Olfactory neuroblastoma is a rare, slow growing, malignant tumour of neuroectodermal origin that begins in neuroepithelial cells of the olfactory membrane. A metastatic rate of 20% to 60% is reported with the most common site being the cervical lymph node. Other sites include the parotid glands, skin, lungs, bone, liver, orbit, spinal cord and spinal canal. We describe a case of olfactory neuroblastoma presented to us with scalp metastasis.
Esthesioneuroblastoma is a rare malignant neoplasm of oflactory neuroepithelium and usually located at the olfactory cleft at superior nasal cavity. Ectopic localization of esthesioneuroblastoma is even rarer and usually posed with a diagnostic dilemma and delay in the diagnosis and management, We report a rare case of ectopic esthesioneuroblastoma of the sphenoclivus with the presentation of intermittent unilateral epistaxis, intermittent intractable headache without anosmia. Nasal endoscopy findings showed a pulsatile mass at the anterior face of the sphenoid sinus with extension posteriorly towards the clivus region and occupying the floor of the sphenoid sinus. Endonasal transclival endoscopic excision of tumour was performed which involved otorhinolaryngology surgeon and neurosurgeon with intraoperative navigation imaging and frozen section. The histopathological findings was esthesioneuroblastoma. Due to its rarity and unusual presentation, the diagnosis of ectopic esthesioneuroblastoma is difficult and can be misdiagnosed with the other type of malignancy. Therefore, the histopathological result is important in confirming the type of tumour and can lead to the next step of management.
We present our experience in managing pathologies involving the anterior and middle cranial base using an endoscopic transnasal approach, highlighting the surgical technique, indications, and complications. The different types of endoscopic approaches used include the transtuberculum/transplanum, transcribiform, transsellar, and cavernous sinus approaches. The common indications include repair of cerebrospinal fluid leaks (both spontaneous and post traumatic) and excision of pituitary adenomas, meningiomas, craniopharyngiomas, esthesioneuroblastomas, and other malignancies of the anterior cranial base. Careful reconstruction is performed with the multilayer technique utilizing fat, fascia lata, and fibrin sealant. The endoscopic transnasal approach, coupled with the present-day sophisticated neuronavigation systems, allows access to lesions in the midline extending from the cribriform plate to the craniovertebral junction. However, preoperative planning and careful selection of cases with evaluation of each case on an individual basis with regard to the lateral extension of the lesion are imperative.