International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2002
Clinical TrialInterim report of toxicity from 3D conformal radiation therapy (3D-CRT) for prostate cancer on 3DOG/RTOG 9406, level III (79.2 Gy).
A prospective Phase I dose escalation study was conducted to determine the maximally tolerated radiation dose in men treated with three-dimensional conformal radiotherapy (3D-CRT) for localized prostate cancer. This is a preliminary report of toxicity at Level III (79.2 Gy) on 3D Oncology Group/Radiation Therapy Oncology Group (RTOG) 9406. ⋯ Based on excellent tolerance of 3D-CRT for stages T1 and T2 prostate cancer, further biological dose escalation has been pursued to Levels IV and V, 74 Gy and 78 Gy, respectively, at 2 Gy per day, in an attempt to reduce the total treatment duration. This trial has closed. A Phase III comparative RTOG trial is being developed to determine whether high-dose 3D-CRT improves efficacy.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2002
The importance of radiation doses to the penile bulb vs. crura in the development of postbrachytherapy erectile dysfunction.
Recent studies have implicated the proximal penis as a potential site-specific structure for radiation-related erectile dysfunction (ED). In this study, we evaluated by means of a validated patient-administered questionnaire whether radiation doses to the bulb of the penis and/or the proximal corporeal bodies were predictive for the development of brachytherapy-induced ED. ⋯ This is the first study to evaluate potency preservation and radiation doses to the proximal penis by means of a validated patient-administered quality-of-life instrument. Our data confirm prior reports that radiation doses to the proximal penis are predictive of brachytherapy-induced ED. In a stepwise linear regression analysis, the strongest predictors of potency preservation were bulb D(50), postimplant prostate CT volume, and patient age. With Day 0 dosimetric evaluation, the penile bulb D(50) and D(25) should be maintained below 40% and 60% mPD, respectively, whereas the crura D(50) and D(25) should be maintained below 40% and 28% mPD, respectively, to maximize posttreatment potency.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2002
In vitro enhancement of tumor cell radiosensitivity by a selective inhibitor of cyclooxygenase-2 enzyme: mechanistic considerations.
Selective cyclooxygenase-2 inhibitors have been reported to enhance the tumor response to radiation in vivo, but the cellular mechanisms underlying the radiosensitizing effect are not understood. In the present study, we investigated several possible mechanisms using a murine sarcoma cell culture system. ⋯ SC-236 significantly enhanced radiosensitivity of tumor cells; the magnitude of sensitivity was dependent on the drug's concentration. The likely mechanisms involve accumulation of cells in the radiosensitive G2-M phase of the cell cycle and inhibition of repair from sublethal radiation damage.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2002
Operable Stages IB and II cervical carcinomas: a retrospective study comparing preoperative uterovaginal brachytherapy and postoperative radiotherapy.
To evaluate our data concerning prognostic factors and treatment toxicity in a series of operable cervical carcinomas. ⋯ The prognosis for patients with cervical carcinoma was not influenced by the sequence of adjuvant RT (preoperative uterovaginal brachytherapy vs. postoperative RT) for Stages IB, IIA, and IIB with 1/3 proximal parametrial involvement. However, postoperative EBPRT increased the risk of late radiation complications.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2002
Quality of life in long-term survivors of oropharynx carcinoma.
To collect data on the health-related quality of life (QOL) of long-term survivors and to determine to what extent QOL might be an appropriate end point in the comparison of treatment options in oropharyngeal carcinoma. ⋯ The results of this study bring original and useful data about the QOL of long-term survivors of oropharynx carcinoma. In these patients, the QOL was significantly impaired, particularly in its psychosocial dimensions. The level of symptoms and functioning (except global QOL and emotional) was similar whatever the initial treatment. These results suggest the importance of coping processes. In a trial comparing treatment options from a long-term perspective, survival remains the most relevant end point, and a QOL evaluation should be a secondary end point. More prospective studies on QOL in head-and-neck cancer patients are needed to determine new strategies for rehabilitation management.