Fractionated stereotactic radiotherapy in patients with skull base benign tumours: The Royal Marsden Hospital experience

BACKGROUND: Stereotactic radiotherapy techniques have been recently employed in the control of skull base tumours as pituitary adenomas, craniopharyngiomas and meningiomas. OBJECTIVE: to assess the long-term outcome of fractionated stereotactic conformal radiotherapy in patients with residual and recurrent pituitary adenoma treated at Royal Marsden Hospital. PATIENTS AND METHODS: 245 patients with pituitary adenoma (n = 98), meningioma (n = 108) and craniopharyngioma (n = 39) were treated with fractionated stereotactic radiotherapy between 1995 and 2004. Patients were treated with 4-6 non-coplanar conformal fixed fields. Treatment was delivered in 25-33 daily fractions to a dose of 45-55 Gy. Results: the 5-year progression free survival was 98%, 92%, and 90% for pituitary adenoma, meningioma and craniopharyngioma. The respective 5-year survival was 98%, 97% and 100%. Ten patients required further debulking surgery for progressive disease (3 pituitary adenomas, 5 meningiomas and 2 craniopharyngiomas). The treatment was well tolerated with acceptable long-term toxicity. 15% of patients had a clinical improvement in neurological deficits following stereotactic radiotherapy. Hypopituitarism was the most common long-term effect and 33% of patients worsened pituitary function. Three patients had visual deterioration following stereotactic radiotherapy. CONCLUSION: Our results suggest that fractionated stereotactic radiotherapy is a high precise technique suitable for the treatment of skull base tumours with low toxicity. Tumour and hormone control are equivalent to those seen following conventional RT. Longer follow up is needed to assess a potential reduction in long-term morbidity. Copyright © 2007 by new Magazine edizioni s.r.l.