Our objective was to review recent developments in diagnosis, staging, and treatment of esthesioneuroblastoma (ENB). A meta-analysis of publications between 1990 and 2000 was carried out, and studies were classified according to their main subject: origin/aetiology of ENB, histopathological diagnosis, and treatment. Data so far point to the basal progenitor cells of the olfactory epithelium as the origin of ENB. Histopathological diagnosis remains difficult and is based on results of antigen expression detected through a panel of antibodies by immunohistochemistry. RT-PCR of HASH expression could be a specific marker of ENB. Overall and disease-free survival at 5 years averaged 45% (SD 22) and 41% (SD 21) in the studies included in the meta-analysis. Survival in Hyams' grades I-II was 56% (SD 20) compared with 25% (SD 20) in grades III-IV (odds ratio 6.2). In patients with metastases in cervical lymph nodes (on average 5% of the total) survival was 29%, compared with 64% for patients with N0 disease (odds ratio 5.1). Survival according to treatment modalities was 65% for surgery plus radiotherapy, 51% for radiotherapy and chemotherapy, 48% for surgery, 47% for surgery plus radiotherapy and chemotherapy, and 37% for radiotherapy alone. The histopathological grading according to Hyams and the presence of cervical lymph-node metastases emerged as prognostic factors. A combination of surgery and radiotherapy seems to be the optimum approach to treatment. The exact role of chemotherapy in treatment protocols is still unclear. The role of elective neck dissection is unclear.