International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · May 2005
Where to locate the isocenter? The treatment strategy for repeat trigeminal neuralgia radiosurgery.
The purpose of this study is to investigate how the spatial relationship between the isocenters of the first and second radiosurgeries affects the overall outcome. ⋯ Image registration between MR scans of the first and second radiosurgeries helps target delineation and radiosurgery treatment planning. Increasing the isocenter distance between the two radiosurgeries treated a longer segment of the trigeminal neuralgia nerve and was associated with a trend toward improved pain relief.
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Int. J. Radiat. Oncol. Biol. Phys. · May 2005
Longitudinal multivoxel MR spectroscopy study of pediatric diffuse brainstem gliomas treated with radiotherapy.
After radiotherapy (RT), children with diffuse intrinsic pontine gliomas (DIPG) are followed with sequential magnetic resonance imaging (MRI). However, MRI changes do not necessarily reflect tumor progression, and therefore additional noninvasive tools are needed to improve the definition of progression vs. treatment-related changes. In this study, we determined the feasibility and accuracy of multivoxel proton magnetic resonance spectroscopic imaging (1H-MRSI) for monitoring pediatric patients with DIPG. ⋯ Multivoxel MRSI is a feasible and reproducible noninvasive tool for assessing pediatric DIPG. Longitudinal multivoxel MRSI measurements have potential value in assessing response to radiation or other therapies, because they offer more coverage than single-voxel techniques and provide reliable spectral data.
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Int. J. Radiat. Oncol. Biol. Phys. · May 2005
PSA doubling time kinetics during prostate cancer biochemical relapse after external beam radiation therapy.
To investigate whether prostate-specific antigen PSA doubling time (PSADT) is constant in men with biochemical prostate cancer relapse after external beam radiotherapy (EBRT). ⋯ PSA initially rises more rapidly after AA cessation, probably because of testosterone recovery. A subgroup of patients, who received secondary intervention after treatment with radiotherapy alone, showed a change in PSADT, to a faster velocity. This greater than constant exponential PSA growth is presumably the catalyst for secondary intervention. Otherwise, PSADT did not change during prostate cancer biochemical relapse.
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Int. J. Radiat. Oncol. Biol. Phys. · May 2005
Clinical experience with chronomodulated infusional 5-fluorouracil chemoradiotherapy for pancreatic adenocarcinoma.
To evaluate retrospectively the efficacy and chronic toxicities of concurrent radiotherapy and chronomodulated infusion 5-fluorouracil (5-FU) in patients with pancreatic adenocarcinoma. ⋯ Chronomodulated 5-FU administration, based on the concept of chronotolerance, has relatively low acute toxicity. Our median survival rate was greater than that after most chemoradiotherapy programs that result in more acute toxicity. Additional study is warranted to evaluate chronomodulated radiosensitizing chemotherapy schedules in prospective trials and with attention to late effects after radiotherapy, including diabetes mellitus.
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Int. J. Radiat. Oncol. Biol. Phys. · May 2005
Why to start the concomitant boost in accelerated radiotherapy for advanced laryngeal cancer in week 3.
We analyzed toxicity and the local control rates for advanced laryngeal cancer, treated with two accelerated fractionation schedules. The main difference between the schedules was the onset of the concomitant boost, in Week 3 or Week 4. Overall treatment time and total dose were equivalent. ⋯ In our study the timing of the boost in accelerated radiotherapy for advanced laryngeal cancer was an independent factor for local control, favoring the use of a concomitant boost in Week 3. This finding may indicate that accelerated repopulation of tumor cells starts early in the treatment phase.