Esthesioneuroblastoma with intracranial extension

Esthesioneuroblastoma - a clinicopathologic study and role of DNA topoisomerase alpha

Esthesioneuroblastoma (ENB) differs from adrenal neuroblastomas in its histopathologic and biologic characteristics. Hyams grading and Kadish staging have shown correlation with survival. Scant data are available on proliferation indices and prognosis. We retrospectively reviewed the clinicopathologic characteristics of ENB. Both Kadish and UCLA staging systems were used. Hyams grading was simplified into low and high grade. DNA topoisomerase II alpha labeling index (T2alpha LI) was obtained in 8 cases using immunohistochemistry. Of the 19 cases studied, 14 were males and 5 females. Age range was 2 to 62 years (average 27 years). The mass primarily involved the nose in 12 (63%) and paranasal sinuses in 7 cases (37%). Patients presented with nose block in 19 (100%), epistaxis in 10 (53%), proptosis in 9 (47%) and loss of vision in 6 cases (32%). Bony involvement was seen in 7 cases (37%), and intracranial spread in one case (5%). Thirteen (68%) were low-grade tumors and 6 were (32%) high-grade. There was no statistically significant difference between the low- and high-grade ENB in age (years) (p=0.2882), duration of symptoms (months) (p=0.5636), and either in the Kadish (p=0.5456) or the UCLA staging system (p=0.7771). The difference in DNA topoisomerase alpha labeling index between the low- and highgrade ENB (medians: 10.4 and 22.3, respectively) was not statistically significant (p=0.0714), but it was suggestive of a positive association. The results of this study should be interpreted with caution, because of the limited sample size. Three cases recurred locally, one each stage A, B and C, but all low-grade. This preliminary study suggests the need to combine a simplified histologic grading with accurate staging in a reasonable attempt to assess local progression in esthesioneuroblastoma. Larger studies may clarify the role of T2alpha LI in improving histologic grading.

Olfactory neuroblastomas: survival rate and prognostic factor

Olfactory neuroblastomas are known to be rare and clinically malignant tumors. The authors analyzed the clinical features, long-term treatment outcomes, and prognostic factors related to 21 cases of olfactory neuroblastomas, treated between January 1979 and October 2000, retrospectively reviewed with medical records and radiologic findings. The mean follow-up period was 28.7 months (range 4-178). The extent of tumor was classified according to the UCLA staging system. Statistical analysis for survival was done using the Kaplan-Meier method and the log-rank test. The mean age was 27 years (13-62), the peak incidence occurred in the second decade (8/21, 38%), and the male to female ratio was 13:8. According to the UCLA staging system, there were 3 cases of T1, 5 of T2, 6 of T3, and 7 of T4. The 5-year survival rate was 21.3% and the average survival time was 28.9 months. The group (n = 14) undergoing radical surgical resection as the primary modality, registered a higher survival rate than the radiation and chemotherapy group (n = 7), with 2-year survival rates being 76.2% vs. 14.3%, respectively (p = 0.0274). The early stage (T1, T2) groups exhibited a better survival rate than the advanced (T3, T4) groups with 5-year survival rates being 38.1% vs. 9.1%, respectively (p = 0.0336). The mean recurrence free time was 7.8 months (range 1-25). From these findings we could conclude that tumor detection in the early stage, radical surgical resection as the primary treatment modality, and regular follow-up with radiologic evaluation for recurrence or metastasis, represent important factors for an improved outcome.

Review of skull base surgery approaches: with special reference to pediatric patients

The techniques of skull base surgery attempt to maximize the exposure of a cranial base lesion while using the least amount of brain retraction. Cranial base surgery is not a 'new' area of neurosurgical or otolaryngologic interest, but instead represents a resurgence of efforts to treat difficult lesions involving the cranial base. This resurgence of interest and effort is a product of recent advances in microanatomical knowledge of the cranial base, advances in microsurgical technique, improved neurophysiologic monitoring, and improved collaborative relationships between neurosurgery, otolaryngology and plastic surgery. Furthermore, improved neuroanesthetic techniques allow the surgeon to proceed with surgery without undue concern about time, and improved neuroimaging techniques provide the surgeon with detailed knowledge of the three dimensional characteristics of the tumor and surrounding structures. This review will focus on the surgical management of cranial base tumors primarily affecting the pediatric population. Little has been written on the techniques of skull base surgery as they apply to the pediatric population, since cranially-based tumors are a relatively rare occurrence in this patient population. In most instances, however, many of the 'standard' skull base approaches can be applied to the pediatric patient with few modifications, and in our experience, the pediatric patients have tolerated these approaches as well as their adult counterparts.