The need for adjunctive focused radiation therapy in pituitary adenomas

In pituitary adenomas radiation therapy regardless of the technique should be limited to surgical failures. The delayed onset of beneficial effects and the high rate of pituitary insufficiency have to be weighed against the good surgical and/or medical results in the treatment of these tumours. Unfortunately surgical outcome is almost invariably correlated with invasive growth. Invasiveness is statistically significantly correlated with tumour size, as well as with high proliferation rates, which can be measured by immunohistological methods such as mAB KI-67. Owing to the good results of medical treatment, radiation therapy is usually unnecessary in prolactinomas. Patients with persistent hypersecretion of growth hormone after unsuccessful surgery may represent the ideal candidates for radiation therapy, whereas patients with persistent Cushing's disease need cure for hypercortisolism without delay. In patients with residual tumour due to non functioning adenomas, radiation therapy should only be given if the proliferation rate is high.