Olfactory Neuroblastoma in Children and Adolescents: The EXPeRT recommendations for diagnosis and management

Olfactory neuroblastoma (ON) is a rare tumor commonly presenting between 50 and 60 years of age. In pediatric age this tumor is even rarer, with an estimated incidence of 0.1 per 100,000 children up to 15 years. It arises from the olfactory neurorepithelium of the nasal cavity, and it can be locally aggressive, spreading to the orbital cavity, skull base, intracranial cavity. In rarer cases it can also give distant metastasis, more frequently to regional lymph nodes and less commonly to distant sites like liver, lungs and bones. Prognosis varies depending on the stage at presentation (including dural invasion, regional nodal involvement, and distant metastasis), the histological grade, and aspects related to the treatment, such as the possibility to achieve clear margins with surgery and the multimodal approach. Chemotherapy, surgery and radiotherapy have been used to treat these patients and the different approaches have been reported in the literature. Given the rarity of the disease no shared guidelines exist for the management of this entity in children, but some suggestions can be given to optimize the ON management. This study presents the internationally recognized recommendations for the diagnosis and treatment of ON in children and adolescents, established by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT) group within the EU-funded project Paediatric Rare Tumours Network - European Registry (PARTNER).