Miszczyk L, Tarnawski R, Składowski K
Radiotherapy Department, Institute of Oncology, M. Skłodowska-Curie Cancer Center, Glivice, Poland.
Neoplasma. 2000;47(2):133-6.
On the basis of 1,015 entrance and 863 exit dose in vivo measurements, 863 calculations of midline dose were done, and the average deviation and ranges of its value were estimated. Data of 710 advanced larynx cancers were reviewed in order to achieve dose-response relationship. Patients data were fitted directly to L-Q model using maximum likelihood estimation. In 16.5% of measurements the deviation of midline dose was larger than -5.2%. A steep dose response relationship for TCP was found. Considering -5.2% deviation of 2 Gy fraction and 72 Gy of total dose, the 17% (from 48 to 31%) decrease of TCP was found. It shows that deviations of delivered dose influence the tumor control probability and that after systematic error finding during fractionated radiotherapy the value of remaining fraction size and total dose should be modified to compensate the change of TCP.
基于1015次体内入射剂量和863次体内出射剂量测量，进行了863次中线剂量计算，并估计了其值的平均偏差和范围。回顾了710例晚期喉癌的数据，以建立剂量反应关系。使用最大似然估计将患者数据直接拟合到L-Q模型。在16.5%的测量中，中线剂量偏差大于-5.2%。发现TCP存在陡峭的剂量反应关系。考虑到2 Gy分割剂量和72 Gy总剂量的-5.2%偏差，发现TCP降低了17%（从48%降至31%）。这表明实际 delivered 剂量的偏差会影响肿瘤控制概率，并且在分次放疗中发现系统误差后，应修改剩余分次剂量大小和总剂量的值，以补偿TCP的变化。 （注：原文中“delivered”疑似拼写错误，可能是“delivered”，这里按“delivered”翻译）
