Esthesioneuroblastoma

Introduction: Esthesioneuroblastoma (EBN) is a rare and malignant tumor of olfactory epithelium. Due to its infrequency, there are several controversies regarding its treatment, being the endoscopic approach a new option. Objective: describe a young male case of EBN, its challenging diagnosis and options of treatment. Case report: 21 year old man who presented with a two month history of difficulty breathing and hyposmia after undergoing nasal vein cauterization for recurrent epistaxis. Physical examination confirmed a mucosal mass obstructing his left nostril. Magnetic Resonance Imaging of the face demonstrated a mass within the nasal septum infiltrating the oropharynx, hard palate, cribriform plaque and orbital lamina of the ethmoid bone. Endovascular embolization was performed followed by transsphenoidal endoscopic surgical excision. Anatomopathological and immunohistochemistry analysis confirmed the diagnosis of EBN. Repeat MRI-face showed a residual lesion requiring open craniotomy in addition to radio-chemotherapy. Conclusion: EBN is an uncommon malignant tumour arising in the superior aspect of nasal cavity. There is no consensus regarding optimal treatment strategies. Endoscopic transsphenoidal resection is reserved to early stages only and its use on advanced disease has been poorly explored.


Dear Editor,
A 64-year-old male presented with nasal obstruction, anosmia, and a reduction in visual acuity over the last few months, together with weight loss and a two-year history of headache. Computed tomography (CT) of the brain ( Figure 1A) showed an expansile lesion with poorly defined borders, occupying the ethmoid cells, sphenoid sinuses, and the anterior cranial fossa, accompanied by edema of the frontal lobes. On magnetic resonance imaging (MRI) scans ( Figures 1B, 1C, and 1D), the lesion showed restricted diffusion and intense enhancement after contrast administration. A biopsy was performed, and analysis of the biopsy sample revealed hyperchromatic cells organized around a fibrillar stroma, forming rosettes, consistent with a diagnosis of olfactory neuroblastoma. The lesion was staged histologically as grade I in the Hyams grading system. There was no evidence of cervical involvement or distant metastases. The patient died 15 days after undergoing the examinations.
Olfactory neuroblastoma, also known as esthesioneuroblatoma, is a rare malignant neoplasm of neuroectodermal origin and accounts for 3-6% of all malignant tumors of the paranasal sinuses. It has a bimodal age distribution, being most common among adults in the second or fifth decades of life (1) . It is believed that the neoplasm arises from the olfactory epithelium, originating in the superior portion of the nasal cavities, ascending across the cribriform plate, and extending into the anterior cranial fossa (2) .
Clinically, olfactory neuroblastoma manifests as nasal obstruction or epistaxis. It can show indolent behavior, promote local invasion, and generate distant metastases. It tends to invade the paranasal sinuses, orbits, and anterior cranial fossa. The most common metastases are to the lymph nodes of the neck, lungs, liver, and bone, such dissemination at the time of diagnosis being the main predictor of survival (2) . Although there is no universally accepted staging system, the Kadish classification system, established in 1976 and considered an important prognostic predictor, is widely used. In the Kadish system, stage A indicates that the tumor is limited to the nasal cavity; stage B indicates that it involves only the nasal cavity and paranasal sinuses; and stage C indicates that it extends beyond the stage B limits. The staging system proposed by Dulguerov employs the tumor-node-metastasis classifi cation (3,4) .
Bone destruction and calcifi cation within the lesion can be characterized by CT (5) . An MRI scan provides more accurate information on the extent of the tumor, especially in terms of intracranial and orbital involvement. On MRI, the majority of olfactory neuroblastomas present a signal that is (in relation to that of muscle tissue) hypointense in T1-weighted sequences and hyperintense in T2-weighted sequences, as well as showing intense enhancement in contrast-enhanced sequences (6,7) . MRI is also superior to CT in the evaluation of recurrence after craniofacial resection, because of its greater ability to differentiate fi brous scar tissue from residual or recurring neoplasia (6) . Cysts in the intracranial margin of the tumor have been reported in cases of olfactory neuroblastoma. Another relevant aspect is a dumbbell-like morphology, the tumor mass being divided between the anterior cranial fossa and the nasal cavity, the cribriform plate forming the "waist" (5) .
The main differential diagnoses of olfactory neuroblastoma include: squamous cell carcinoma, typically in the maxillary antrum, with bone erosion; sinonasal adenocarcinoma, with heterogeneous enhancement, which has been associated with occupational exposure to wood dust; undifferentiated sinonasal carcinoma, which affects older patients; and dural-based invasive meningioma, with poorly defi ned borders and areas of necrosis (8) . Giant ovarian teratoma: an important differential diagnosis of pelvic masses in children Dear Editor, An 8-year-old female patient presented with diffuse abdominal pain accompanied by progressive distension. Physical examination revealed a large abdominal mass, predominantly in the mesogastrium, that was depressible and painless on palpation. Ultrasound showed a solid-cystic formation extending from the epigastrium to the hypogastrium, with a calcium component and an air-fl uid level (Figure 1). Computed tomography (CT) showed a massive solid-cystic formation, with a fat component and soft tissue, as well as calcifi cations, measuring 12.6 × 19.2 × 20.8 cm, exerting a signifi cant mass effect, displacing the small intestine, aorta, and inferior vena cava, as well as causing slight compression of the pancreas, kidneys, and ureters, with no apparent signs of infi ltration ( Figure 2). Intraoperatively, the mass was seen to be adhered to the left fallopian tube and to the greater omentum ( Figure 1). The tumor was excised without complications, and the patient was discharged fi ve days later. A follow-up abdominal ultrasound revealed no changes.
The occurrence of an abdominal mass in a child should always be evaluated by a pediatrician. The main differential diagnoses are organomegaly and fecal impaction. When abdominal palpation produces nonspecifi c fi ndings, further investigation, employing imaging methods, is required (1) .