中文摘要：

目的探究不同病理类型肺纯磨玻璃结节（pGGN）的体积倍增时间（VDT）和净瘤质量倍增时间（nMDT）在鉴别浸润腺癌与微浸润腺癌及浸润前病变中的作用。方法回顾性分析2010年11月至2016年4月,于我院行手术切除肺部病灶的46例患者的影像和病例资料。所有患者均经病理复阅证实为肺腺癌或癌前病变，共51个pGGN，术前至少行2次CT扫描，中位随访次数3次（2~6次），中位随访时间为251 d（30~1 552 d）。根据术后病理切片复阅结果，将51个pGGN分为两大组：A组，浸润性腺癌（IAC）30例患者的30个病灶；B组，包括20例患者的21个微浸润腺癌（MIA）、原位腺癌（AIS）、非典型腺瘤性增生（AAH）病灶。利用Lung VCAR软件自动测量pGGN的体积并获得体积累积增长率和VDT，进而计算其质量、质量累积增长率和nMDT。两组间计数资料的比较采用Fisher精确概率法，计量资料的比较采用Mann-Whitney U检验，配对资料的比较采用Wilcoxon符号秩检验。采用ROC曲线分析pGGN的VDT及nMDT在鉴别IAC与MIA、AIS、AAH的最佳界值，同时计算曲线下面积（AUC）。结果51个肺pGGN的中位VDT、nMDT分别为1 854.11 d（165.22~＋∞ d）、1 138.45 d（95.92~＋∞ d），nMDT较VDT短，差异有统计学意义（Z=－2.444, P=0.015）。A组和B组的中位VDT分别为847.07 d（165.22~＋∞ d）、4 460.09 d（691.14~＋∞ d），中位nMDT分别为769.93 d（95.92~＋∞ d）、3 814.77 d（611.56~＋∞ d），A组的VDT和nMDT均较B组短，差异有统计学意义（Z值分别为－3.443和－3.860，P值均〈0.01）。鉴别IAC与MIA、AIS、AAH时，VDT的界值为2 095.86 d，敏感度和特异度分别为71.4%、80.0%；nMDT的界值为1 169.77 d，敏感度和特异度分别为81.0%、76.7%。结论肺pGGN中，IAC的VDT及nMDT均显著短于MIA、AIS、AAH。当肺pGGN的VDT〈2 095.86 d或nMDT〈1 169.77 d时，提示其病理类型为IAC的可能性大。

英文摘要：

ObjectiveTo evaluate volume doubling time （VDT） and net mass doubling time of tumor （nMDT） of pulmonary pure ground glass nodules （PGGN） of different pathological types and to investigate whether VDT and nMDT can help to differentiate invasive pulmonary adenocarcinomas from minimally invasive adenocarcinomas and preinvasive lesions.MethodsFifty-one pathologically confirmed pGGNs in 46 patients were retrospectively evaluated, in whom at least two HRCT scans were obtained preoperatively （median scan times, 3 times; range, 2—6 times） with 1-month or longer follow-up interval（median follow-up interval, 251 days; range, 30-1 552 days）. According to the rechecked results of the postoperative pathological section, 51 pGGNs were divided into two groups： group A, invasive adenocarcinoma （IAC）, 30 pGGNs （58.8%）; group B, 21 pGGNs （41.2%）, including 8 minimally invasive adenocarcinoma （MIA）, 7 adenocarcinomas in situ （AIS） and 6 atypical adenomatous hyperplasia （AAH）. The volume, cumulative percentage of volume growth and VDTs of pGGNs were automatically acquired by Lung VCAR （advantage windows 4.6, GE HealthCare）. Subsequently, the mass, cumulative percentage of mass growth and nMDTs of pGGNs were calculated. The count data and measurement data between two groups were compared using Fisher exact probability and Mann-Whitney U test, respectively. A pairwise comparision were performed by using Wilcoxon signed-rank test. Subsequently, the receiver operating characteristic （ROC） curve was used to determine the optimal cut-off values of VDT and nMDT for the differential diagnosis of IAC and MIA/AIS/AAH, and calculated the area under the curve （AUC）.ResultsThe median VDT and nMDT of 51 pGGNs were 1 854.11 days （range, 165.22—＋∞ days） and 1 138.45 days （range, 95.92—＋∞ days）, respectively. The median nMDT was shorter than the median VDT, and the difference was significant （Z=-2.444, P=0.015）. The median VDTs of IAC and MIA/AIS/AAH were 847.07 days