MRI Characteristics of Pediatric Renal Tumors: A SIOP-RTSG Radiology Panel Delphi
Study
van, der Beek Justine N. ✉; Watson, Tom A.; Nievelstein, Rutger A. J.; Brisse, Herve J.; Morosi, Carlo; Lederman, Henrique M.; Coma, Ana; Gavra, Maria M.; von, Steyern Kristina Vult; Lakatos, Karoly; Breysem, Luc; Varga, Edit [Varga, Edit (Gyermekgyógyászat...), szerző] II. Sz. Gyermekgyógyászati
Klinika (SE / AOK / K); Le, Pointe Hubert Ducou; Lequin, Maarten H.; Schaefer, Jurgen F.; Mentzel, Hans-Joachim; Hotker, Andreas M.; Calareso, Giuseppina; Swinson, Sophie; Kyncl, Martin; Granata, Claudio; Aertsen, Michael; Di, Paolo Pier Luigi; de, Krijger Ronald R.; Graf, Norbert; Olsen, Oystein E.; Schenk, Jens-Peter; Van, den Heuvel-Eibrink Marry M.; Littooij, Annemieke S.
Background The SIOP-Renal Tumor Study Group (RTSG) does not advocate invasive procedures
to determine histology before the start of therapy. This may induce misdiagnosis-based
treatment initiation, but only for a relatively small percentage of approximately
10% of non-Wilms tumors (non-WTs). MRI could be useful for reducing misdiagnosis,
but there is no global consensus on differentiating characteristics. Purpose To identify
MRI characteristics that may be used for discrimination of newly diagnosed pediatric
renal tumors. Study Type Consensus process using a Delphi method. Population Not applicable.
Field Strength/Sequence Abdominal MRI including T1- and T2-weighted imaging, contrast-enhanced
MRI, and diffusion-weighted imaging at 1.5 or 3 T. Assessment Twenty-three radiologists
from the SIOP-RTSG radiology panel with >= 5 years of experience in MRI of pediatric
renal tumors and/or who had assessed >= 50 MRI scans of pediatric renal tumors in
the past 5 years identified potentially discriminatory characteristics in the first
questionnaire. These characteristics were scored in the subsequent second round, consisting
of 5-point Likert scales, ranking- and multiple choice questions. Statistical Tests
The cut-off value for consensus and agreement among the majority was >= 75% and >=
60%, respectively, with a median of >= 4 on the Likert scale. Results Consensus on
specific characteristics mainly concerned the discrimination between WTs and non-WTs,
and WTs and nephrogenic rest(s) (NR)/nephroblastomatosis. The presence of bilateral
lesions (75.0%) and NR/nephroblastomatosis (65.0%) were MRI characteristics indicated
as specific for the diagnosis of a WT, and 91.3% of the participants agreed that MRI
is useful to distinguish NR/nephroblastomatosis from WT. Furthermore, all participants
agreed that age influenced their prediction in the discrimination of pediatric renal
tumors. Data Conclusion Although the discrimination of pediatric renal tumors based
on MRI remains challenging, this study identified some specific characteristics for
tumor subtypes, based on the shared opinion of experts. These results may guide future
validation studies and innovative efforts. Technical Efficacy Stage: 3
