Zhu S, Li Y, Liu Z, Cao Y, Qiu R, Su J
The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei.
The First Hospital Affiliated to Chongqing University of Medical Science, Chongqing, Chongqing.
Med Phys. 2012 Jun;39(6Part13):3760. doi: 10.1118/1.4735313.
This aim was to explore the relationship between dose-volummetrics and changes of pulmonary function tests (PFTs) and provide criteria of dose-volummetrics to predict these changes of PFTs after radiotherapy with NSCLC.
Between March 2008 to November 2009,39 patients (male 30,female 9, median age 66 years) with inoperable NSCLC received definitive 3DCRT or IMRT treatment were included in this study. The GTV included primary tumor and metastasis lymph node in hilar or mediastinum, and delineated the PTV from GTV 1.5 to 2.0 centimeter outside. The prescription doses ranged from 60-68Gy with a median dose of 66Gy. The forced vital capacity(FVC), forced expiratory volume in one second (FEV1.0) and diffusion capacity of carbon monoxide(DLCO) were checked for each patient two times, one week pretreatment and 2 to 4 months after radiotherapy. dose-volummetrics of lungV10,V15,V20,V25,V30,V35,V40, lung mean dose and GTV100,GTV95, GTV90,GTV80 were analyzed. Statistical methods of Pearson and Line regression were used to determine whether correlation existed between these metrics and the changes in PFTs.
This investigation showed that FVC went down 2.4±1.6 from 77.2±18.7 to 74.1±18.5, FEV1.0 went down 5.9±3.2 from 74.1±20.5 to 70.9±20.2 P=0.065and DLCO went down 17.9±6.3 from 70.4±20.5 to 59.8±16.0 P=0.000 after radiotherapy. No correlation was found between dose-volummterics and the changes in PFTs. Excluding patients(n=15)with pretreatment atelectasis, significant correlation was retained between dose-volummetrics (lungV20,V25,V30,V35,V40, Lung mean dose and Veff) and the PFTs changes (P=0.05).Multivariate analysis showed that lung V30 was risk factor for the changes of FEV1.0 and DLCO(P=0.046 and 0.041).Furthermore analysis by stratifies, compared lung V30=18% and <18%, the dropped values of FVC, FEV1.0, DLCO were 6.9±2.5 and 4.5±1.8 P=0.061, 15.2±4.0 and 6.1±2.3 P=0.033, 22.8±2.0 and 11.6±1.4 P=0.000 respectively, showed PFTs became more worse with lungV30=18%.
lungV30 is risk factor to affect PFTs changes in patients with NSCLC excluding those who have had pretreatment atelectasis. Our funding support received from National Natural Science Foundation of China (30870743).
探讨剂量体积参数与肺功能测试（PFTs）变化之间的关系，并提供剂量体积参数标准以预测非小细胞肺癌（NSCLC）放疗后PFTs的这些变化。
2008年3月至2009年11月，本研究纳入了39例无法手术的NSCLC患者（男性30例，女性9例，中位年龄66岁），他们接受了确定性三维适形放疗（3DCRT）或调强放疗（IMRT）。大体肿瘤体积（GTV）包括原发肿瘤和肺门或纵隔转移淋巴结，并在GTV外1.5至2.0厘米勾画计划靶体积（PTV）。处方剂量范围为60 - 68Gy，中位剂量为66Gy。在放疗前一周和放疗后2至4个月，对每位患者检查两次用力肺活量（FVC）、一秒用力呼气容积（FEV1.0）和一氧化碳弥散量（DLCO）。分析肺V10、V15、V20、V25、V30、V35、V40、肺平均剂量以及GTV100、GTV95、GTV90、GTV80的剂量体积参数。采用Pearson和线性回归统计方法确定这些参数与PFTs变化之间是否存在相关性。
本研究表明，放疗后FVC从77.2±18.7下降至74.1±18.5，下降了2.4±1.6；FEV1.0从74.1±20.5下降至70.9±20.2，下降了5.9±3.2（P = 0.065）；DLCO从70.4±20.5下降至59.8±16.0，下降了17.9±6.3（P = 0.000）。未发现剂量体积参数与PFTs变化之间存在相关性。排除放疗前有肺不张的患者（n = 15）后，剂量体积参数（肺V20、V25、V30、V35、V40、肺平均剂量和有效肺容积）与PFTs变化之间存在显著相关性（P = 0.05）。多因素分析表明，肺V30是FEV1.0和DLCO变化的危险因素（P = 0.046和0.041）。进一步分层分析，比较肺V30 = 18%和<18%时，FVC、FEV1.0、DLCO的下降值分别为6.9±2.5和4.5±1.8（P = 0.061）、15.2±4.0和6.1±2.3（P = 0.033）、22.8±2.0和11.6±1.4（P = 0.000），表明肺V30 = 18%时PFTs恶化更明显。
对于排除放疗前有肺不张的NSCLC患者，肺V30是影响PFTs变化的危险因素。本研究得到中国国家自然科学基金（30870743）的资助。
