tailieunhanh - Báo cáo khoa học: "An investigation of intensity-modulated radiation therapy versus conventional two-dimensional and 3D-conformal radiation therapy for early stage larynx cancer"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Radiation Oncology cung cấp cho các bạn kiến thức về ngành y đề tài: An investigation of intensity-modulated radiation therapy versus conventional two-dimensional and 3D-conformal radiation therapy for early stage larynx cancer. | Gomez et al. Radiation Oncology 2010 5 74 http content 5 1 74 RADIATION ONCOLOGY RESEARCH Open Access An investigation of intensity-modulated radiation therapy versus conventional two-dimensional and 3D-conformal radiation therapy for early stage larynx cancer Daniel Gomez1 Oren Cahlon1 James Mechalakos2 Nancy Lee1 Abstract Introduction Intensity modulated radiation therapy IMRT has been incorporated at several institutions for early stage laryngeal cancer T1 T2N0M0 but its utility is controversial. Methods In three representative patients multiple plans were generated 1 Conventional 2D planning with the posterior border placed at either the anterior aspect tight plan or the mid-vertebral body loose plan 2 3D planning utilizing both and cm margins for the planning target volume PTV and 3 IMRT planning utilizing the same margins as the 3D plans. A dosimetric comparison was performed for the target volume spinal cord arytenoids and carotid arteries. The prescription dose was 6300 cGy 225 cGy fractions and the 3D and IMRT plans were normalized to this dose. Results For PTV margins of cm and cm the D95 of the 2D tight loose plans were 3781 5437 cGy and 5372 5869 cGy respectively IMRT 3D plans both 6300 cGy . With a PTV margin of cm the mean carotid artery dose was 2483 5671 5777 4049 cGy in the 2D tight 2D loose 3D and IMRT plans respectively. When the PTV was reduced to cm the the mean carotid artery dose was 2483 5671 6466 2577 cGy to the above four plans respectively. The arytenoid doses were similar between the four plans and spinal cord doses were well below tolerance. Conclusions IMRT provides a more ideal dose distribution compared to 2D treatment and 3D planning in regards to mean carotid dose. We therefore recommend IMRT in select cases when the treating physician is confident with the GTV. Introduction Larynx cancer is the most common head and neck malignancy in the United States and approximately half of these .