18F-FDGPET／CT在鉴别尘肺病大阴影良恶性的应用价值

Clinical value of 18F-FDG PET/CT in differentiation between benign lesions and lung cancer for large shadows in patients with pneumoconiosis

【摘要】目的探讨18F-FDGPET／CT在鉴别尘肺病大阴影良恶性的临床应用价值。方法回顾性分析确诊的21例尘肺患者的肺内37个大阴影，所有患者均进行18F-FDGPET／CT全身显像并计算高摄取病灶的最大标准摄取值（SUVmax）；12个病灶经CT引导肺穿刺活检病理诊断、1例经纤维支气管镜、肺泡灌洗液病理诊断及痰均未见肿瘤细胞，其余随访两年以上证实；经t检验分析高摄取尘肺结节与肺癌之间的差异。结果13例尘肺患者PET／CT显像共发现17个高18F-FDG摄取的肺内团块或结节，其中5个病例的5个病灶确诊为非小细胞肺癌（其中鳞癌1例，腺癌3例，1例为鳞癌术后复发），7个病例的7个病灶穿刺活检病理提示为慢性炎性增生；1例患者经纤维支气管镜检查未见肿瘤细胞，后随访2．5年，病灶无明显变化。8例患者的20个肺内结节无18F-FDG异常代谢增高，经随访证实为良性结节。肺癌病灶的直径范围为1．6--6．8cm，SUVmax范围为4．8～14．0；高18F-FDG摄取的尘肺结节病灶直径范围为1．5—4．6cm，SUVmax范围为2．6～12．4；两者的直径及最大标准摄取值的差异均无统计学意义（P〉0．05）。18F-FDGPET／CT诊断肺癌的特异性为62．5％（20／32），准确性为67．6％（25／37），假阳性率为37．5％（12／32），阴性结果预测值为100％（20／20）。21例尘肺患者肺癌的检出率为23．8％（5／21）。结论 18F-FDGPET／CT显像中如果尘肺患者肺内病灶无18F-FDG摄取或为对称性且都呈高18F-FDG摄取，提示为良性尘肺结节；而对于尘肺患者肺内单发病灶18F-FDGPET／CT的价值有待进一步研究。

Objective To evaluate the clinical value of 18F-FDG PET/CT in the differentiation between benign lesions and lung cancer for large shadows in patients with pneumoconiosis. Methods A retrospective study was conducted in 21 patients with a confirmed diagnosis of pneumoconiosis who had a total of 37 large shadows in the lung fields as shown by whole-body ISF-FDG PET/CT imaging, and ISF-FDG uptake was evaluated using the maximum standardized uptake value （SUV~）. Twelve lesions were examined by CT-guided aspiration biopsy, and one case underwent fiberoptic bronehoscopy, as well as tests based on bronchoalveolar lavage fluid and sputum; the other cases were followed up for more than 2 years. The differences between pneumoconiosis nodules with high ISF-FDG uptake and lung cancer were evaluated by t test. Results Seventeen lung masses or nodules with high lSF-FDG uptake were detected in 13 patients; among the 13 patients, 5 lesions of 5 cases were confirmed as non-small cell lung cancer （ 1 case of squamous cell carcinoma, 3 cases of adenocarcinoma, and 1 case of recurrent squamous cell carcinoma after operation）, and 7 lesions of 7 cases were progressive massive fibrosis as shown by CT-guided aspiration biopsy; one case had no tumor cells detected by fiberoptie bronchoscopy, and 2.5-year follow-up revealed no changes in the lesions. The other 8 patients showed no increased 18F-FDG uptake in their 20 lung nodules, which were confirmed as benign lesions by follow-up. The diameter range of lung cancer was 1.6--6.8 cm, and the SUVmax range was 4.8 --14.0; the diameter range of pneumoconiosis nodules with high 18F-FDG uptake was 1.5--4.6 cm, and the SUVmax range was 2.6 --12.4. There were no significant differences in diameter and SUVmax between the lung cancer and pneumoconiosis nodules with high 18F-FDG uptake （P〉0.05 for both）, lSF-FDG PET/CT had a specificity of 62.5% （20/32）, an accuracy of 67.6% （25/37）, a false-positive rate of 37.5% （12/32）, and a negative predictive value of 100% （20/20） for the diagnosis of lung cancer. The lung cancer detection rate was 23.8% （5/21）. Conclusion In 18F-FDG PET/CT imaging for patients with pneumoconiosis, the lung lesions without 18F-FDG uptake or symmetrical lesions with high 18F-FDG uptake are considered as benign pneumoconiosis nodules; however, 18F- FDG PET/CT might have a limited role in evaluating the solitary lung lesions in patients with pneumoconiosis and needs further study.