Prenatal sonographic and magnetic resonance imaging diagnosis of cystic neuroblastoma.

Abstract

Neuroblastoma is the most frequent extracranial solid tumor in childhood, but it is seldom diagnosed prenatally. These tumors may arise from any site of the sympathetic nervous system in fetuses. With the increasing use of prenatal ultrasound to detect fetal anomalies, the possibility of early detection of children with neuroblastoma is increasing1. We report such a case and present magnetic resonance imaging (MRI) findings. A 20-year-old primigravida first presented at 26 weeks of gestation for routine examination. Transvaginal ultrasound examination showed a simple cystic intra-abdominal mass measuring 16 × 19 mm in diameter. The possibility of neuroblastoma was raised. A follow-up sonographic examination performed at 29 gestational weeks showed an increase in size of the mass (to 43 × 44 mm) with intracystic septations, suggesting intracystic hemorrhage (Figure 1). MRI performed at 33 weeks revealed a complex mass which was located between the right kidney and liver. For the fetal MRI, an ultrafast imaging sequence, Half-Fourier acquisition single shot turbo spin echo (HASTE) was employed. In T2-weighted MRI scans, the lesion appeared as a well-defined, predominantly cystic complex mass measuring 55 × 46 mm (Figure 2). Three weeks after the MRI scan, the woman went into spontaneous labor and delivered a male infant weighing 2770 g. Postnatal examination confirmed the presence of an adrenal tumor. A laparotomy was performed on the third day postpartum. The tumor was resected. Histopathological analysis revealed a mildly differentiated neuroblastoma with extensive areas of hemorrhage and necrosis. The infant had an uncomplicated postoperative course and was discharged 9 days later. He required no further treatment, and remained free of disease 8 months later. Transverse fetal abdominal sonogram at 29 weeks showing the tumor with intracystic septations. Magnetic resonance image at 33 weeks. Half-Fourier acquisition single shot turbo spin echo (HASTE), T2-weighted image: a well demarcated, predominantly cystic fetal abdominal mass, showing different areas with low-signal intensity suggesting intratumoral hemorrhage. Our case provides an ultrasound and MRI demonstration of a cystic neuroblastoma. Because of its better demonstration of morphological details, MRI is likely to provide a better differential diagnosis of neuroblastoma from conditions such as adrenal hemorrhage, subdiaphragmatic sequestration or renal cortical cysts2, 3. MRI is likely to become an important adjunct to ultrasound, especially in cases in which ultrasound findings are unclear due to maternal obesity or oligohydramnios4. It provides significant additional information that improves diagnostic accuracy in evaluation of the fetal brain, spine, neck, chest, abdomen and urinary tract. In the future, it is very likely that real-time MRI will become clinically available which would further improve the technique5. H. Aslan*, B. Ozseker , A. Gul*, * Department of Perinatology, SSK Bakirkoy Maternity Children's Hospital, Istanbul, Turkey, Department of Radiology, Kadikoy Acibadem Hospital, Istanbul, Turkey