Comparison of Whole-Body MRI and Whole-Body PET-CT for Staging of Advanced Bronchial Carcinoma

C. Plathow, S. Eschmann, P. Aschoff, V. Heinrich, J. Schaefer, C. Claussen, T. Hehr, C. Pfannenberg, H.-P. Schlemmer
Eberhard-Karls-University Tuebingen, Tuebingen, Germany
 |  24-05-2007

Purpose

To compare whole-body MRI with whole-body PET-CT and thereby correctly evaluate tumor staging in patients with advanced Non-Small-Cell Lung Carcinoma (NSCLC).


Materials and methods

16 patients (11 male / 5 female) ranging in age from 49 to 71 years (mean age 62 years) with stage IIIb to IV NSCLC were examined prior to chemotherapy using whole-body MRI adapted for oncologic staging (Siemens Medical Solutions, MAGNETOM Avanto, 5 subsequent table positions, FLAIR axial (Brain), STIR coronal (whole-body) and axial (Neck),
T2- weighted STIR-TSE axial (thorax), T1-weighted SE axial and coronal pre and post contrast (brain), T1-weighted 3D VIBE axial pre and post contrast (thorax), T2-weighted TSE fatsat axial (abdomen), T1-weighted 2D FLASH fatsat axial pre and post contrast (abdomen, neck, pelvis), T2-weighted STIR-TSE axial (pelvis); total acquisition time 60 min). Within a period of 3 days, whole-body PET-CT was performed (400 MBq F-18-FDG, native CT in low dose technique and after CM application, iterative image reconstruction with CT based attenuation correction, total acquisition time 60 min). This was repeated after 3 weeks for first control. Tumors were staged independently by experienced radiologists and nuclear medicine specialists. In cases of discrepancy of tumor staging between whole-body MRI and PET-CT, the follow- up
PET-CT served as a control.


Results

In 14 out of 16 patients, T-staging was identical using whole-body MRI and whole-body PET-CT. In 2 patients, MRI was able to correctly differentiate between tumor infiltration and no tumor infiltration of the chest wall, which was confirmed by the follow-up. In these 2 cases only STIR and T1-weighted 3D VIBE post contrast application sequences were able to correctly perform T-stage, whereas PET-CT over- or underestimated T-staging. In 13 out of 16 patients N-staging was identical; in 1 patient whole-body MRI was able to correctly define a hilar lymphatic node, whilst in 2 cases PET-CT was able to correctly define ipsi- and contralateral lymphatic nodes. In all patients M-staging was identical.