Staging of non-small-cell lung cancer with FDG-PET/CT: Is there a correlation of morphologic tumor characteristics and metabolic activity?
Aim:

FDG-PET/CT is widely accepted for staging of non-small-cell lung cancers [NSCLC]. The aim was to determine morphological data as well as the metabolic activity in patients with NSCLC. These data were correlated with TNM stage and histology to test for possible predictive values.

Methods and Materials:

This retrospective study examined lung cancer patients which received a whole-body PET/CT for tumor staging. The maximal and mean size and the maximal and mean density in Hounsfield units [HU] of the primary tumor were measured in CT. Metabolic activity was measured as standardized uptake value [SUVmax]. The individual tumor stage (clinical and postoperatively) as well as histology and grading were determined. Univariate analysis was performed between all tumor parameter.

Results:

202 patients were included in our study. Mean tumor size was 49 ±22 mm, the mean tumor density was measured with 53 ± 66 HU. The SUVmax ranged from 0.4 to 42. In 123 cases histological grading and in 144 patients complete TNM staging was documented with c or p N-stage. Tumor size (r = -0.13) as well as density (r = -0.095) and metabolic activity (r = -0.077) showed no relevant correlation. There was no correlation between tumor grading and size (r = -0.15), volume (r = -0.097), and metabolic activity (r = -0.085). Multivariate analysis will be added.

Conclusion:

There was no significant correlation between the different metabolic and morphologic tumor parameter from PET/CT and clinical data of patients with NSCLC. Up to now we could not identify a combination of imaging data from PET/CT with a predictive capability for tumor staging.