International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Dec 2002
Correlation of clinical and pathologic features with outcome in patients with ductal carcinoma in situ of the breast treated with breast-conserving surgery and radiotherapy.
Although breast-conserving surgery followed by radiotherapy (RT) has become a standard treatment option for patients with ductal carcinoma in situ of the breast, risk factors for ipsilateral breast tumor recurrence (IBTR) in these patients remain an active area of investigation. The purpose of this study was to evaluate the impact of clinical and pathologic features on long-term outcome in a cohort of DCIS patients treated with breast-conserving surgery plus RT. ⋯ In this cohort of uniformly treated patients with a relatively long follow-up, the presence of necrosis was a significant predictor of local relapse. However, positive or close margin status was not a significant predictor of local relapse. Although none of the patients receiving tamoxifen had a recurrence in the ipsilateral or contralateral breast, longer follow-up is required to assess the effect of tamoxifen on these end points.
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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.