International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 2001
Biology-based combined-modality radiotherapy: workshop report.
The purpose of this workshop summary is to provide an overview of preclinical and clinical data on combined-modality radiotherapy. ⋯ Cellular and molecular pathways available for radiation modification by chemical and biologic agents are numerous, providing new opportunities for translational research in radiation oncology and for more effective combined-modality treatment of cancer.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 2001
Dosimetric evaluation of lung tumor immobilization using breath hold at deep inspiration.
To examine the dosimetric benefit of self-gated radiotherapy at deep-inspiration breath hold (DIBH) in the treatment of patients with non-small-cell lung cancer (NSCLC). The relative contributions of tumor immobilization at breath hold (BH) and increased lung volume at deep inspiration (DI) in sparing high-dose lung irradiation (> or = 20 Gy) were examined. ⋯ Compared to FB conditions, at DIBH the mean reduction in percent lung volume receiving > or = 20 Gy was 14.3% with the increase in lung volume alone, 22.1% with tumor immobilization alone, and 32.5% with the combined effect. The dosimetric benefit seen at DIBH was patient specific, and due to both the increased lung volume seen at DI and the PTV margin reduction seen with tumor immobilization.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 2001
Elective nodal irradiation in the treatment of non-small-cell lung cancer with three-dimensional conformal radiation therapy.
Dose escalation using three-dimensional conformal radiation therapy (3D-CRT) has been investigated as a means to improve local control. However, with higher doses, the risk of toxicity increases. Early in our experience, we ceased treating elective nodal areas (lymph node stations without evidence of tumor involvement) in an effort to decrease toxicity while treating the gross tumor to higher doses. This report measures the rate of regional failure without elective radiation therapy to uninvolved lymph nodes. ⋯ Local control remains one of the biggest challenges in the treatment of non-small-cell lung cancer. Most patients in our series developed local failure within 2 years of radiation therapy. The omission of elective nodal treatment did not cause a significant amount of failure in lymph node regions not included in the clinical target volume. Therefore, we will continue our policy of treating mediastinal lymph node regions only if they are clinically involved with tumor.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 2001
ReviewCervical lymph node metastases from occult squamous cell carcinoma: cut down a tree to get an apple?
To review the value of extended diagnostic work-up procedures and to compare the results of comprehensive or volume-restricted radiotherapy in patients presenting with cervical lymph node metastases from clinically undetectable squamous cell carcinoma. ⋯ Physical examination, CT or MRI, and panendoscopy with biopsies remain the standard work-up for these patients. Routine use of PET or laser-induced fluorescence imaging cannot be firmly advocated based on presently available data. Although combination of nodal dissection with comprehensive radiotherapy yielded most favorable results, its impact on the quality of life should be recognized, and the confounding effects of patient selection for various treatment modalities on therapeutic outcome cannot be ruled out. A randomized trial comparing the therapeutic value of comprehensive vs. volume-limited radiotherapy is being considered.
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Int. J. Radiat. Oncol. Biol. Phys. · Jul 2001
Comparative StudyA comparison of radiation dose to the bulb of the penis in men with and without prostate brachytherapy-induced erectile dysfunction.
To retrospectively evaluate the relationship between the radiation dose to the bulb of the penis and the development of erectile dysfunction (ED) in patients undergoing permanent prostate brachytherapy without external beam radiation therapy. ⋯ Our data suggest that prostate brachytherapy-induced impotence is highly correlated with the radiation dose delivered to the bulb of the penis. With Day 0 dosimetric evaluation, the radiation dose delivered to 50% of the bulb of the penis should be maintained at 50 Gy or less to maximize post-treatment potency. Fortunately, the majority of the brachytherapy-induced ED population responds favorably to sildenafil.