Neuroblastoma : Imaging Studies

Imaging studies play an important role in the evaluation of a patient with neuroblastoma. Plain radiographs may show a calcified abdominal or a posterior mediastinal mass. The primary tumor can be evaluated by CT scan or MRI scan with contrast. MRI is superior to CT scan in detecting intraspinal extension of the tumor and demonstrating relationship between the tumor and major vessels. If imaging studies show intratumoral calcification and/or encasement of major vessels by the tumor, it strongly favors the diagnosis of neuroblastoma over Wilms tumor. Metaiodobenzylguanidine scan (mIBG scan) is useful for staging. 131I-mIBG is taken up by adrenergic secretory vesicles of tumor cells in both primary and metastatic sites. mIBG scan is also used to detect tumor relapse after initial therapy. The image shows an abdominal CT scan from an 18 month old male who presented with abdominal distension. This axial post contrast view demonstrates a large retroperitoneal mass encasing the aorta and lifting it forwards. The left kidney is displaced laterally. These features are typical of a large neuroblastoma which classically envelop and displace large vessels - a feature not seen with Wilms tumor. Case courtesy of Dr Frank Gaillard, Radiopaedia.org. From the case Neuroblastoma