Objectives: We assessed the long-term efficacy and toxicity of conservative surgery and radiotherapy in the control of pituitary adenomas.
Design: Retrospective study of patients treated at the Royal Marsden Hospital.
Patients: Four hundred and eleven patients with pituitary adenomas treated with conventional external beam radiotherapy at the Royal Marsden Hospital between 1962 and 1986. Two hundred and fifty-two patients had clinically non-functioning pituitary adenomas, 131 had hormone secreting tumours and in 28 patients the secretory status was not known. Three hundred and thirty-eight patients had surgical intervention of whom only 11 had complete tumour excision. All patients received conventional fractionated external beam radiotherapy to a dose of 45-50Gy in 25-30 fractions.
Measurements: Actuarial progression free survival and overall survival and assessment of toxicity, particularly in terms of vision, requirement for hormone replacement therapy and incidence of second tumours.
Results: The actuarial progression free survival was 94% at 10 years and 88% at 20 years for all patients and 97% at 10 years and 92% at 20 years for patients with clinically non-functioning adenomas. Only secretory status was an independent prognostic factor for disease control. The 10 and 20-year survivals for all patients were 77 and 58% respectively. When compared with the normal population the relative risk of death was 1.76 (P < 0.001) and no prognostic factors for survival were identified. The morbidity of radiotherapy was low. Visual deterioration, assumed to be radiation induced, occurred in 1.5% of patients and the risk of second brain tumour was 1.9% at 20 years. Fifty per cent of patients received hormone replacement therapy by 19 years.
Conclusion: Conventional external beam radiotherapy as described here combined with conservative surgery is safe and effective in the control of pituitary adenomas. These results should form a baseline for comparison with new treatment strategies.