Chougule A, Supe S J
Department of Radiotherapy, RNT Medical College and Hospital, Udaipur, India.
Phys Med Biol. 1993 Sep;38(9):1335-42. doi: 10.1088/0031-9155/38/9/012.
Conventional radiotherapy, the five times a week regime, fails to achieve locoregional control in a large proportion of advanced carcinomas of head and neck and cervix. Different non-conventional fractionation schedules are being investigated to improve the tumour control rate but, during treatment of advanced malignancy with curative intent, it is seldom possible to deliver a radical dose to the tumour because of the constraint of inducing irreparable normal tissue complications. To compare the probability of occurrence of normal tissue damage and gain in therapeutic ratio various empirical models such as NSD, TDF, CRE and TSD have been suggested, and recently the linear quadratic (LQ) model has been gaining popularity and is claimed to be superior to earlier empirical models. We have studied twice-daily fractionated schedules in head and neck malignancy with the aim of estimating the alpha/beta value of the LQ model for early acute skin effects, and found it to be 9.16 Gy, 7.66 Gy and 8.59 Gy for mild erythema, intensive erythema and dry desquamation respectively.
传统放疗，即每周五次的放疗方案，在很大一部分晚期头颈癌和宫颈癌中未能实现局部区域控制。正在研究不同的非常规分割方案以提高肿瘤控制率，但是，在以治愈为目的治疗晚期恶性肿瘤时，由于诱导不可修复的正常组织并发症的限制，很少有可能向肿瘤给予根治性剂量。为了比较正常组织损伤发生的概率和治疗增益比，已经提出了各种经验模型，如NSD、TDF、CRE和TSD，最近线性二次（LQ）模型越来越受欢迎，并声称优于早期的经验模型。我们对头颈部恶性肿瘤每日两次分割方案进行了研究，目的是估计LQ模型早期急性皮肤反应的α/β值，发现轻度红斑、重度红斑和干性脱皮的α/β值分别为9.16 Gy、7.66 Gy和8.59 Gy。
