International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1996
Pulsed dose rate and fractionated high dose rate brachytherapy: choice of brachytherapy schedules to replace low dose rate treatments.
Pulsed dose rate (PDR) brachytherapy is a new type of afterloading brachytherapy (BT) in which a continuous low dose rate (LDR) treatment is simulated by a series of "pulses," i.e., fractions of short duration (less than 0.5 h) with intervals between fractions of 1 to a few hours. At the Dr. Daniel den Hoed Cancer Center, the term "PDR brachytherapy" is used for treatment schedules with a large number of fractions (at least four per day), while the term "fractionated high dose rate (HDR) brachytherapy" is used for treatment schedules with just one or two brachytherapy fractions per day. Both treatments can be applied as alternatives for LDR BT. This article deals with the choice between PDR and fractionated HDR schedules and proposes possible fractionation schedules. ⋯ Pulsed dose rate treatment schedules with longer intervals of up to 3 h appear adequate to replace LDR treatment schedules. Whether PDR schedules can, indeed, replace LDR treatment schedules and whether they offer detectable advantages over schedules with less fractionation (fractionated HDR) should be tested in clinical studies.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1996
Randomized Controlled Trial Clinical TrialEffect of interfraction interval in hyperfractionated radiotherapy with or without concurrent chemotherapy for stage III nonsmall cell lung cancer.
To explore the influence of interfraction interval in hyperfractionated radiotherapy (HFX RT) with or without concurrent chemotherapy for Stage III nonsmall cell lung cancer. ⋯ Patients treated with shorter interfraction intervals (4.5-5 h) appeared to have a better survival than those treated with longer intervals (5.5-6 h). Prospective randomized studies are warranted to further investigate the influence of interfraction interval in HFX RT.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1996
Interstitial pneumonitis following autologous bone-marrow transplantation conditioned with cyclophosphamide and total-body irradiation.
To assess the influence of different total-body irradiation (TBI) regimens on interstitial pneumonitis (IP), we retrospectively analyzed our clinical data concerning an homogeneous group of patients conditioned with cyclophosphamide (CY) alone and single-dose or fractionated TBI before autologous bone-marrow transplantation (ABMT). ⋯ This retrospective study including only the patients transplanted with ABMT conditioned with CY alone and STBI or FTBI concluded that instantaneous dose rate and age significantly influenced the incidence of IP, whereas sex, body weight, and fractionation did not.
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Int. J. Radiat. Oncol. Biol. Phys. · Jan 1996
Effect of radiation dose rate and cyclophosphamide on pulmonary toxicity after total body irradiation in a mouse model.
Interstitial pneumonitis (IP) is still a major complication after total body irradiation (TBI) and bone marrow transplantation (BMT). It is difficult to determine the exact role of radiation in this multifactorial complication, especially because most of the experimental work on lung damage was done using localized lung irradiation and not TBI. We have thus tested the effect of radiation dose rate and combining cyclophosphamide (CTX) with single fraction TBI on lung damage in a mouse model for BMT. ⋯ Lung damage following TBI could be spared using LDR. However, CTX markedly enhances TBI-induced lung damage. The combination of CTX and LDR is more toxic to the lungs than combining CTX and HDR.