International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
Dose escalation with 3D conformal treatment: five year outcomes, treatment optimization, and future directions.
To report the 5-year outcomes of dose escalation with 3D conformal treatment (3DCRT) of prostate cancer. ⋯ A dose response was observed for patients with pretreatment PSA >10 ng/ml based on 5-year bNED results. No dose response was observed for patients with pretreatment PSA < 10 ng/ml. Dose response was observed for FC-LENT grade 2 and grade 3,4 GI sequelae and for LENT grade 2 GU sequelae. Optimization of treatment was made possible by the results in this report. The improvement in 5-year bNED rates for patients with PSA levels > 10 ng/ml strongly suggests that clinical trials employing radiation should investigate the use of 3DCRT and prostate doses of 76-80 Gy.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 1998
Comparative StudyChanges in biochemical disease-free survival rates as a result of adoption of the consensus conference definition in patients with clinically localized prostate cancer treated with external-beam radiotherapy.
The optimal definition of biochemical recurrence of prostate cancer after definitive radiotherapy remains elusive. Different institutions have developed their own definitions, and a consensus conference (CC) sponsored by the American Society for Therapeutic Radiology and Oncology has recently proposed another definition. This study compares the definition previously used at our institution with the definition proposed by the CC. ⋯ The CPMC definition of two PSA increases can falsely identify patients as failures, particularly if the increases in PSA are small (i.e., < or = 0.3 ng/ml). The CC definition requiring three increases in PSA can falsely identify patients as disease-free when the time to failure is long relative to the follow-up time. We propose a that a definition that combines aspects of both definitions (two consecutive increases in PSA over 3 months, with a final value greater than 1.0 ng/ml and each increase being at least 0.3 ng/ml, or three consecutive increases) may be a better definition of biochemical failure.
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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
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.