Because of the high frequency of brain metastases in small cell lung cancer, especially in patients with prolonged survival, prophylactic radiation of the head has been used by many physicians. This reduces the frequency of subsequent brain metastases, especially in patients with complete responses to therapy, but has not been shown to influence survival. There may be late complications of this type of treatment, with significant neurologic, mental and thinking deficits in some long-term survivors who were given high daily dose fractionation. It may be preferable to give smaller doses each day.
It must also be emphasized that many treatment centers do not recommend the use of prophylactic brain irradiation because there has not been ample proof of a survival benefit and there is a valid concern about the neurologic side effects of the treatment. If necessary, radiation therapy can be given when the brain metastases are demonstrated to occur.
