18F-FDG PET/CT在局灶性机化性肺炎诊断中的应用

Clinical application of^18F-FDG PET/CT imaging in diagnosis of focal organizing pneumonia

目的探讨局灶性机化性肺炎(FOP)^18F-脱氧葡萄糖(FDG)PET/CT[同机高分辨率(HR)CT]的影像特征。方法回顾性分析复旦大学附属中山医院2012年5月至2018年12月间因肺内孤立性实性结节行^18F-FDG PET/CT和同机HRCT检查,且术后病理证实为FOP[男33例、女12例,年龄(58±9)岁]和周围型非黏液性实性肺腺癌[男21例、女26例,年龄(63±10)岁]的患者。患者于PET/CT检查后3周内行外科手术。分析患者的影像资料,采用Mann-Whitney U或近似t检验比较FOP和肺腺癌的病灶最大标准摄取值(SUVmax)、最大径差异,对SUVmax和最大径行Spearman秩相关或Pearson相关分析,并进行二分类logsitic回归分析,以获取预测FOP的独立因子,最后行受试者工作特征(ROC)曲线分析。结果FOP的病灶SUVmax[3.1(1.7,4.9)]和最大径[(18.0±6.3)mm]均小于肺腺癌的SUVmax[6.5(3.8,9.3)]和最大径[(21.8±4.3)mm],差异均具有统计学意义(z=-4.598,t′=-3.424,均P<0.01)。FOP的SUVmax与其最大径呈正相关(rs=0.509,P<0.01),肺腺癌的SUVmax与其最大径不相关(r=0.076,P>0.05)。在同机HRCT图像上,沿支气管血管束呈梭形者更多见于FOP(χ^2=9.549,P<0.05)。二分类logistic回归分析示,病灶SUVmax、最大径和形态均为预测FOP的独立因子[比值比(OR)值:10.585、4.674、9.073,均P<0.05]。ROC曲线分析示,SUVmax≤7.1且结节最大径≤18.3 mm、形态呈梭形联合诊断FOP的曲线下面积为0.860,灵敏度、特异性、阳性预测值、阴性预测值和准确性分别为97.8%(44/45)、70.2%(33/47)、75.9%(44/58)、97.1%(33/34)和83.7%(77/92)。结论SUVmax≤7.1且结节呈梭形、最大径≤18.3 mm的实性结节多提示为FOP。

Objective To explore the imaging features of^18F-fluorodeoxyglucose(FDG)PET/CT(high-resolution CT,HRCT)imaging in focal organizing pneumonia(FOP).Methods Patients with solid nodular FOP(n=45;33 males,12 females,age(58±9)years)and early peripheral non-mucinous solid lung adenocarcinoma(n=47;21 males,26 females,age(63±10)years)confirmed by postsurgical pathology between May 2012 and December 2018 in Zhongshan Hospital,Fudan University were retrospectively analyzed.All patients underwent^18F-FDG PET/CT(HRCT)imaging followed by surgery within 3 weeks.The imaging findings and characteristics of the lesions were recorded.Differences of the maximum standardized uptake value(SUVmax)and maximum diameter between FOP and adenocarcinoma were analyzed by Mann-Whitney U test or t′test.Spearman correlation or Pearson correlation analysis was performed to analyze the relation between SUVmax and maximum diameter.Binary logistic regression analysis was performed to identify the predictive factors for FOP.Finally,the receiver operating characteristic(ROC)curve analysis was used for evaluation of diagnostic efficiency.Results The SUVmax of FOP was lower than that of lung adenocarcinoma(3.1(1.7,4.9)vs 6.5(3.8,9.3);z=-4.598,P<0.01),and the maximum diameter of FOP was smaller than that of lung adenocarcinoma((18.0±6.3)mm vs(21.8±4.3)mm;t′=-3.424,P<0.01).The SUVmax was positively correlated with the maximum diameter in FOP group(rs=0.509,P<0.01),while the SUVmax of lung adenocarcinoma was not correlated with the lesion size(r=0.076,P>0.05).HRCT of the PET/CT system showed the fusiform shape were more common in FOP(χ^2=9.549,P<0.05).Multivariate regression analysis identified that SUVmax≤7.1,diameter≤18.3 mm,and fusiform shape were independent factors to predict FOP,with odds ratio(OR)of 10.585,4.674,9.073,respectively(all P<0.05).ROC curve analysis showed that the area under the curve(AUC)of SUVmax≤7.1 combined with diameter≤18.3 mm and fusiform nodule was 0.860,and the sensitivity,specificity,positive predictive value,negative predictive value and accuracy were 97.8%(44/45),70.2%(33/47),75.9%(44/58),97.1%(33/34),and 83.7%(77/92),respectively.Conclusion SUVmax≤7.1 combined with maximum diameter≤18.3 mm and fusiform shape may predict solid nodular FOP.