International journal of cancer. Journal international du cancer
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Comparative Study
Comparison of intensity modulated radiation therapy (IMRT) treatment techniques for nasopharyngeal carcinoma.
We studied target volume coverage and normal tissue sparing of serial tomotherapy intensity modulated radiation therapy (IMRT) and fixed-field IMRT for nasopharyngeal carcinoma (NPC), as compared with those of conventional beam arrangements. Twelve patients with NPC (T2-4N1-3M0) at Mallinckrodt Institute of Radiology underwent computed tomography simulation. Images were then transferred to a virtual simulation workstation computer for target contouring. ⋯ These encouraging dosimetric results substantiate the theoretical advantage of inverse-planning IMRT in the management of NPC. We showed that target coverage of the primary tumor was maintained and nodal coverage was improved, as compared with conventional beam arrangements. The ability of IMRT to spare the parotid glands is exciting, and a prospective clinical study is currently underway at our institution to address the optimal parotid dose-volume needs to be spared to prevent xerostomia and to improve the quality of life in patients with NPC.
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Local polymeric delivery enhances IUdR radiosensitization of human malignant gliomas (MG). The combined low-dose rate (LDR) (0.03 Gy/h) and fractionated high-dose rate (HDR) treatments result in cures of experimental MGs. To enhance efficacy, we combined polymeric IUdR delivery, LDR, and HDR for treatments of both subcutaneous and intracranial MGs. ⋯ The most striking improvement in survival followed the IUdR polymer + LDR + HDR treatment: 66.0 + 6.4 days (P < 0.05 vs. blank polymer + LDR + HDR). The polymeric IUdR delivery plus combined continuous LDR and HDR treatments results in growth delay and improved survival in animals bearing the MG xenografts. This treatment may hold promise for the treatment of human MGs.
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Previous studies with animal tumors showed that bone marrow (BM) is a privileged site where potentially lethal tumor cells are controlled in a dormant state by the immune system. Here, we investigated BM of breast cancer patients with respect to tumor cell content, immune activation status and memory T-cell content. BM-derived cells from primary operated breast cancer patients (n = 90) were compared with those from healthy donors (n = 10) and also with cells from respective blood samples. ⋯ Only some of the immunological changes seen in BM samples of cancer patients were also detectable in peripheral blood samples. Our hypothesis that BM is a special compartment for immunological memory and tumor dormancy is supported by the above findings. The overall results reveal that BM is a valuable additional compartment for immune diagnosis in pathological conditions and possibly for follow-up treatment strategies.