Radiosurgery for Patients with More Than Ten Brain Metastases.

Purpose In this article, we report on Gamma Knife radiosurgery performed on patients with more than 10 brain metastases. Although the standard treatment for multiple brain metastases is currently believed to be whole-brain irradiation, many patients are averse to it due to the potential for serious complications such as cognitive impairment. Cases and Methods Here, 70 cases of Gamma Knife radiosurgery for metastatic foci originating from various primary cancer are reviewed. Several different treatment protocols were selected: (1) single session, (2) two or three consecutive sessions, (3) fractionated irradiation for large tumor and stereotactic radiosurgery (SRS) for small ones, and (4) salvage treatment for recurrent tumors after whole-brain irradiation. Results Despite the long beam-on-time (BOT) necessary for Gamma Knife radiosurgery and unavoidable spillage irradiation to the entire brain, all the treatments were completed without any major difficulties. Conclusion SRS or radiotherapy might be a treatment choice for patients with more than 10 brain metastases. However, the very long treatment time and big spillage irradiation to the entire brain warrants that large metastatic foci should be removed before or after radiosurgery.