International journal of radiation oncology, biology, physics
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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
Improvement in relapse-free survival throughout the PSA era in patients with localized prostate cancer treated with definitive radiotherapy: year of treatment an independent predictor of outcome.
In patients treated with radical prostatectomy in the prostate-specific antigen (PSA) era, it has been demonstrated that the year of treatment in the PSA era is associated with better pathologic parameters and outcomes, independently of other well-recognized parameters such as clinical stage, pretreatment PSA level, or Gleason score. The purpose of the present study was to study a similar phenomenon with definitive radiotherapy (RT). ⋯ When controlling for tumor, treatment, and follow-up parameters, the year in which RT was performed was still an independent predictor of outcome, consistent with observations made for radical prostatectomy patients. This indicates a more favorable presentation of localized prostate in current years probably related to a combination of factors such as screening and increased patient awareness leading to earlier diagnosis. Outcome predictions should be based on contemporaneous series.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2003
Evaluation of ultrasound-based prostate localization for image-guided radiotherapy.
To evaluate the use of the ultrasound-based BAT system for daily prostate alignment. Prostate alignments using the BAT system were compared with alignments using radiographic images of implanted radiopaque markers. The latter alignments were used as a reference. ⋯ The remaining random variability of the prostate position after the ultrasound-based alignment was similar to the initial variability. However, the occurrence of displacements >/=5 mm was reduced in the AP direction. The inter-user variation of the contour alignment process was significant.
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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.