Radiosurgical Treatment of Recurrent Esthesioneuroblastoma: Case Report

Esthesioneuroblastoma is an uncommon neuroectodermal tumor occurring with an incidence of 0.4 per 1 million and constitutes approximately 2-3% of sinonasal malignancies with no gender predilection [1,2]. ENB was first described by Berger et al. [3] in 1924 and since then approximately 1200 cases have been reported [3,4]. The tumor arises from basal stem cells of sensory olfactory epithelium locating on superior nasal structures, cribriform plate and anterior skull base [4,5]. The most common symptoms are nasal congestion and epistaxis, anosmia, rhinorrhea or lacrimation [6]. Late clinical manifestation resulting from asymptomatic behavior of the tumor on early stages leads to high rate skull base involvement. Therefore the primary treatment modality is often a craniofacial resection, adjuvant external beam radiotherapy and chemotherapy [7]. Despite combined treatment the risk of local recurrence is about 20-50% [4-7]. Appliance of stereotactic radiosurgery (SRS) as a non-invasive treatment modality can be safe and effective in group of patients with local recurrence of ENB after surgery, especially in cases of deep located lesions. Here we present our experience of Gamma Knife SRS for an aggressive Kadish stage C (‘spread beyond nasal and paranasal cavities’) esthesioneuroblastoma involving right orbit, anterior cranial fossa and sphenopetroclival region.