International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2004
Recovery from sublethal damage during intermittent exposures in cultured tumor cells: implications for dose modification in radiosurgery and IMRT.
In stereotactic irradiation using a linear accelerator and intensity-modulated radiation therapy (IMRT), radiation is administered intermittently, and 30 min or longer is often required in one treatment session. The purpose of the present study was to determine how different the dose delivered with such intermissions is from that delivered continuously and to estimate dose-modifying factors. ⋯ The effects of stereotactic radiosurgery and IMRT that require considerably long beam interruption (e.g., 8 min or longer in total) may be less than those of the same dose administered continuously. In treatments that take 20 min or longer, dose modification appears necessary based on biologically estimated dose-modifying factors.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2004
Randomized Controlled Trial Clinical TrialPhase III randomized trial comparing LDR and HDR brachytherapy in treatment of cervical carcinoma.
Intracavitary brachytherapy plays an important role in the treatment of cervical carcinoma. Previous results have shown controversy between the effect of dose rate on tumor control and the occurrence of complications. We performed a prospective randomized clinical trial to compare the clinical outcomes between low-dose-rate (LDR) and high-dose-rate (HDR) intracavitary brachytherapy for treatment of invasive uterine cervical carcinoma. ⋯ Comparable outcomes were demonstrated between LDR and HDR intracavitary brachytherapy. Concerning patient convenience, the lower number of medical personnel needed, and decreased radiation to health care workers, HDR intracavitary brachytherapy is an alternative to conventional LDR brachytherapy. The high number of distant failure suggests that other modalities such as systemic concurrent or adjuvant chemotherapy might lower this high recurrence, especially in Stage IIB and IIIB.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2004
Clinical TrialAdjuvant therapy in pancreatic cancer: Phase I trial of radiation dose escalation with concurrent full-dose gemcitabine.
To determine the maximal tolerated dose of radiation delivered to the primary tumor bed, in combination with full-dose gemcitabine (1000 mg/m(2) weekly x 3), after resection of pancreatic cancer. ⋯ The results of our study indicate that the maximal tolerated radiation dose, administered using conformal techniques targeted to the tumor bed, is 39 Gy. In this high-risk population, data on locoregional control suggest that the reduction in radiation dose and field size minimizes toxicity and does not result in excess failures at these sites.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2004
Androgen deprivation-induced changes in prostate anatomy predict urinary morbidity after permanent interstitial brachytherapy.
To evaluate the cytoreductive consequences of neoadjuvant androgen deprivation therapy on International Prostate Symptom Score (IPSS) normalization, catheter dependency, and the need for surgical intervention secondary to bladder outlet obstruction after permanent interstitial brachytherapy. ⋯ After neoadjuvant androgen deprivation therapy for volume reduction, some brachytherapy-related urinary morbidity parameters are highly related to the preandrogen deprivation prostate volume, variants in the TZ volume, and changes in the urethral location.
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Int. J. Radiat. Oncol. Biol. Phys. · Aug 2004
Her2/neu-positive disease does not increase risk of locoregional recurrence for patients treated with neoadjuvant doxorubicin-based chemotherapy, mastectomy, and radiotherapy.
Preclinical data suggest that overexpression of Her2/neu confers cellular radioresistance. We retrospectively studied whether Her2/neu-positive disease was associated with locoregional recurrence (LRR) after postmastectomy radiotherapy (RT) for breast cancer. ⋯ Her2/neu overexpression does not appear to predispose to LRR after neoadjuvant doxorubicin-based chemotherapy, mastectomy, and RT.