (EBRT), extended circumferential margin excision (ECME) and intraoperative electron beam radiation therapy (IOERT) in patients with locally advanced primary rectal cancer. METHODS AND MATERIALS Thirty-eight patients with primary locally(More)
BACKGROUND AND PURPOSE It is estimated that one third of the institutes applying clinical beta sources does not perform independent dosimetry. The Netherlands commission on radiation dosimetry (NCS) recently published recommended quality control procedures and detectors for the dosimetry of beta sources. The main issues of NCS Report 14 are summarized here.(More)
In a small number of special cases it may be necessary to estimate the radiation dose to organs far away from the target volume of a patient receiving radiotherapy, e.g. the dose to the gonads or to the fetus of a pregnant patient. Previously, for external beam radiotherapy a model was developed, which enabled this estimation with acceptable accuracy for(More)
The International Commission on Radiation Units and Measurement (IRCU) 50 has clearly defined treatment volumes in radiation therapy in the management of neoplasms. These concepts are applied to the field of endovascular brachytherapy (EVBT) for the prevention of postangioplasty restenosis. The following definitions are proposed: gross target length (GTL)(More)
BACKGROUND AND PURPOSE For endovascular HDR brachytherapy, very thin sources are required and the dose is specified at a short distance to the source centre down to 1.5 mm. The source which is used in the Nucletron HDR Selectron stepping source afterloader is treated by most dose calculation algorithms in clinical use as a point source, although its(More)
BACKGROUND AND PURPOSE Brachytherapy is applied in 39 radiotherapy institutions in The Netherlands and Belgium. Each institution has its own quality control (QC) programme to ensure safe and accurate dose delivery to the patient. The main goal of this work is to gain insight into the current practice of QC of brachytherapy in The Netherlands and Belgium and(More)
The data from Meisberger et al. [Radiology 90, 953-957 (1968)] are often used as a basis for dose calculations in brachytherapy. In order to describe the absorbed dose in water around a brachytherapy point source, Meisberger provided a polynomial fit for different isotopes taking into account the effect of attenuation and scattering. The validity of the(More)
Endovascular brachytherapy is a new, rapidly growing field of interest in radiotherapy for the prevention of neointimal hyperplasia after angioplasty in both coronary and peripheral arteries. Many physics aspects of these treatments have already been addressed in the report of the American Association of Physicists in Medicine task group on 'Intravascular(More)
The treatment of large tumors such as sarcomas with intra-operative radiotherapy using a Mobetron is often complicated because of the limited field size of the primary collimator and the available applicators (max Ø100 mm). To circumvent this limitation a prototype rectangular applicator of 80 x 150 mm(2) was designed and built featuring an additional(More)