Edinburgh Imaging

MSc projects 1516 005

Integrated 18-FDG PET-CT in the age of endobronchial ultrasound-guided fine needle assay in diagnosis & nodal staging of non-small cell lung cancer: factors that predict 'positivity' & clinical outcome.

  • Background: Non-small cell lung cancer (NSCLC) is staged according to the Tumour Node, Metastasis (TNM) staging system, which relies on accurate lymph node (LN) staging to predict outcome and prognosis. Preoperative staging is performed with a combination of integrated positron emission tomography and computed tomography (PET-CT) and endobronchial ultrasound-guided fine-needle aspiration (EBUS-FNA). The aim of this study was to assess factors on PET-CT that could predict nodal positivity on EBUS-FNA sampling and their effects on clinical outcome. 
  • Methods: 177 patients who underwent PET-CT and EBUS-FNA were analysed for nodal disease status using maximum standardised uptake values (SUVmax) above mediastinal background as a marker for positivity. Correlation with EBUS-FNA histology for 354 nodes was carried out to determine the accuracy of PET-CT staging. Chi-squared test was used to evaluate the relationship between increasing SUVmax and likelihood of nodal positivity. 
  • Results: Overall sensitivity specificity positive predictive value (PPV) and negative predictive value (NPV) for PET-CT staging , were 0.86, 0.60, 0.56 and 0.88 respectively. Area under the curve (AUC) from Receiver Operatm Characteristics (ROC) analysis was 0.79 and optimum cut-off was SUVmax 3.9. Increasing SUVmax correlated with increasing chance of malignant nodal involvement. Survival analysis of patients where EBUS-FNA and PET-CT staging was concordant versus those where they were discordant showed no significant overall survival benefit (p=0.9]). 
  • Conclusion: As the SUV max increases, the likelihood of metastatic nodal involvement increases. Survival outcome of NSCLC patients is not improved even if EBUS-FNA downstages PET-CT nodal disease. 
Project type:
  • Data acquisition & analysis
Imaging keywords:
Application / disease keywords:
  • Non-small cell lung cancer (NSCLC)
  • Nodal disease, mediastinal
  • Fine needle aspiration
  • 15-16