Glomus jugulare tumours: certain clinical and radiological aspects observed following Gamma Knife radiosurgery.

INTRODUCTION

Glomus jugulare tumours represent a great therapeutic challenge. Previous papers have documented good results from Gamma Knife surgery (GKS) with these tumours. However, the relationship between clinical improvement and tumour shrinkage has never been assessed.

MATERIALS AND METHODS

There were 14 patients, 9 women and 5 men. The mean follow-up period was 28 months (range 6 to 60 months). All the tumours except one were Fisch type D and the mean volume was 14.2 cm(3) (range 3.7-28.4 cm(3)). The mean prescription dose was 13.6 Gy (range 12-16 Gy).

RESULTS

None of the tumours have continued to grow. Eight are smaller and 6 unchanged in volume. Two patients with bruit have had no improvement in their symptoms. Among the other 12 patients, 5 have had symptomatic improvement of dysphagia, 4 in dysphonia, 3 in facial numbness, 3 in ataxia and 2 in tinnitus. Individual patients have experienced improvement in vomiting, vertigo, tongue fasciculation, hearing, headache, facial palsy and accessory paresis. One patient developed a transient facial palsy. Symptomatic improvement commonly began before any reduction in tumour volume could be detected. The mean time to clinical improvement was 6.5 months whereas the mean time to shrinkage was 13.5 months.

CONCLUSIONS

Gamma Knife treatment of glomus jugulare tumours is associated with a high incidence of clinical improvement with few complications, using the dosimetry recorded here. Clinical improvement would seem to be a more sensitive early indicator of therapeutic success than radiological volume reduction. Further follow-up will be needed.