Summary
Esthesioneuroblastoma or olfactory neuroblastoma is a very rare tumour originating from olfactory cells in the nasal cavity. Only around 1000 cases have been reported in the last twenty years. Age distribution is bimodal with two peaks at around 20 and 50 years of age. This tumour grows slowly, mainly locally but distant metastatic spread to cervical lymph nodes, lungs, bones and brain may occur. The interval between the first sign and diagnosis is usually around 6 months. Symptoms are not specific but the two most frequent manifestations include unilateral nasal obstruction and epistaxis. The causes of this tumour are unknown but the most frequent genetic abnormalities are loss of chromosome 3p and gain of chromosome 17q. Early detection may enable en bloc tumour resection which is an important prognostic factor. Other factors correlated with a good prognosis are young age, absence of spread beyond the paranasal sinuses (stage A of the Kadish classification) and low histological grade (Hyams grading). Treatment consists of maximal surgical resection followed by radiotherapy. Chemotherapy can be used for tumour reduction before surgery and to treat metastasis; its efficacy is recognized but its use is still under discussion. Olfactory function is usually lost or altered after surgery. Most of the recent series report survival rates of approximately 60 to 70% at 5 years. Local relapses can be rescued by second-line treatment including intensive chemotherapy. From the time of diagnosis and initial surgery, management of these patients should be carried out by multidisciplinary teams with expertise in oncology within prospective studies aiming to improve patient's survival and quality of life. *Author: Dr J. Grill (February 2005)*.
