Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology
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Brachytherapy (BT) plays a crucial role in the management of invasive cervix cancer from stage I to IV. Intracavitary techniques are based on afterloading devices, with different types of applicators. CT and/or MRI compatible applicators allow a sectional image based approach with a better assessment of gross tumour volume (GTV) and definition and delineation of target volume (CTV) compared to traditional approaches. Accurate and reproducible delineation of GTV, CTV and PTV, as well as of critical organs has a direct impact on BT treatment planning, especially if it is possible to adapt the pear-shape isodose by optimisation using DVH analysis. When introducing a 3D image based approach for GTV and CTV assessment, there is a need for a common language to describe the concepts and to define the terms which are to be used. ⋯ As GTV and CTV for BT change significantly during treatment, time frame for assessment of GTV and CTV for BT is specified in this report: at time of diagnosis GTV(D), CTV(D) and at time of BT GTV(B), CTV(B). Furthermore, CTV for BT is defined related to risk for recurrence: high risk CTV and intermediate risk CTV. Beside verbal descriptions detailed examples are given, partly in form of schematic drawings.
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To establish an incident reporting system to (1) record and classify incidents, (2) assess the impact of incidents on patients in terms of dose errors, and (3) evaluate the effectiveness of the quality assurance checking program implemented at the Radiation Treatment Program at the Northeastern Ontario Regional Cancer Centre (NEORCC). ⋯ Human errors occur during the various stages of the complex process of radiation therapy. If uncorrected, these could lead to substantial dose errors to patients. The implementation of a quality assurance checking program can substantially reduce these human errors but never totally eliminate them.
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To assess the efficacy of salvage radiotherapy (RT) for biopsy confirmed or clinically palpable local recurrence of prostate adenocarcinoma after radical prostatectomy (RP). ⋯ The efficacy of salvage RT alone for local recurrence was limited. This study suggests a need to explore other strategies incorporating systemic therapy, and the importance of timely referral for consideration of salvage RT in patients with rising PSA after surgery.
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Clinical Trial
Strategies to reduce the systematic error due to tumor and rectum motion in radiotherapy of prostate cancer.
The goal of this work is to develop and evaluate strategies to reduce the uncertainty in the prostate position and rectum shape that arises in the preparation stage of the radiation treatment of prostate cancer. ⋯ Both the pre-treatment as well as the adaptive correction strategy reduced the systematic error in the prostate position and rectum position and shape. A smaller systematic error makes it possible to safely reduce the margin around the clinical tumor volume, so that normal tissues can be spared or the prescription dose can be escalated.
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To correlate long-term colorectal dysfunctions following radical radiotherapy for bladder or prostate cancer with clinical parameters and dose-volume histogram parameters of the small intestine, rectum, and anal canal volume. ⋯ A relationship between several late anorectal dysfunctions and dose-volume parameters from the rectum and anal canal volume was demonstrated. It is recommended to exclude the anal canal volume from the high dose-volume and to apply rectal shielding whenever possible to prevent late anorectal dysfunctions.