Meningiomas and sex hormones, radiotherapy and benign brain tumours

Abstract

I WELCOME the opportunity to widen this discussion prompted by Drs Costello and Rampling [l]. The use of conventional external beam radiotherapy for meningiomas has not convinced us neurosurgeons, despite the well-known enthusiasm of the late Professor Bloom [2]. I have never seen a meningioma shrink with conventional therapy and of course it is practically impossible to prove that selected, slow-growing tumours, particularly those occurring in the 50+ age group, have responded to this kind of treatment. There is anecdotal evidence that stereotactic radiotherapy has shrunk one or two meningiomas. Radiotherapy is not without side-effects and astute clinicians see from time to time stroke-like episodes occurring in patients with benign brain tumours who have had previous radiotherapy. This controversy also extends to the juvenile cerebellar astrocytomas [3], where the only malignant late recurrences appear to have occurred in patients who had had radiotherapy, low grade ependymomas where the value of radiotherapy may be questioned [4] and of course the low-grade supratentorial astrocytomas where it was proven virtually impossible to select and recruit patients to prospective clinical trials. As a neurosurgeon, conventional radiotherapy for these problem tumours has, I feel, on occasion been the refuge of the destitute rather than a therapy. It is now over a 100 years since the founder of neurosurgery, MacEwan, removed the first meningioma in Glasgow and we hope that our radiotherapy colleagues will be able to improve the treatment of “benign” brain tumours.