Clinical implications in the use of the PBC algorithm versus the AAA by comparison of different NTCP models/parameters

作     者：Bufacchi, Antonella Nardiello, Barbara Capparella, Roberto Begnozzi, Luisa 

作者机构：S Giovanni Calibita Fatebenefratelli Hosp Clin Pio11 Rome Italy S Giovanni Calibita Fatebenefratelli Hosp UOC Med Phys Rome Italy UPMC San Pietro FBF Adv Radiotherapy Ctr Rome Italy 

出 版 物：《RADIATION ONCOLOGY》 (放射肿瘤学杂志)

年 卷 期：2013年第8卷第1期

页      面：1-13页

核心收录：

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 1009[医学-特种医学] 10[医学] 

主　　题：Dose volume histogram Normal tissue complication probability Pencil beam convolution algorithm Anisotropic analytical algorithm 

摘      要：Purpose: Retrospective analysis of 3D clinical treatment plans to investigate qualitative, possible, clinical consequences of the use of PBC versus AAA. Methods: The 3D dose distributions of 80 treatment plans at four different tumour sites, produced using PBC algorithm, were recalculated using AAA and the same number of monitor units provided by PBC and clinically delivered to each patient;the consequences of the difference on the dose-effect relations for normal tissue injury were studied by comparing different NTCP model/parameters extracted from a review of published studies. In this study the AAA dose calculation is considered as benchmark data. The paired Student t-test was used for statistical comparison of all results obtained from the use of the two algorithms. Results: In the prostate plans, the AAA predicted lower NTCP value (NTCPAAA) for the risk of late rectal bleeding for each of the seven combinations of NTCP parameters, the maximum mean decrease was 2.2%. In the head-and-neck treatments, each combination of parameters used for the risk of xerostemia from irradiation of the parotid glands involved lower NTCPAAA, that varied from 12.8% (sd=3.0%) to 57.5% (sd=4.0%), while when the PBC algorithm was used the NTCPPBC s ranging was from 15.2% (sd=2.7%) to 63.8% (sd=3.8%), according the combination of parameters used;the differences were statistically significant. Also NTCPAAA regarding the risk of radiation pneumonitis in the lung treatments was found to be lower than NTCPPBC for each of the eight sets of NTCP parameters;the maximum mean decrease was 4.5%. A mean increase of 4.3% was found when the NTCPAAA was calculated by the parameters evaluated from dose distribution calculated by a convolution-superposition (CS) algorithm. A markedly different pattern was observed for the risk relating to the development of pneumonitis following breast treatments: the AAA predicted higher NTCP value. The mean NTCPAAA varied from 0.2% (sd = 0.1%) to 2.1% (sd = 0.3%), w