能谱CT成像联合虚拟平扫鉴别肺癌病理类型的价值研究

The Study of the Value of Spectral CT Imaging Combined with Virtual Non-Contrast in the Identification of Pathological Type of Lung Cancer

摘要: 目的：探讨能谱CT成像联合虚拟平扫鉴别肺癌病理类型的可行性。方法：前瞻性收集经病理证实的肺癌84例，所有病例术前均行能谱CT双期增强扫描。将病例分为腺癌组和鳞癌组，比较两组临床、影像特征及能谱参数的差异，能谱参数包括40~90 KeV单能量CT值、虚拟平扫CT_{70 KeV}值、ΔCT值、标准化碘浓度(NIC)、标椎化水浓度(NWC)、40~90 keV曲线斜率(λ_{40~90 keV})，并对有统计学意义的参数用ROC曲线分析，评价其诊断效能。结果：鳞癌组中男性、有吸烟史患者的比例明显高于腺癌(P < 0.05)。CT征象中，鳞癌多为中央型肺癌，腺癌多位于外周，腺癌胸膜牵拉及淋巴结肿大的发生率高于鳞癌，差异均有统计学意义(P < 0.05)。两期CT_{40~70 KeV}值、λ_{40~90 keV}、NIC、ΔCT值和动脉期CT_{80 KeV}值腺癌组高于鳞癌(P < 0.05)，而虚拟平扫CT_{70 KeV}值鳞癌组高于腺癌(P < 0.05)，静脉期NWC有统计学意义(P < 0.05)，但在两组中差别不大。ROC曲线显示能谱CT各参数诊断效能相比临床和影像更高，尤其是动脉期λ_{40~90 keV} (AUC = 0.883)。结论：能谱CT成像联合虚拟平扫在鉴别肺癌病理类型方面的临床价值较大。

Abstract: Objective: To explore the possibility of spectral CT imaging combined with virtual non-contrast in the identification of pathological type of lung cancer. Methods: 84 patients with lung cancer confirmed by pathology were prospectively collected, all patients were examined by spectral CT dual-phase enhanced scanning before surgery. The patients were divided into adenocarcinoma group and squamous cell carcinoma group, the clinical date, CT findings and spectral parameters were compared between two groups. Spectral parameters included the CT values of 40~90 KeV, virtual non-contrast CT_{70 KeV}, ΔCT value, normalized iodine concentration (NIC), normalized water concentration (NWC), the slope of 40~90 keV spectral curve (λ_{40~90 keV}), ROC curve was used on the quantitative indexes with statistical difference to evaluate the diagnostic efficacy. Results: Compared with adenocarcinoma group, male, smoking patients were more common in squamous cell carcinoma group (P < 0.05). In CT signs, most squamous cell carcinoma were central lung cancer, adenocarcinoma was more common seen in the peripheral part of the lung. In the adenocarcinoma group, the incidence of lymph node enlargement and pleural retraction were significantly higher than those in the squamous cell carcinoma group (P < 0.05). The CT values of 40~70 KeV, λ_{40~90 keV}, NIC、the value of ΔCT in two phases and the CT values of 80 KeV in the arterial phase in the adenocarcinoma group were significantly higher than those in the squamous cell carcinoma group (P < 0.05), virtual non-contrast CT_{70 KeV} of the squamous cell carcinoma group was higher than that of the adenocarcinoma group (P < 0.05), there was little difference in NWC in venous phase between two groups which had statistical difference (P < 0.05). ROC curve showed that spectral parameters had higher diagnostic efficiency than clinical and CT parameters, especially λ40~90 keV in arterial phase (AUC = 0.883). Conclusion: Spectral CT imaging combined with virtual non-contrast has a certain clinical value in the identification of pathological type of lung cancer.