International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Apr 2004
Randomized Controlled Trial Clinical TrialEffects of amifostine on acute toxicity from concurrent chemotherapy and radiotherapy for inoperable non-small-cell lung cancer: report of a randomized comparative trial.
To determine the ability of amifostine to reduce the severity and/or incidence of the acute toxicities of concurrent chemotherapy and radiotherapy (RT) for non-small-cell lung cancer. ⋯ Amifostine reduced the severity and incidence of acute esophageal, pulmonary, and hematologic toxicity resulting from concurrent cisplatin-based chemotherapy and RT. Amifostine had no apparent effect on survival in these patients with unresectable non-small-cell lung cancer, suggesting that it does not have a tumor-protective effect.
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Int. J. Radiat. Oncol. Biol. Phys. · Apr 2004
Clinical TrialPhase I-II trial evaluating combined intensity-modulated radiotherapy and in situ gene therapy with or without hormonal therapy in treatment of prostate cancer-interim report on PSA response and biopsy data.
There is an evolving role for combining radiotherapy (RT) with gene therapy in the management of prostate cancer. However, the clinical results of this combined approach are much needed. The preliminary results addressing the safety of this Phase I-II study combining RT and gene therapy (adenovirus/herpes simplex virus-thymidine kinase gene/valacyclovir with or without hormonal therapy) in the treatment of prostate cancer have been previously reported. We now report the prostate-specific antigen (PSA) response and biopsy data. ⋯ This is the first reported trial of its kind in the field of prostate cancer that aims to expand the therapeutic index of RT by combining it with in situ gene therapy. The initial transient PSA rise in the Arm A patients may have been a result of local immunologic response or inflammation elicited by in situ gene therapy. Additional investigation to elucidate the mechanisms is needed. Hormonal therapy may have obliterated this rise in Arm B and C patients. The biopsy data were encouraging and appeared to show no evidence of malignancy earlier than historical data. Combined RT, short-course hormonal therapy, and in situ therapy appeared to provide good locoregional control but inadequate systemic control in patients with positive pelvic lymph nodes. Longer term use of hormonal therapy in addition to gene therapy and RT has been adopted for this group of patients to maximize both locoregional and systemic control.
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Int. J. Radiat. Oncol. Biol. Phys. · Apr 2004
Multicenter Study Clinical TrialFeasibility of neurocognitive outcome evaluations in patients with brain metastases in a multi-institutional cooperative group setting: results of Radiation Therapy Oncology Group trial BR-0018.
A multi-institutional trial was conducted by the Radiation Therapy Oncology Group (RTOG) to test the feasibility of performing a test battery consisting of five neurocognitive measures and a quality-of-life instrument in patients with brain metastases. ⋯ Neurocognitive evaluation of patients with brain metastases in a multi-institutional and cooperative group setting is feasible using the test battery and certification process used in this study. This battery and certification process will be incorporated into future RTOG brain tumor trials.
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Int. J. Radiat. Oncol. Biol. Phys. · Apr 2004
A treatment planning comparison of intensity modulated photon and proton therapy for paraspinal sarcomas.
A comparative treatment planning study has been undertaken between intensity modulated (IM) photon therapy and IM proton therapy (IMPT) in paraspinal sarcomas, so as to assess the potential benefits and limitations of these treatment modalities. In the case of IM proton therapy, plans were compared also for two different sizes of the pencil beam. Finally, a 10% and 20% dose escalation with IM protons was planned, and the consequential organ at risk (OAR) irradiation was evaluated. ⋯ These results suggest that the use of IM photon therapy, when compared to IM protons, can result in similar levels of tumor conformation. IM proton therapy, however, reduces the OAR integral dose substantially, compared to IM photon radiation therapy. As a result, tumor dose escalation was always possible with IM proton planning, within the maximal OAR dose constraints. In IM proton planning, reducing the size of the proton pencil beam (using the "mini-beam") improved the dose homogeneity, but it did not have a significant effect on the dose conformity.
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Int. J. Radiat. Oncol. Biol. Phys. · Apr 2004
Dose-volume conundrum for response of prostate cancer to brachytherapy: summary dosimetric measures and their relationship to tumor control probability.
Although it is known that brachytherapy dose distributions are highly heterogeneous, the effect of particular dose distribution patterns on tumor control probability (TCP) is unknown. It is unlikely that clinical results will throw light on the question in the near future, given the long follow-up and detailed dosimetry required for each patient. We used detailed dose distribution data from 50 patients combined with radiobiologic parameters consistent with what is known about TCP curves for prostate cancer to study the changes in TCP that accompany gross dosimetric measures and particular dosing irregularities (e.g., moderate underdosing of large volumes vs. extreme underdosing of small volumes). ⋯ The work described here was an hypothesis-generating study. Our results showed that even if the V100 and D90 are nearly identical for 2 patients, there can be (and frequently are) significant differences in the dose distributions in the subvolumes of the prostate. Under simulated dose-response conditions (i.e., with variations in the dose distribution), the D90 and minimal dose significantly affected the TCP but the V100 and the volumes moderately or severely underdosed did not. In general, one must consider the totality of the dose distribution to evaluate the dosimetric quality of a low-dose-rate prostate implant. TCP is not a monotonic function of extreme or moderate underdosing. In some instances, extreme underdosing of relatively small volumes may result in a greater TCP than moderate underdosing of relatively large volumes and vice versa.