International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
A preliminary study of the role of modulated electron beams in intensity modulated radiotherapy, using automated beam orientation and modality selection.
To develop an algorithm for optimal beam arrangement selection in intensity-modulated radiotherapy (IMRT) of mixed photon and electron beams. To apply this algorithm to study the utility of modulated electron beams in the context of IMRT planning. ⋯ In the two cases analyzed using the selection algorithm, the primary role of modulated electrons differs based on treatment site-normal tissue dose reduction in breast and target homogeneity improvement in head and neck. Although this preliminary study with two cases appears to suggest that the role of intensity-modulated electrons differs based on treatment site, further investigation of large numbers of cases and varied treatment sites are required to establish a definitive conclusion.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Evaluation of a contour-alignment technique for CT-guided prostate radiotherapy: an intra- and interobserver study.
The recent introduction of integrated CT/linear accelerator systems may mean that daily CT localization can become a reality in the clinic, possibly allowing further dose escalation to the prostate while limiting unwanted doses to the rectum and bladder. However, the implementation of CT localization is currently impeded by the lack of precise and robust techniques to align the treatment plan with the daily CT images. The purpose of this study was to evaluate a manual alignment technique, in which the gross target volume contours are overlaid on the daily CT images and then shifted to match the structures visible in the images. ⋯ The interobserver uncertainties associated with aligning the gross target volume contours with daily CT images were sufficiently small that this method may be used for daily CT localization of the prostate. The use of a reference image is important to improve the consistency among different users in this technique.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Clinical Trial Controlled Clinical TrialNeoadjuvant docetaxel, cisplatin, 5-fluorouracil before concurrent chemoradiotherapy in locally advanced squamous cell carcinoma of the head and neck versus concomitant chemoradiotherapy: a phase II feasibility study.
To determine the feasibility of neoadjuvant docetaxel, cisplatin, and 5-fluorouracil (TPF) followed by concurrent chemoradiotherapy (CHT-RT) compared with the same CHT-RT regimen alone in locally advanced head-and-neck squamous cell carcinoma. ⋯ Three cycles of neoadjuvant TPF followed by two cycles of PF during RT are feasible without limiting toxicity. Three cycles of TPF were well tolerated and did not compromise subsequent concomitant CHT-RT. A randomized multicenter Phase III study has been started with the aim of comparing two cycles of PF during RT as standard treatment vs. the experimental arm with three cycles of neoadjuvant TPF followed by two cycles of PF during RT.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Clinical TrialIntensity-modulated radiotherapy in treatment of pancreatic and bile duct malignancies: toxicity and clinical outcome.
To assess the efficacy and toxicity of intensity-modulated radiotherapy (IMRT) in pancreatic and bile duct (cholangiocarcinoma) malignancies. ⋯ In this hypothesis-generating analysis, the acute and chronic toxicity profile with IMRT in the treatment of pancreatic and bile duct cancer was encouraging. Local control was not compromised, despite efforts to increase conformality and avoid doses to normal structures. Distant failure remains a major obstacle in pancreatic cancer.
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Int. J. Radiat. Oncol. Biol. Phys. · Jun 2004
Intensity-modulated radiotherapy (IMRT) and concurrent capecitabine for pancreatic cancer.
Local failure continues to be a major problem in the management of pancreatic cancer. Delivery of adequate radiation doses to the pancreas is limited by radiation-sensitive normal structures in the upper abdomen. To overcome some of these restrictions, we have developed a regimen of intensity-modulated radiotherapy (IMRT) with concurrent capecitabine. ⋯ This regimen of IMRT with tumor-selective radiosensitization is well tolerated. The low toxicity profile compares favorably with that of protocols based on continuous-infusion 5-fluorouracil or gemcitabine, and the preliminary indications of efficacy are encouraging.