Guenther Karl Schneider MD, PhD, Presenter: Research Grant, Siemens AG Speakers Bureau, Siemens AG Speakers Bureau, Bracco Group Speakers Bureau, Bayer AG Research Grant, Bracco Group Speakers Bureau, Guerbet SA

Stefan Radiologie Uniklinik Rick, Abstract Co-Author: Nothing to Disclose

Jonas Stroeder MD, Abstract Co-Author: Nothing to Disclose

Arno Buecker MD, Abstract Co-Author: Consultant, Covidien AG Speaker, Covidien AG Co-founder, Aachen Resonance GmbH Research Grant, Siemens AG

Peter Fries MD, Abstract Co-Author: Nothing to Disclose

In 53 pediatric pts. with suspected malignant tumors whole body MRI was performed and evaluated as the sole staging procedure including evaluation of the lungs in comparison to established staging procedures as FDG-PET, MIBG or bone scintigraphy, CT and ultrasound. Furthermore, findings in follow-up whole body MRI were used for evaluation of tumor response and tumor recurrence, again compared against other established imaging methods.

209 whole body examinations in 53 pts. were performed for staging and follow-up of benign and malignant tumors confirmed by histology and/or surgical exploration. In 10 pts. benign tumors were diagnosed. In the remaining 43 pts 14 lymphoma and 29 solid tumors including neuro-, nephro- and hepatoblastoma as well as different types of sarcoma were found. MR protocol incl. T1w dynamic CE GRE sequences of the abdomen post CM injection (0,05 mmol/kg BW Gd-BOPTA (MultiHance)) and during the liver specific phase. DWI was acquired during free breathing and transversal T2w TSE sequences with navigator triggering and a composed whole-body STIR-sequence in coronal orientation were acquired. Comparison of whole body MRI was performed directly with the different available imaging methods and regarding the cumulative findings from all other imaging procedures together.

MRI correctly differentiated malignant and benign tumors in 52 out of 53 pts. Differences between MRI and CT were seen regarding the number of detected small lung metastases (< 3mm), however relevant lesions for staging were correctly diagnosed. In a case of lung metastases with concomitant pneumonia MRI with DWI was able to identify a central metastases, which could not be differentiated from surrounding pneumonia and atelectasis on CT. Recurrent tumors and restaging was correctly facilitated by MRI, sensitivity for detection of small abdominal mets (< 10 mm) was better for MRI as compared with PET imaging.

Whole body imaging studies performed with the described technique can correctly stage and diagnose a variety of malignant tumors in pediatric patients and further large scale studies have to prove whether MRI can replace at least some of the actually established staging procedures.

Inferior accuracy of whole body STIR MRI was recently published, this study demonstrates the potential of whole body MRI using more advanced techniques for evaluation of pediatric malignancies.

Schneider, G, Rick, S, Stroeder, J, Buecker, A, Fries, P, Whole Body MRI including Diffusion-weighted and Conventional Unenhanced and Contrast Enhanced Imaging as the Sole Staging and Follow-up Imaging Procedure in Pediatric Tumors - Comparison with Established Imaging Modalities.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14014654.html