PURPOSE: To evaluate the linear quadratic (LQ) model for hypofractionated radiotherapy within the context of predicting radiation pneumonitis (RP) and to investigate the effect if a linear (L) model in the high region (LQL model) is used. METHODS AND MATERIALS: The radiation doses used for 128 patients treated with hypofractionated radiotherapy were converted to the equivalent doses given in fractions of 2 Gy for a range of alpha/beta ratios (1 Gy to infinity) according to the LQ(L) model. For the LQL model, different cut-off values between the LQ model and the linear component were used. The Lyman model parameters were fitted to the events of RP grade 2 or higher to derive the normal tissue complication probability (NTCP). The lung dose was calculated as the mean lung dose and the percentage of lung volume (V) receiving doses higher than a threshold dose of xGy (V(x)). RESULTS: The best NTCP fit was found if the mean lung dose, or V(x), was calculated with an alpha/beta ratio of 3 Gy. The NTCP fit of other alpha/beta ratios and the LQL model were worse but within the 95% confidence interval of the NTCP fit of the LQ model with an alpha/beta ratio of 3 Gy. The V(50) NTCP fit was better than the NTCP fit of lower threshold doses. CONCLUSIONS: For high fraction doses, the LQ model with an alpha/beta ratio of 3 Gy was the best method for converting the physical lung dose to predict RP. Copyright 2010 Elsevier Inc. All rights reserved.
PURPOSE: To evaluate the linear quadratic (LQ) model for hypofractionated radiotherapy within the context of predicting radiation pneumonitis (RP) and to investigate the effect if a linear (L) model in the high region (LQL model) is used. METHODS AND MATERIALS: The radiation doses used for 128 patients treated with hypofractionated radiotherapy were converted to the equivalent doses given in fractions of 2 Gy for a range of alpha/beta ratios (1 Gy to infinity) according to the LQ(L) model. For the LQL model, different cut-off values between the LQ model and the linear component were used. The Lyman model parameters were fitted to the events of RP grade 2 or higher to derive the normal tissue complication probability (NTCP). The lung dose was calculated as the mean lung dose and the percentage of lung volume (V) receiving doses higher than a threshold dose of xGy (V(x)). RESULTS: The best NTCP fit was found if the mean lung dose, or V(x), was calculated with an alpha/beta ratio of 3 Gy. The NTCP fit of other alpha/beta ratios and the LQL model were worse but within the 95% confidence interval of the NTCP fit of the LQ model with an alpha/beta ratio of 3 Gy. The V(50) NTCP fit was better than the NTCP fit of lower threshold doses. CONCLUSIONS: For high fraction doses, the LQ model with an alpha/beta ratio of 3 Gy was the best method for converting the physical lung dose to predict RP. Copyright 2010 Elsevier Inc. All rights reserved.
Authors: Vitali Moiseenko; Jimm Grimm; Ellen Yorke; Andrew Jackson; Anthony Yip; Minh-Phuong Huynh-Le; Anand Mahadevan; Kenneth Forster; Michael T Milano; Jona A Hattangadi-Gluth Journal: Cureus Date: 2020-10-05
Authors: Irma W E M van Dijk; Rob M van Os; Jeroen B van de Kamer; Nicolaas A P Franken; Helena J H van der Pal; Caro C E Koning; Huib N Caron; Cécile M Ronckers; Leontien C M Kremer Journal: J Cancer Surviv Date: 2014-06-14 Impact factor: 4.442
Authors: Gurleen Dhami; Jing Zeng; Hubert J Vesselle; Paul E Kinahan; Robert S Miyaoka; Shilpen A Patel; Ramesh Rengan; Stephen R Bowen Journal: Strahlenther Onkol Date: 2017-03-02 Impact factor: 3.621
Authors: Hesheng Wang; Mary Feng; Andrew Jackson; Randall K Ten Haken; Theodore S Lawrence; Yue Cao Journal: Int J Radiat Oncol Biol Phys Date: 2015-10-09 Impact factor: 7.038
Authors: Hannah Mary T Thomas; Jing Zeng; Howard J Lee; Balu Krishna Sasidharan; Paul E Kinahan; Robert S Miyaoka; Hubert J Vesselle; Ramesh Rengan; Stephen R Bowen Journal: Br J Radiol Date: 2019-08-12 Impact factor: 3.039