A 46-year-old healthy man visited a local clinic for general weakness and hyposmia and underwent examination with serial endocrinological workup and brain imaging. 68Gallium-DOTATOC positron emission tomography scan was helpful were diagnosis of sellar MRI and inferior petrosal sinus sampling were discordant. Combined transcranial and endoscopic endonasal approach surgery was performed, and a diagnosis of esthesioneuroblastoma was given ¹⁾.

A case of non-contiguous meningeal recurrence of olfactory neuroblastoma presenting as a giant frontal mass. A 66-year-old woman was admitted with a left nasal intranasal localized tumor without cranial extension and gross total removal was achieved. Pathological examination showed olfactory neuroblastoma and radiation therapy was added in a limited region of the removal cavity. Radiological follow-up continued for 10 years and there was no local recurrence. Sixteen years after radiation therapy, the patient found a slight frontal mass gradually growing. Magnetic resonance imaging revealed an enhanced mass lesion of 7 cm in thickness and 9 cm in diameter associated with marked thickness of the frontal bone, intradural cystic mass compressing the bilateral frontal lobe, and no local recurrence. A second operation was performed followed by radiotherapy and we diagnosed no-contiguous meningeal recurrence of metastatic olfactory neuroblastoma. Olfactory neuroblastoma is a locally aggressive tumor. Although metastases of this tumor has been reported, non-contiguous spread to the dura is rare. Understanding the route of remote metastases and careful evaluation after primary treatment are needed to avoid misdiagnosis and treatment delays ²⁾.