Prospective assessment of MRI for imaging retroperitoneal metastases from testicular germ cell tumours
Received 30 July 2008; received in revised form 6 October 2008; accepted 26 October 2008.
Aim
To determine the sensitivity of magnetic resonance imaging (MRI) in the detection of retroperitoneal lymph nodes in patients with testicular germ cell tumours (TGCT).
Methods and materials
A prospective study of 52 patients (mean age 34 years, range 18–54 years) was performed. Imaging of the retroperitoneum was performed using multidetector computed tomography (CT) and 1.5T MRI systems. The CT and MRI images were read independently by three observers. The number, size, and site of enlarged nodes (≥10mm maximum short axis diameter) were recorded. Retroperitoneal nodal detection on MRI was compared to CT.
Results
Twenty-two (42%) of the 52 patients had no retroperitoneal disease; in remaining 30 patients 51 enlarged nodes were identified. On a per patient basis readers 1, 2, and 3 identified nodal disease in 28 of 29, 29 of 30, and 24 of 30 patients, respectively, using MRI compared to CT. Thus for experienced radiologists (readers 1 and 2) MRI is comparable to CT for nodal detection (i.e., this study excludes MRI being inferior to CT with 80% power and 5% type 1 error).
Conclusion
MRI offers an alternative method for staging the retroperitoneum in young patients being followed for TGCT and has the major advantage of avoiding exposure to ionizing radiation.
aDepartment of Radiology, Institute of Cancer Research & Royal Marsden Hospital, Sutton, Surrey, UK
bDepartment of Computing and Statistics, Royal Marsden Hospital, Institute of Cancer Research & Royal Marsden Hospital, Sutton, Surrey, UK
cDepartment of Academic Urology Unit, Institute of Cancer Research & Royal Marsden Hospital, Sutton, Surrey, UK
Guarantor and correspondent: S.A. Sohaib, Department of Imaging, Royal Marsden Hospital, Downs Road, Sutton, Surrey, SM2 5PT, UK. Tel.: +44 20 8661 3213/4/5; fax: +44 20 8661 3506.
ABSTRACT