Surgical Treatment for Multiple Brain Metastases

Brain metastasis occurs with a fairly high frequency, in 25–35% of cancer patients [1]. Be‐ cause brain metastasis directly affects prognosis, quality of life (QOL), and performance status (PS), treatment is crucial. Survival time is reported to be 1 month in the case of untreated brain metastasis [2], 2 months with steroid treatment alone [3], and 3-6 months with whole-brain radiotherapy (WBRT) [4-7]. This shows that brain metastasis is a seri‐ ously life-threatening condition. Therapeutic approaches have become more varied with the appearance of stereotactic radiosurgery (SRS), and establishment of multiple treat‐ ment plans has become possible. In addition to surgical resection (SR), WBRT, and SRS, systemic chemotherapy (SC) is also an option. The ideal treatment is to control the brain metastasis and prevent destruction of the central nervous system using combinations of these therapeutic approaches. Among these multiple approaches, SR is effective in that it enables treatment of large tumors and early improvement of symptoms, which are not possible with other approaches. The indications for SR are expanded with the early im‐ provement of symptoms, leading particularly to improved QOL from the palliative view‐ point. However, SR is also highly invasive compared with other treatments, and the indications are strict. The standard surgical indication is single brain metastasis, and pa‐ tients with fairly good prognosis, such as those with good general condition, are selected [8]. Recently, however, partly as a result of advances in imaging, the number of cases of multiple brain metastases has been trending upward. This means that there are patients in whom SR is excluded as an indication because of findings for multiple brain metasta‐ ses, and who cannot obtain the benefits of surgery. We provide aggressive treatment us‐ ing the same surgical indications for cases of multiple brain metastases as for single metastasis. The present study therefore investigated treatment outcomes and reported on the effectiveness of SR for multiple brain metastases.