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: Guidelines for delineation of lymphatic clinical target volumes for high conformal radiotherapy: head and neck region. | Vorwerk and Hess Radiation Oncology 2011 6 97 http content 6 1 97 RADIATION ONCOLOGY REVIEW Open Access Guidelines for delineation of lymphatic clinical target volumes for high conformal radiotherapy head and neck region Hilke Vorwerk1 2 and Clemens F Hess1 Abstract The success of radiotherapy depends on the accurate delineation of the clinical target volume. The delineation of the lymph node regions has most impact especially for tumors in the head and neck region. The purpose of this article was the development an atlas for the delineation of the clinical target volume for patients who should receive radiotherapy for a tumor of the head and neck region. Literature was reviewed for localisations of the adjacent lymph node regions and their lymph drain in dependence of the tumor entity. On this basis the lymph node regions were contoured on transversal CT slices. The probability for involvement was reviewed and a recommendation for the delineation of the CTV was generated. Introduction The major problem in radiation treatment with IMRT technique is the failure to select and delineate the target accurately especially in patients with head and neck cancer in which a high risk of subclinical nodal disease exists. CT-based investigation is not sufficient to detect metastases smaller than one centimetre in diameter 1 . Since the lymph node status is the most important prognostic factor in patients with squamous cell cancer in the head and neck region and due to the limitation of clinical staging other factors like histopathologic examinations may help to predict metastatic lymph node involvement 1-3 . The lymphatic migration of tumor cells is usually stepwise and occurs in a predictable manner 4-6 . Detailed anatomical knowledge of the lymphatic network associated with each area of the body is essential to define all the sides in which the presence of metastatic nodes should be investigated and to delineate on a morphological basis the optimal target
