International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
The use of adaptive radiation therapy to reduce setup error: a prospective clinical study.
Adaptive Radiation Therapy (ART) is a feedback treatment process that optimizes a patient's treatment according to the patient specific information measured during the course of treatment. Utilizing an electronic portal imaging device (EPID) and a computer-controlled multileaf collimator (MLC), the ART process is currently being implemented in our clinic to improve the treatment accuracy by compensating for the treatment setup error. A prospective study was conducted to evaluate the feasibility and efficacy of the ART process for clinical use. ⋯ The prospective study demonstrates that the ART process can be effectively implemented in routine clinical practice to improve treatment accuracy. This process is also ready to be further extended to reoptimize the treatment plan by incorporating the predicted patient specific setup variation.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
High dose-rate afterloading 192Iridium prostate brachytherapy: feasibility report.
RESULTS from localized prostate cancer series using seed implants have been most encouraging. However, with current techniques, inadequate dosimetry sometimes occurs. Remote afterloading high dose rate 192Iridium brachytherapy (HDR-Ir192) theoretically remedies some potential inadequacies of seed implantation by performing the dosimetry after the needles are in place. This study was undertaken to determine the feasibility of incorporating multifractionated HDR-Ir192 in the brachytherapy management of prostate carcinoma. ⋯ We found the use of transperineal ultrasonography, postimplant CT-based dosimetry, coupled with adjustable dose delivery inherent to remote afterloading technology, to give unparalleled control in performing this complex brachytherapy task. Thus, it may be advantageous in certain clinical situations where the resultant MPD is needed to reliably cover the target volume, such as in patients with carcinomas at base locales, when the possibility of moderate to extensive intraprostatic tumor exists, and in patients with large glands. Early PSA data suggest that it may be effective as a definitive treatment with rates of adverse late tissue effects that are acceptable using current technique and doses described herein. Longer follow-up is needed to ascertain its position among the various treatment regimens for prostate carcinoma.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
Cataracts after total body irradiation and bone marrow transplantation in patients with acute leukemia in complete remission: a study of the European Group for Blood and Marrow Transplantation.
Advances in bone marrow transplantation (BMT) have consistently improved long-term survival. Therefore, evaluation of late complications such as cataracts is of paramount importance. ⋯ High dose rate and STBI are the main risk factors for cataract development and the need for surgery, and the administration of heparin has a protective role in cataractogenesis.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
Comprehensive irradiation of head and neck cancer using conformal multisegmental fields: assessment of target coverage and noninvolved tissue sparing.
Conformal treatment using static multisegmental intensity modulation was developed for patients requiring comprehensive irradiation for head and neck cancer. The major aim is sparing major salivary gland function while adequately treating the targets. To assess the adequacy of the conformal plans regarding target coverage and dose homogeneity, they were compared with standard irradiation plans. ⋯ Planning and delivery of comprehensive irradiation for head and neck cancer using static, multisegmental intensity modulation are feasible. Target coverage has not been compromised and dose distributions in noninvolved tissue are favorable compared with standard radiation. Substantial major salivary gland function can be retained.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
Clinical TrialDose escalation with three-dimensional conformal radiation therapy affects the outcome in prostate cancer.
Three-dimensional conformal radiation therapy (3D-CRT) is a technique designed to deliver prescribed radiation doses to localized tumors with high precision, while effectively excluding the surrounding normal tissues. It facilitates tumor dose escalation which should overcome the relative resistance of tumor clonogens to conventional radiation dose levels. The present study was undertaken to test this hypothesis in patients with clinically localized prostate cancer. ⋯ The data provide evidence for a significant effect of dose escalation on the response of human prostate cancer to irradiation and defines new standards for curative radiotherapy in this disease.