肺硬化性肺泡细胞瘤的18F-FDG PET/CT显像特征

目的 探讨肺硬化性肺泡细胞瘤（PSP）的¹⁸F-FDGPET/CT显像特征。方法 回顾性分析16例经病理证实为PSP的患者的临床及PET/CT资料。观察病变的部位、形态、大小、病灶内部及边缘情况、代谢情况,测量病灶的最大标准化摄取值（SUV_max）。对其中6例接受¹⁸F-FDGPET/CT双时相显像的患者,计算平均滞留指数（RI）。比较早期与延迟期SUV_max的差异,并分析病灶直径与SUV_max的相关性。结果 16例患者共16个病灶,位于右肺7个,位于左肺9个。病灶均呈圆形或类圆形,直径（1.97±0.61）cm,密度均匀,无囊变及坏死,CT值（29.87±4.71）HU。5个病灶可见钙化。14个病灶边缘光滑,2个病灶边缘可见短毛刺。2个病灶可见边缘磨玻璃影,12个病灶存在"血管贴边征",3个病灶存在"空气新月征"。PSP病灶SUV_max值为 2.71±2.13。6例双时相显像患者早期（2.44±1.57）与延迟期SUV_max值（2.74±1.83）差异无统计学意义（t=2.09,P>0.05）,RI为（7.23±10.29）%。PSP病灶直径与SUV_max间无相关性（r=0.188,P>0.05）。结论 PSP的PET/CT多表现为孤立性肺结节,其放射性分布呈轻或中度增高,"血管贴边征"和"空气新月征"及周围磨玻璃影常提示PSP可能性。

18F-FDG PET/CT features of pulmonary sclerosing pneumocytoma

Objective To investigate the characteristics of ¹⁸F-FDG PET/CT imaging in pulmonary sclerosis pneumocytoma (PSP). Methods The clinical and PET/CT data of 16 patients with pathologically proved PSP were retrospectively analyzed. The location, shape, size, internal and external edge of the lesion, as well as the metabolism of the lesions were observed. The mean retention index (RI) was calculated in 6 patients with ¹⁸F-FDG PET/CT dual phase imaging. The difference of SUV_max between early and delayed phase were compared. And the correlation between the diameter of lesions and SUV_max were analyzed. Results There were 16 lesions in all 16 patients, including 7 cases located at right lung and 9 located at left lung. The lesions were round with the diameter of (1.97±0.61)cm. The uniform density were observed with the CT value of (29.87±4.71)HU. And there was no cystic degeneration and necrosis. Calcification was found in 5 lesions. The edge of 14 lesions was smooth, and the edge of another 2 lesions showed short spicular sign. Two lesions showed visible edges of ground glass opacity. There were 12 lesions with "vascular welt sign" and 3 lesions with "air crescent sign". The SUV_max value of PSP was 2.71±2.13. There was no significant difference between the early SUV_max (2.44±1.57) and delayed SUV_max (2.74±1.83) in patients with dual phase imaging (t=2.09,P>0.05). RI was (7.23±10.29)%. There was no correlation between PSH diameter and SUV_max (r=0.188, P>0.05). Conclusion Most of PSP showed solitary pulmonary nodules in PET/CT imaging. The radioactive distribution was mild and moderate increase. The "vascular welt sign", "air crescent sign" and the surrounding ground glass opacity are the references findings of PSP.