Esthesioneuroblastomas: Reservations and Recommendations

Abstract

Neuroectodermal tumour has a wide range of biological activity that ranges from an indolent course to local recurrence and rapid widespread metastasis. We describe, herewith, 2 patients with Esthesioneuroblastomas (ENB) who had varied atypical clinical presentation. The first case presented with Intracranial Pressure (ICP) headache and acute visual deterioration with radiology revealing an extra axial lesion with extension into the nasal cavity while the second case presented with nasal congestion and progressive headache of long duration. We review the unusual characteristics that may uncommonly occur in ENBs and elaborate regarding which of these must be considered when evaluating patients with this malignancy.

Keywords: Intracranial tumours; Nasal tumours; Olfactory neuroblastoma.

[Table/Fig-1]:

Preoperative imaging (Case 1) Plain CT brain, axial and coronal: (a,b) showing a 4.2x5.4x5.5cm mass with few cystic areas noted mainly in the left basifrontal region with perilesional oedema and extending into the left nasal cavity, sphenoid and ethmoid sinuses. MRI Brain (preoperative) showing a left basifrontal and midline, extra-axial lesion, axial section, hypo on T1W; (c) hyperintense on T2W; (d) with perilesional oedema on FLAIR, coronal section (e). The lesion had heterogenous enhancement on contrast; (f,g,h – axial, coronal, sagittal) with diffusion restriction; (i) The lesion seemed to arise from the left nasal cavity with invasion into the ethmoid and sphenoid sinus with destruction of the cribriform plate, as seen on the sagittal section of the MRI; (h) The imaging features suggested a possibility of Esthesioneuroblastoma; (j) shows the postop CT scan, axial section, with gross total excision of the tumour with significant residual oedema.

[Table/Fig-2]:

Intraoperative images: (a) Bifrontal craniotomy and excision of tumour, seen after cutting the falx and superior saggital sinus anteriorly and retracting the frontal lobe. Frontal sinus has been exteriorized; (b) Showing the anterior cranial fossa floor post gross total excision with; (c) exteriorization of the frontal sinus and denuding the mucosa and obliterating the sinus with bone wax.

[Table/Fig-3]:

Post op and preop CT of (Case1) showing the preop axial CT in the upper section (a,b), with a hypo to isodense lesion with perilesional oedema and the lower two sections (cd) showing postop changes and gross total excision of the tumour.

[Table/Fig-4]:

Preoperative MRI Scan of the brain, post transnasal excision of the nasal tumour (Case 2) showing a small well defined lobulated extra-axial lesion (hyperintense on T1: (a) hyperintense on FLAIR; (b) and intense post contrast enhancement; (c) axial sections measuring ~ 1.7 x 1.5 x 2.6cm is seen with a broad base to the dura in the right subfrontal region abutting the right gyrus rectus superiorly and floor of anterior cranial fossa inferiorly. Cortical discontinuity with evidence of bony destruction of the right cribriform plate was noted. The contrast series shows intense enhancement on coronal; (d) and sagittal; (e) sections which show and involvement of the right half of the anterior cranial fossa floor with posterior extension into the sella.

[Table/Fig-5]:

Postoperative Plain CT scan of the brain (Case 2) {Axial, (a,b) contrast sagittal (b) and contrast coronal (c)} sections showing total excision of the tumour, the inner table of the frontal sinus has been removed for exteriorization of the sinus and anterior cranial fossa carpeting as seen on section b and c.

[Table/Fig-6]:

H&E Section shows nests and sheets of uniform cells with scant to moderate cytoplasm, round nuclei with stippled chromatin, indistinct nucleoli, mild nuclear pleomorphism, surrounded by delicate stroma with congested capillaries 100x; Left upper inset showing same section magnified - 200x.

[Table/Fig-7]:

IHC stained tumour cells showing strong cytoplasmic positivity for synaptophysin (100x) Left upper inset showing the IHC stained sustentacular cells showing cytoplasmic positivity for S-100 protein (100x) and right upper inset (200x).