International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Dec 2000
Comparison of dose length, area, and volume histograms as quantifiers of urethral dose in prostate brachytherapy.
To determine the magnitude of the differences between urethral dose-volume, dose-area, and dose-length histograms (DVH, DAH, and DLH, respectively, or DgH generically). ⋯ Dose gradients in prostate implants result in the observed ordering of DAH, DVH, and DLH from higher to lower doses. The three histogram approaches remain in close agreement up to 100% of the mPD but diverge at higher doses. Although urethral point doses are the most easily determined, they underestimate the amount of urethra at risk at higher doses compared to dose area analysis. Because dosimetric parameters detailing high-dose regions such as D(10) show only slight differences between calculation methods, they are recommended over the corresponding geometric entities G(150) or G(175). The differences between the D(gg) entities are sufficiently small that they are unlikely to be of clinical significance or to confound analyses attempting to correlate urinary morbidity with urethral dosimetry.
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Int. J. Radiat. Oncol. Biol. Phys. · Dec 2000
Intensity-modulated whole pelvic radiation therapy in patients with gynecologic malignancies.
To evaluate the ability of intensity-modulated radiation therapy (IMRT) to reduce the volume of small bowel irradiated in women with gynecologic malignancies receiving whole pelvic radiotherapy (WPRT). ⋯ Our results suggest that IM-WPRT is an effective means of reducing the volume of small bowel irradiated in women with gynecologic malignancies receiving WPRT. This approach potentially offers a method for reducing small bowel complications in patients with gynecologic malignancies.
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Int. J. Radiat. Oncol. Biol. Phys. · Dec 2000
True recurrence vs. new primary ipsilateral breast tumor relapse: an analysis of clinical and pathologic differences and their implications in natural history, prognoses, and therapeutic management.
The purpose of this study was to classify all ipsilateral breast tumor relapses (IBTR) in patients treated with conservative surgery and radiation therapy (CS+RT) as either new primary tumors (NP) or true local recurrences (TR) and to assess the prognostic and therapeutic implications of this classification. ⋯ It appears that a significant portion of patients who experience ipsilateral breast tumor relapse following conservative surgery and radiation therapy have new primary tumors as opposed to true local recurrences. True recurrence and new primary tumor ipsilateral breast tumor relapses have different natural histories, different prognoses, and, in turn, different implications for therapeutic management.
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Int. J. Radiat. Oncol. Biol. Phys. · Dec 2000
Randomized Controlled Trial Multicenter Study Clinical TrialPhase II, two-arm RTOG trial (94-11) of bischloroethyl-nitrosourea plus accelerated hyperfractionated radiotherapy (64.0 or 70.4 Gy) based on tumor volume (> 20 or < or = 20 cm(2), respectively) in the treatment of newly-diagnosed radiosurgery-ineligible glioblastoma multiforme patients.
To compare survivorship, and acute and delayed toxicities following radiation therapy (RT) of radiosurgery-ineligible glioblastoma multiforme (GBM) patients treated with tumor volume-influenced, high-dose accelerated, hyperfractionated RT plus bischloroethyl-nitrosourea (BCNU), using prior RTOG malignant glioblastoma patients as historical controls. ⋯ This strategy of high-dose, accelerated hyperfractionated radiotherapy shortens overall RT treatment times while allowing dose escalation, and it provides the potential for combination with currently available, as well as newer, chemotherapy agents. Survival is comparable with previously published RTOG data, and toxicities are within acceptable limits.
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Int. J. Radiat. Oncol. Biol. Phys. · Dec 2000
Adenoviral-mediated p53 transgene expression sensitizes both wild-type and null p53 prostate cancer cells in vitro to radiation.
The effect of adenoviral-mediated p53 transgene expression on the radiation response of two human prostate cancer cell lines, the p53(wild-type) LNCaP and p53(null) PC3 lines, was examined. The objective was to determine if this vector sensitizes cells to radiation independently of their p53 status. ⋯ The clonogenic survival and apoptosis data demonstrate that p53 transgene expression sensitizes human prostate adenocarcinoma cells in vitro to irradiation. As this effect was observed in both the p53(wild-type) LNCaP and p53(null) PC3 lines, radiosensitization was independent of p53 status.