International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Treatment volume and dose optimization of MammoSite breast brachytherapy applicator.
Limited information has been reported on the dosimetry achieved with the MammoSite breast brachytherapy applicator. We present our results regarding the volume of treatment and a comparison of a single prescription point, single dwell position optimization technique with a six prescription point, multiple dwell position method. ⋯ The volume of normal breast tissue treated by the MammoSite device is comparable to other methods of interstitial brachytherapy that treat a 1-2-cm margin of tissue around the excision cavity. The six-prescription point, multiple dwell position method improved dose coverage with a slight decrease in dose homogeneity. The six-point method offers greater reliability of dose coverage compared with the single-point method by providing an increased number of reference points.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Comparative StudyExtended prostate biopsy scheme improves reliability of Gleason grading: implications for radiotherapy patients.
With sextant prostate biopsies, there is up to a 1-in-3 chance that the underlying pathologic Gleason grade is higher. Knowledge of the underlying grade might have significantly altered the therapeutic recommendations and management for patients electing radiotherapy for localized prostate cancer (e.g., eligibility for brachytherapy, androgen suppression with external beam radiotherapy, elective pelvic radiotherapy). This study examines the concordance patterns between biopsy and matched radical prostatectomy Gleason grade among patients undergoing an extended 10-core biopsy scheme to assess its reliability compared to sextant biopsies. ⋯ The extended 10-core biopsy scheme significantly improves on sextant biopsies in predicting the underlying pathologic Gleason score for prostate cancer. In particular, it is superior to sextant biopsies in revealing the presence of an underlying high-grade component. The potential clinical impact this improvement has for patients ultimately selecting radiotherapy suggests that an extended biopsy scheme should become the standard of care. Nevertheless, even with this improvement, there still remains up to a 1-in-5 chance that the underlying grade will be higher.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Clinical TrialEnhanced systemic T-cell activation after in situ gene therapy with radiotherapy in prostate cancer patients.
In situ cytotoxic gene therapy can potentially trigger a systemic immune response, which could impact occult metastatic disease. We are currently conducting three clinical trials using in situ adenoviral vector mediated herpes simplex virus-thymidine kinase (HSV-tk) gene delivery followed by the HSV-tk prodrug ganciclovir (GCV) or valacyclovir (VCV). This study evaluates the systemic T-cell response after gene therapy in each trial. ⋯ This is the first report of systemic T-cell responses after HSV-tk+GCV/VCV gene therapy under three clinical trial conditions. There was an increase in activated CD8+ T cells in the peripheral blood after vector injection, suggesting the potential for activation of components of cell-mediated immune response in all trial conditions. The addition of radiotherapy to in situ gene therapy seems to further increase the total CD8+ T cells and activated CD4+ T cells.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Clinical Trial Controlled Clinical TrialNeoadjuvant docetaxel, cisplatin, 5-fluorouracil before concurrent chemoradiotherapy in locally advanced squamous cell carcinoma of the head and neck versus concomitant chemoradiotherapy: a phase II feasibility study.
To determine the feasibility of neoadjuvant docetaxel, cisplatin, and 5-fluorouracil (TPF) followed by concurrent chemoradiotherapy (CHT-RT) compared with the same CHT-RT regimen alone in locally advanced head-and-neck squamous cell carcinoma. ⋯ Three cycles of neoadjuvant TPF followed by two cycles of PF during RT are feasible without limiting toxicity. Three cycles of TPF were well tolerated and did not compromise subsequent concomitant CHT-RT. A randomized multicenter Phase III study has been started with the aim of comparing two cycles of PF during RT as standard treatment vs. the experimental arm with three cycles of neoadjuvant TPF followed by two cycles of PF during RT.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Comparative StudyRadiotherapy after radical prostatectomy: does transient androgen suppression improve outcomes?
The long-term biochemical relapse-free survival and overall survival were compared for patients receiving either radiotherapy (RT) alone or radiotherapy combined with a short-course of total androgen suppression for failure after radical prostatectomy. ⋯ Radiotherapy combined with a short-course TAS after radical prostatectomy appears to confer a PSA relapse-free survival advantage and possibly an overall survival advantage when compared with RT alone. The hypothesis that a transient course of androgen suppression with salvage or adjuvant RT after prostatectomy improves outcomes will need to be tested in a randomized trial.