Objectives To investigate the correlation between maximum standardized uptake value (SUV max)of 18FDG PET-CT and iodine-related attenuation (IRA) of dual energy CT (DECT) of primary tumours and 18FDG PET-CT positive thoracic lymph nodes (LN) in patients with lung cancer. Methods 37 patients with lung cancer (27 NSCLC, 10 SCLC, 86 18FDG PET-CT positive thoracic LN) who underwent both 18FDG PET-CT and DECT were analyzed. The mean study interval between 18FDG PET-CT and DECT was ≤21 days in 17 patients. The mean and maximum IRA of DECT as well as of virtual unenhanced and virtual 120 kV images of DECT was analyzed and correlated to the SUV max of 18FDG PET-CT in all tumours and 18FDG PET-CT positive thoracic lymph nodes. Further subgroup analysis was performed for histological subtypes in all groups. Results A moderate correlation was found between SUV maxand maximum IRA in all tumours (n=37;r=0.507;p=0.025) whereas only weak or no correlation were found between SUV max and all other DECT measurements. A strong correlation was found in patients with study intervals <21 days (n=17; r=0.768;p=0.017). Analysis of histological subtypes of lung cancer showed a strong correlation between SUV maxand maximum IRA in the analysis of all patients with NSCLC (r=0.785y=0.001) and in patients with NSCLC and study intervals ≤21 days (r=0.876;p=0.024). Thoracic LN showed moderate correlation between SUV maxand maximum IRA in patients with study intervals ≤21 days (r=0.654; p=0.010) whereas a weak correlation was found between SUV max and maximum IRA in patients with study intervals >21 days (r=0.299; p=0.035). Conclusions DECT could serve as a valuable functional imaging test for patients with NSCLC as the IRA of DECT correlates with SUVmax of 18FDG PET-CT.
- 18FDG PET-CT
- Dual energy computed tomography
- Lung cancer
- Tumor vascularity
- Tumour staging
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging