Malignant glomus tumors.

OBJECTIVES/HYPOTHESIS: To ascertain the incidence of malignancy in a large glomus and skull base series and to compare the clinical course of such patients with those who do not have malignant skull base lesions.

STUDY DESIGN: Retrospective review of all skull base surgery cases treated at the Otology Group between 1970 and 1995.

RESULTS: In a series of 175 jugulotympanic glomus tumors, 9 cases (5.1%) were identified. The surgery required for their extirpation is more extensive than nonmalignant glomus tumors. Attendant deficits and mortality from these procedures are accordingly greater. Five-year survival in this limited population was 72%. Prolonged periods of survival are possible with distant metastases.

CONCLUSIONS: This rate of malignancy should advocate against a watchful, waiting approach. Radiation therapy is not advocated as a primary modality for this type of tumor, as it may lead to recurrence/persistence with either subsequent malignant degeneration and metastases or local recurrence.