Implications of false negative and false positive diagnosis in lymph node staging of NSCLC by means of ¹⁸F-FDG PET/CT

PLoS One. 2013 Oct 25;8(10):e78552. doi: 10.1371/journal.pone.0078552. eCollection 2013.


Background: Integrated ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) is widely performed in hilar and mediastinal lymph node (HMLN) staging of non-small cell lung cancer (NSCLC). However, the diagnostic efficiency of PET/CT remains controversial. This retrospective study is to evaluate the accuracy of PET/CT and the characteristics of false negatives and false positives to improve specificity and sensitivity.

Methods: 219 NSCLC patients with systematic lymph node dissection or sampling underwent preoperative PET/CT scan. Nodal uptake with a maximum standardized uptake value (SUV(max)) >2.5 was interpreted as PET/CT positive. The results of PET/CT were compared with the histopathological findings. The receiver operating characteristic (ROC) curve was generated to determine the diagnostic efficiency of PET/CT. Univariate and multivariate analysis were conducted to detect risk factors of false negatives and false positives.

Results: The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT in detecting HMLN metastases were 74.2% (49/66), 73.2% (112/153), 54.4% (49/90), 86.8% (112/129), and 73.5% (161/219). The ROC curve had an area under curve (AUC) of 0.791 (95% CI 0.723-0.860). The incidence of false negative HMLN metastases was 13.2% (17 of 129 patients). Factors that are significantly associated with false negatives are: concurrent lung disease or diabetes (p<0.001), non-adenocarcinoma (p<0.001), and SUV(max) of primary tumor >4.0 (p=0.009). Postoperatively, 45.5% (41/90) patients were confirmed as false positive cases. The univariate analysis indicated age > 65 years old (p=0.009), well differentiation (p=0.002), and SUV(max) of primary tumor ≦4.0 (p=0.007) as risk factors for false positive uptake.

Conclusion: The SUV(max) of HMLN is a predictor of malignancy. Lymph node staging using PET/CT is far from equal to pathological staging account of some risk factors. This study may provide some aids to pre-therapy evaluation and decision-making.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Non-Small-Cell Lung / diagnostic imaging
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • False Negative Reactions
  • False Positive Reactions
  • Female
  • Fluorodeoxyglucose F18*
  • Humans
  • Lung Neoplasms / diagnostic imaging
  • Lung Neoplasms / pathology*
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Multimodal Imaging*
  • Neoplasm Staging
  • Positron-Emission Tomography*
  • Retrospective Studies
  • Risk Factors
  • Tomography, X-Ray Computed*


  • Fluorodeoxyglucose F18

Grants and funding

This work was supported partially by Beijing Natural Science Foundation (Grant Nos 11G2633), the National High Technology Research and Development Program of China (863 Program, No. 2012AA02A502), and Beijing Municipal Science & Technology Commission (No. Z111107067311018). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.