Faculty Bibliography

The purpose of this study was to devise a new recursive partitioning analysis (RPA) of patients with four or more intracranial metastases treated with a single radiosurgery procedure to identify a class of patients with extended survival. 205 patients underwent Gamma Knife radiosurgery for four or more intracranial metastases (median = 5, range 4-18) during one session. The median total treatment volume was 6.8 cc (range 0.6-51.0 cc). Radiosurgery was used as sole management (17% of patients), or in combination with WB-RT (46%), or after failure of WB-RT (38%). The median marginal radiosurgery dose was 16 Gy (range 12-20 Gy). RPA assessed the effects of age, Karnofsky >70, extracranial disease, visceral metastases, number of metastases, total treatment volume, history of breast and melanoma primaries on survival. The median overall survival after radiosurgery for all patients was 8 months. RPA identified a favorable subgroup of 78 patients (43% of the series) with a total treatment volume <7 cc and < 7 brain metastases (Class 1), with a median survival of 13 months. This subgroup's survival was significantly better (p <0.00005) than the remaining patients (Class 2) (n=111) with a median survival of 6 months. In conclusion, RPA of multiple brain metastasis patients identified 2 distinct cohorts of patients. Class 1 patients have a total treatment volume <7 cc and < 7 metastases (4-6) with favorable survival after Radiosurgery and Class 2 patients have a total treatment volume > or = 7 cc and/or > or = 7 metastases and have a significantly poorer survival.

OBJECTIVE: Radiosurgery is increasingly used to manage malignant melanoma brain metastases. We reviewed our series of patients who underwent radiosurgery for melanoma brain metastases to assess clinical outcomes and identify prognostic factors for survival and cerebral disease control. METHODS: Two hundred forty-four patients had radiosurgery for the management of 754 metastatic tumors. A mean of 2.6 tumors were irradiated per procedure. The median tumor volume was 4.4 cm3. The median margin and maximum doses used were 18 and 32 Gy, respectively. RESULTS: The median survival was 5.3 months after radiosurgery (mean, 10 mo; range, 0.2-114.3 mo). Patients survived a median of 7.8 months (mean, 13.4 mo) from the diagnosis of brain metastases and 44.9 months (mean, 69 mo) after the diagnosis of the primary tumor. Survival was better in patients with controlled systemic disease (12.7 mo), single brain metastasis (6.8 mo), and a Karnofsky performance score of 90 or 100% (6.3 mo). Sustained local control was achieved in 86.2% of tumors. Increased tumor volume and previous evidence of hemorrhage increased the risk of local failure. Multiple lesions and failure to provide systemic immunotherapy were predictors for the occurrence of new brain metastases, which developed in 41.7% of the patients. Symptomatic radiation changes occurred in 6.6% of the patients. Overall, 71.4% of the patients improved or remained clinically stable. Brain disease was the cause of death in 40.5% of the patients, usually from the development of new metastases. CONCLUSION: Gamma knife radiosurgery for malignant melanoma brain metastases is safe and effective and provides a high rate of durable local control. Improved survival can be achieved in patients with single metastasis, controlled systemic disease, and a high Karnofsky performance score.