International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2003
In vivo thermoluminescence dosimetry dose verification of transperineal 192Ir high-dose-rate brachytherapy using CT-based planning for the treatment of prostate cancer.
To evaluate the potential of in vivo thermoluminescence dosimetry to estimate the accuracy of dose delivery in conformal high-dose-rate brachytherapy of prostate cancer. ⋯ Experimental results indicate that the proposed method is feasible for dose verification purposes and suggest that dose delivery in transperineal high-dose-rate brachytherapy after CT-based planning can be of acceptable accuracy.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2003
Comparative StudyPotential for reduced toxicity and dose escalation in the treatment of inoperable non-small-cell lung cancer: a comparison of intensity-modulated radiation therapy (IMRT), 3D conformal radiation, and elective nodal irradiation.
To systematically evaluate four different techniques of radiation therapy (RT) used to treat non-small-cell lung cancer and to determine their efficacy in meeting multiple normal-tissue constraints while maximizing tumor coverage and achieving dose escalation. ⋯ The use of 3D-CRT, particul mean dose, and NTCP in node-positive patients. The use of 3D-CRT, particularly with only 3 to 4 beam angles, has the ability to reduce normal-tissue toxicity, but has limited potential for dose escalation beyond the current standard in node-positive patients. IMRT is of limited additional value (compared to 3D-CRT) in node-negative cases, but is beneficial in node-positive cases and in cases with target volumes close to the esophagus. When meeting all normal-tissue constraints in node-positive patients, IMRT can deliver RT doses 25%-30% greater than 3D-CRT and 130%-140% greater than ENI. Whereas the possibility of dose escalation is severely limited with ENI, the potential for pulmonary and esophageal toxicity is clearly increased.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2003
Prognostic factors for disease-specific survival after first relapse of soft-tissue sarcoma: analysis of 402 patients with disease relapse after initial conservative surgery and radiotherapy.
To document the prognostic factors for survival of patients with soft-tissue sarcoma sustaining a first relapse after definitive treatment. ⋯ On the whole, patients whose sarcoma relapses fare poorly. However, select subgroups are potentially salvageable. Patients with an isolated local recurrence at sites other than the head and neck and deep trunk have a reasonable prospect for satisfactory outcome. Surgical resection of recurrences and metastases appears to play a major role in potential salvage.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2003
Shifting from hypofractionated to "conventionally" fractionated thoracic radiotherapy: a single institution's 10-year experience in the management of limited-stage small-cell lung cancer using concurrent chemoradiation.
To perform a retrospective review of a single institution's 10-year experience in treating limited-stage small-cell lung cancer (LS-SCLC) with a concurrent chemoradiation regimen modeled after the experimental arm of a randomized National Cancer Institute of Canada trial in which hypofractionated radiotherapy started with cycle 2 of chemotherapy. We then looked at the impact on patient outcomes of changing the RT during the course of the decade to a "conventionally" (2 Gy) fractionated regimen, with a focus on toxicity and survival rates. ⋯ Changing from a hypofractionated to a conventionally fractionated RT thoracic prescription did not alter outcomes because the survival, thoracic control, and toxicity rates were statistically similar. This suggests that the hypofractionated schedule remains practicable and should be considered in the setting of randomized clinical trials. In view of the benefits that accelerated schedules provide for both patients and cost containment, clinicians may opt to use this tolerable regimen in managing LS-SCLC. Regarding the future development of novel chemoradiation programs, the most critical factor in ensuring improved outcomes for LS-SCLC may be limiting the duration of RT and overall treatment time.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2003
Near simultaneous computed tomography image-guided stereotactic spinal radiotherapy: an emerging paradigm for achieving true stereotaxy.
To report treatment setup data from an emerging technique using near-simultaneous computed tomography (CT) image-guided stereotactic radiotherapy for the treatment of spinal and paraspinal tumors. ⋯ Preliminary experience suggests that the near-simultaneous CT image-guided verification technique can be used as a new platform technology for extracranial applications of stereotactic radiotherapy and radiosurgery to spinal and paraspinal tumors.