Li Meng, Wu Ning, Liang Ying, Zheng Rong, Liu Ying, Zhang Wen-jie, Zhao Ping
Peking Union Medical College, Beijing 100021, China.
Zhonghua Zhong Liu Za Zhi. 2009 Apr;31(4):288-92.
To evaluate the diagnostic value of PET-CT with (18)F-FDG in preoperative N staging of non-small cell lung cancer (NSCLC), especially the additional value of CT attenuation and the dual-time-point imaging in determining the lymph nodes status.
Forty-three NSCLC patients underwent curative surgical resection after integrated (18)F-FDG PET-CT examination. The initial scan images were analyzed by two methods. In the first method, the nodal status was determined by (18)F-FDG uptake only (method PET). In the second method, the nodal status was determined by uptake associated with CT attenuation (method PET and CT attenuation). Nodal uptake was interpreted visually and semi quantitatively. For dual-time-point imaging, a retention index (RI) > 10% was regarded as increasing trend. Histopathologic results served as the reference standard.
On the per-nodal-station (group) basis, the diagnostic sensitivity, specificity, accuracy, PPV, and NPV were 88.0%, 88.4%, 88.3%, 59.5% and 97.4%, respectively, by the method 1; 84.0%, 94.6%, 92.9%, 75.0% and 96.8%, respectively, by the method 2. The specificity and accuracy between these two methods had statistically significant difference (P < 0.05). Twenty-eight nodal groups underwent dual-time-point imaging and the differences of DeltaSUV(max) and RI between benign and malignant groups had no statistically significant difference (P > 0.05). Eleven groups were malignant in 23 lymph nodal groups which had an increasing trend. Among the 5 nodal groups which did not show increase in delayed scan, one group was malignant.
(18)F-FDG PET-CT has high diagnostic value in the preoperative N staging of NSCLC, and combining uptake with CT attenuation of lymph nodes can improve the specificity and accuracy. For the lymph nodes with high uptake in the initial scan, increasing uptake in delayed scan has little effect in differential diagnosis, but no increasing in delayed phase is more prone to benign diagnosis.
评估¹⁸F-FDG PET-CT在非小细胞肺癌（NSCLC）术前N分期中的诊断价值，尤其是CT衰减及双时相成像在判断淋巴结状态方面的附加价值。
43例NSCLC患者在接受¹⁸F-FDG PET-CT综合检查后行根治性手术切除。对初始扫描图像采用两种方法进行分析。第一种方法，仅通过¹⁸F-FDG摄取来确定淋巴结状态（PET法）。第二种方法，通过摄取情况结合CT衰减来确定淋巴结状态（PET与CT衰减法）。淋巴结摄取情况采用视觉和半定量分析。对于双时相成像，滞留指数（RI）>10%被视为有上升趋势。组织病理学结果作为参考标准。
在每个淋巴结站（组）的基础上，方法1的诊断敏感性、特异性、准确性、阳性预测值和阴性预测值分别为88.0%、88.4%、88.3%、59.5%和97.4%；方法2分别为84.0%、94.6%、92.9%、75.0%和96.8%。这两种方法之间的特异性和准确性有统计学显著差异（P<0.05）。28个淋巴结组进行了双时相成像，良性和恶性组之间的ΔSUV(max)和RI差异无统计学显著差异（P>0.05）。在23个有上升趋势的淋巴结组中，11组为恶性。在延迟扫描未显示上升的5个淋巴结组中，1组为恶性。
¹⁸F-FDG PET-CT在NSCLC术前N分期中具有较高的诊断价值，将淋巴结摄取情况与CT衰减相结合可提高特异性和准确性。对于初始扫描中摄取高的淋巴结，延迟扫描中摄取增加在鉴别诊断中作用不大，但延迟期无增加更倾向于良性诊断。
