超声造影在局灶性机化性肺炎与原发性肺癌鉴别诊断中的价值

Analysis of contrast enhanced ultrasound in differential diagnosis of focal organizing pneumonia and primary lung cancer

目的探讨超声造影在鉴别诊断局灶性机化性肺炎（focal organizing pneumonia，FOP）与原发性肺癌中的应用价值。方法回顾性分析行超声造影检查并经病理确诊的23例FOP患者（FOP组）和75例原发性肺癌患者（原发性肺癌组）的常规超声及超声造影声像图资料。常规超声记录病灶大小，超声造影记录病灶造影剂到达时间（arrival time，AT）及病灶的灌注模式，并进行对比分析。构建ROC曲线，获得最佳AT临界点作为鉴别诊断参考值。结果FOP组与原发性肺癌组在性别分布及病灶大小方面差异无统计学意义（P〉0．05）。FOP组患者年龄小于原发性肺癌组（P=0．013）。超声造影显示FOP组AT小于原发性肺癌组[（6．9±2．4）s对（11．4±4．3）S，P=0．000]。造影增强后FOP组20例（87．0％）表现为树枝状离心性灌注，2例（8．7％）表现为向心性灌注，1例（4．3％）表现为均匀灌注；原发性肺癌组12例（16．0％）表现为树枝状离心性灌注，58例（77．3％）表现为向心性灌注，2例（2．7％）为均匀灌注，3例（4．0%）为不均匀灌注。两组灌注模式差异具有统计学意义（P=0．000）。另外，分别有8例FOP（34．8％）及31例原发性肺癌（41．3％）病灶中合并无灌注的坏死区（P=0．574）。依据ROC曲线分析，当取AT为8．5s时诊断效能最佳，其敏感性、特异性分别为74．7％、82．6％。结论超声造影有助于FOP与原发性肺癌的鉴别诊断。

Objective To invesitigate the application of contrast enhanced ultrasound in differentiating focal organizing pneumonia（FOP） and primary lung cancer. Methods The imaging data of 23 cases with FOP（FOP group） and 75 cases with primary lung cancer（primary lung cancer group） on conventional ultrasound and contrast enhanced ultrasound were retrospectively analyzed. The size and arrival time（AT） of the contrast agent and the enhanced pattern of the two groups were compared. ROC curve was created to determine the most accurate AT for differential diagnosis. Results There was no significant difference in the gender and the size of nodule between the two groups （P〉0.05）. The age of FOP group was younger than that of primary lung cancer group （ P = 0.013）. The AT of FOP group was much earlier than that of primary lung cancer group [（6.9± 2.4）s vs （11.4± 4.3）s, P = 0. 000]. In FOP group, 20 patients （87.0%） showed centrifugal enhancement, 2 patients （8. 7%） showed centripetal enhancement and 1 patient （4.3 % ） showed diffuse homogeneous enhancement, respectively. In primary lung cancer group, 12 patients （16.0%） showed centrifugal enhancement, 58 patients （77.3%） showed centripetal enhancement, 2 patients （2.7%） showed diffuse homogeneous enhancement and 3 patients （4.0%） showed diffuse heterogeneous enhancement, respectively. There was significant difference in the enhanced pattern between the two groups （ P = 0. 000）. Meanwhile, 8 patients in FOP group （34.8 % ） and 31 patients in primary lung cancer group （41.3%） had unenhanced region in the nodule （P = 0. 574）. ROC analysis demonstrated that AT of 8.5 s was the best cut-off value for the differential diagnosis. When AT earlier than 8.5 was taken as diagnostic criterion for FOP, the diagnositc sensitivity, specificity were 74.7% and 82.6%, respectively. Conclusions Contrast-enhanced ultrasound can provide evidence in differentiating FOP from primary lung cancer.