Local recurrence of metastatic brain tumor after stereotactic radiosurgery or surgery plus radiation.

In this study, we compared the recurrence of metastatic brain tumors after radiosurgery versus after surgery plus radiation, and analyzed the factors associated with the recurrence of brain metastases. Twenty-eight and 35 patients with metastatic brain tumors underwent radiosurgery (52 lesions) and surgery plus radiation (46 lesions), respectively, between 1995 and 2001. The median tumor volume was 1.55 ml (range: 0.02-10.4 ml) in radiosurgery patients and 17.9 ml (range: 0.26-195 ml) in surgery plus radiation patients. The median radiosurgical tumor central and margin doses were 28.9 and 23.8 Gy (range: 20-35 and 25-15 Gy), respectively. The median total dose was 46.7 Gy (range: 30-63 Gy) in the surgery plus radiation group. The recurrence time from surgery plus radiation group (25 months) was significantly longer than that from the radiosurgery group (7.2 months) (p = 0.0199). The factors affecting the recurrence of brain metastases after radiosurgery were size, central dose of radiation and histology (colon vs. others). No factors affected the recurrence of brain metastases after surgery plus radiation. To avoid early recurrences of metastatic brain tumors, surgery plus radiation is the preferable therapeutic modality. The size and histology of brain metastases, and the dose of radiation should be considered for the effective treatment of tumors by radiosurgery.