International journal of radiation oncology, biology, physics
-
Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Salvage radiotherapy for rising prostate-specific antigen levels after radical prostatectomy for prostate cancer: dose-response analysis.
To investigate the association between external beam radiotherapy (EBRT) dose and biochemical failure (BcF) of prostate cancer in patients who received salvage prostate bed EBRT for a rising prostate-specific antigen (PSA) level after radical prostatectomy. ⋯ Our results suggest a dose response for salvage EBRT. Doses higher than 66.6 Gy result in decreased risk of BcF.
-
Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Review Meta AnalysisRadiation dose-volume effects in the spinal cord.
Dose-volume data for myelopathy in humans treated with radiotherapy (RT) to the spine is reviewed, along with pertinent preclinical data. Using conventional fractionation of 1.8-2 Gy/fraction to the full-thickness cord, the estimated risk of myelopathy is <1% and <10% at 54 Gy and 61 Gy, respectively, with a calculated strong dependence on dose/fraction (alpha/beta = 0.87 Gy.) Reirradiation data in animals and humans suggest partial repair of RT-induced subclinical damage becoming evident about 6 months post-RT and increasing over the next 2 years. Reports of myelopathy from stereotactic radiosurgery to spinal lesions appear rare (<1%) when the maximum spinal cord dose is limited to the equivalent of 13 Gy in a single fraction or 20 Gy in three fractions. However, long-term data are insufficient to calculate a dose-volume relationship for myelopathy when the partial cord is treated with a hypofractionated regimen.
-
Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
External beam radiotherapy for prostate cancer patients on anticoagulation therapy: how significant is the bleeding toxicity?
To characterize the bleeding toxicity associated with external beam radiotherapy for prostate cancer patients receiving anticoagulation (AC) therapy. ⋯ Patients taking AC therapy have a substantial risk of bleeding toxicity from external beam radiotherapy. In this setting, dose escalation or intensity-modulated radiotherapy should be used judiciously. With adherence to strict dose-volume histogram criteria and minimizing hotspots, the risk of severe bleeding might be reduced.
-
Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Differences in supratentorial damage of white matter in pediatric survivors of posterior fossa tumors with and without adjuvant treatment as detected by magnetic resonance diffusion tensor imaging.
To elucidate morphologic correlates of brain dysfunction in pediatric survivors of posterior fossa tumors by using magnetic resonance diffusion tensor imaging (DTI) to examine neuroaxonal integrity in white matter. ⋯ Neurotoxic mechanisms that are present in PA patients (e.g., internal hydrocephalus and damaged cerebellar structures affecting neuronal circuits) contribute significantly to the alteration of supratentorial white matter in pediatric posterior fossa tumor patients.
-
Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Late effects after radiotherapy for locally advanced cervical cancer: comparison of two brachytherapy schedules and effect of dose delivered weekly.
To compare the severe late effects (Grade 3 or greater) for two groups of cervical cancer patients treated with the same external beam radiotherapy and two high-dose-rate intracavitary brachytherapy regimens and to investigate the influence of the dose delivered each week. ⋯ To establish dose-response relationships for late complications, three-dimensional imaging and dose-volume histogram parameters are needed. We found some indications that 20 Gy/wk is an upper tolerance level when the dose to the International Commission on Radiation Units and Measurements rectum point is 81 Gy(alpha/beta=3) (isoeffective [equivalent] dose of 2-Gy fractions). However, additional investigations using three-dimensional data are needed.