CT衰减值在鉴别不典型腺瘤样增生与原位腺癌中的价值。

The value of CT attenuation in distinguishing atypical adenomatous hyperplasia from adenocarcinoma in situ.

作者信息

Jiang Binghu, Wang Jichen, Jia Peng, Le Meizhao

机构信息

Department of Radiology, BenQ Medical Center, Nanjing 210019, China.

出版信息

Zhongguo Fei Ai Za Zhi. 2013 Nov;16(11):579-83. doi: 10.3779/j.issn.1009-3419.2013.11.03.

DOI:10.3779/j.issn.1009-3419.2013.11.03

PMID:24229623

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6000614/

Abstract

BACKGROUND AND OBJECTIVE

Advances in high-resolution computed tomography (CT) scanning have increased the detection of small ground-glass opacity (GGO) nodules and also allowed such images to be investigated in detail. However, it is difficult to differentiate atypical adenomatous hyperplasia (AAH) from adenocarcinoma in situ (AIS) with CT, even at follow-up, because they share many similar CT manifestations. While AAH is thought to be a precursor or even an early-stage lesion of lung adenocarcinoma, and the stepwise progression from AAH to AIS is thought to be reasonable. Therefore, the hypothesis that the attenuation of GGO is increased gradually from AAH to AIS is proposed. The aim of this study was to distinguish AAH from AIS with CT attenuation in patients with pure GGO nodules.

METHODS

Between January 2010 and December 2012, the CT findings in terms of the greatest diameter and mean CT attenuation (HU) were reviewed and correlated with pathology in 56 patients with AAH (n=21) and non-mucinous AIS (n=38) by two independent observers. All the 59 lesions were pure GGO nodules with size of 2 cm or smaller. To determine variability of measuring CT attenuation, we calculated the 95% confidence interval (CI) for the limits of agreement by using Bland-Altman analysis. Student t test was used to compare AAH and AIS in terms of diameter and CT attenuation. And receiver operating characteristic (ROC) curve was used to determine the optimal cut-off value of mean CT attenuation for differentiating AAH from AIS and obtain the diagnostic value. Two-tailed P value of less than 0.05 was considered to be significant.

RESULTS

For the manually measured CT attenuation, the 95%CI for the limits of agreement was -40 HU, 50 HU for inter-observer variability. Although there was significant difference in nodule diameter between AAH and AIS (P=0.046), the overlap was considerable. The mean CT attenuation was (-718 ± 53) HU (95%CI: -822, -604) for AAH, which was significantly smaller than (-600 ± 35) HU (95%CI: -669, -531) for AIS (P=0.013). The area under curve (AUC) from ROC was 0.903 for differentiating AAH from AIS, and the cut-off value of -632 HU was optimal for differentiation between AAH and AIS, with sensitivity of 0.79, specificity of 0.95, and accuracy of 0.85.

CONCLUSIONS

The mean CT attenuation can help the radiological differentiation between AAH and AIS.

摘要

背景与目的

高分辨率计算机断层扫描（CT）技术的进步提高了对小磨玻璃密度（GGO）结节的检测能力，并且能够对这类影像进行详细研究。然而，即使在随访过程中，通过CT也很难区分非典型腺瘤样增生（AAH）和原位腺癌（AIS），因为它们有许多相似的CT表现。虽然AAH被认为是肺腺癌的前驱病变甚至是早期病变，且认为从AAH到AIS是逐步进展的。因此，提出了GGO的衰减从AAH到AIS逐渐增加的假说。本研究的目的是通过CT衰减来区分纯GGO结节患者的AAH和AIS。

方法

在2010年1月至2012年12月期间，由两名独立观察者对56例AAH患者（n = 21）和非黏液性AIS患者（n = 38）的CT表现（最大直径和平均CT衰减值（HU））进行回顾，并与病理结果进行对照。所有59个病灶均为大小2 cm或更小的纯GGO结节。为确定测量CT衰减的可变性，我们使用Bland-Altman分析计算一致性界限的95%置信区间（CI）。采用学生t检验比较AAH和AIS在直径和CT衰减方面的差异。并使用受试者操作特征（ROC）曲线确定区分AAH和AIS的平均CT衰减的最佳截断值，并获得诊断价值。双侧P值小于0.0被认为具有统计学意义。

结果

对于手动测量的CT衰减，观察者间可变性的一致性界限的95%CI为-40 HU，50 HU。虽然AAH和AIS在结节直径上有显著差异（P = 0.046），但重叠部分相当大。AAH的平均CT衰减值为（-718 ± 53）HU（95%CI：-822，-604），显著低于AIS的（-600 ± 35）HU（95%CI：-669，-531）（P = 0.013）。区分AAH和AIS的ROC曲线下面积（AUC）为0.903，-632 HU的截断值最适合区分AAH和AIS，敏感性为0.79，特异性为0.95，准确性为0.85。