A rare case of pediatric primary central nervous system differentiating neuroblastoma: an unusual and rare intracranial primitive neuroectodermal tumor (a case report)

Abstract

Neuroblastoma represents the most common solid extracranial tumor in children under 5, accounting for 8% to 10% of all childhood cancers. Primary central nervous system (CNS) neuroblastomas are a very rare location and only few cases are available in the literature. It was first described in 1973 by Hart and Earl as supratentorial primitive neuroectodermal tumors. Clinical presentation is highly variable and depends on the initial location of the tumor. Regarding imaging, primary brain neuroblastoma shows no pathognomonic appearance on brain computed tomography (CT) whether or not enhanced or magnetic resonance imaging (MRI). There were no standard guidelines available for the adjuvant treatment in case of primary CNS neuroblastoma. Surgery remains the main and the first tool toward these lesions. Radiotherapy associated or not to chemotherapy is offered based on patient´s age. Here, the authors report a new pediatric case of primitive central nervous system neuroblastoma revealed by an intracranial hypertension syndrome and confirmed by both histopathological and immunohistochemistry study after a gross total surgical excision. The postoperative course was uneventful and the child had good recovery.

Keywords: Neuroblastoma; case report; chemotherapy; radiotherapy; surgery.

Figure 1

axial non-enhanced brain CT scan showing a left basifrontal tumor measuring 50 x 45 mm in diameter reaching the ipsilateral temporal lobe; this mass had a triple fleshy component (blue arrow), cystic (red arrows) and scattered foci of calcification (yellow arrows) in variable proportions; note the midline shift estimated at 6 mm without any uncal herniation

Figure 2

A) brain MRI in axial section showing a left basifrontal intra-axial lesion extended to the left polar temporal region, in hypointense on the T1-weighted sequences; B) in heterogeneous isosignal on the T2 sequences; C) not surrounded by an edematous reaction on FLAIR (fluid attenuated inversion recovery) sequence; D) enhancement after gadolinium injection is heterogeneous; E) note the heterogeneous hyper signal on the diffusion weighted images (DWI) without any hyperperfusion on perfusion sequences; F) cystic plaques and hypointense spots are seen on the gradient echo sequence; there was no intra-tumor bleeding on the susceptibility sequences

Figure 3

a thoraco-abdomino-pelvic CT scan in several coronal sections showing the absence of a primary lesion or any unusual enhancing mass

Figure 4

planar whole-body skeletal scan in anterior and posterior projections showing the absence of unusual increased 99mTc-MDP uptake in the whole skeleton; A) anterior and posterior blood pool whole body views; B) delayed anterior and posterior whole body bone scan

Figure 5

axial non-enhanced postoperative CT scan showing a porencephalic cavity at the level of the tumor bed associated with pneumocephalus even subcutaneously; note the disappearance of midline shift and good decompression of healthy parenchyma

Figure 6

A) microscopic histopathological images showing a focal necrosis tumor proliferation, vaguely lobulated and crossed by fibrous septa (H & E 400x); this proliferation is of moderate cellularity made up essentially of small round monomorphic basophilic cells with a rounded or oval nucleus with a high nuclear/cytoplasmic ratio; focally, there was a transition between these undifferentiated embryonic cells with other neurocytically differentiated cells; the background of the proliferation is clearly fibrillary with presence of numerous Homer-Wright rosette images and pseudo-rosettes (H & E 400x); it is associated with micro calcifications and rare spumous histiocytes; B) microscopic immunohistochemistry (IHC) study showing that tumor cells were positive for INI-1, neurospecific enolase (NSE) (IHC for NSE 400x); C) synaptophysin (IHC for synaptophysin 400x)