Postoperative Cavity Stereotactic Radiosurgery for Brain Metastases.

During the past decade, tumor bed stereotactic radiosurgery (SRS) after surgical resection has been increasingly utilized in the management of brain metastases. SRS has risen as an alternative to adjuvant whole brain radiation therapy (WBRT), which has been shown in several studies to be associated with increased neurotoxicity. Multiple recent articles have shown favorable local control rates compared to those of WBRT. Specifically, improvements in local control can be achieved by adding a 2 mm margin around the resection cavity. Risk factors that have been established as increasing the risk of local recurrence after resection include: subtotal resection, larger treatment volume, lower margin dose, and a long delay between surgery and SRS (>3 weeks). Moreover, consensus among experts in the field have established the importance of (a) fusion of the pre-operative magnetic resonance imaging scan to aid in volume delineation (b) contouring the entire surgical tract and (c) expanding the target to include possible microscopic disease that may extend to meningeal or venous sinus territory. These strategies can minimize the risks of symptomatic radiation-induced injury and leptomeningeal dissemination after postoperative SRS. Emerging data has arisen suggesting that multifraction postoperative SRS, or alternatively, preoperative SRS could provide decreased rates of radiation necrosis and leptomeningeal disease. Future prospective randomized clinical trials comparing outcomes between these techniques are necessary in order to improve outcomes in these patients.

Stereotactic radiosurgery for brain metastases from malignant melanoma and the impact of hemorrhagic metastases.

INTRODUCTION: Stereotactic radiosurgery (SRS) is a common treatment modality among patients with brain metastases, particularly from malignant melanoma. Our objective was to investigate the difference in local control, toxicity, and survival among patients with hemorrhagic and solid melanoma brain metastases. METHODS: We collected demographic, treatment, local control, toxicity, and survival for 134 patients with a total of 936 intracranial melanoma metastases who underwent SRS between 1998 and 2015. Pre-radiosurgical diagnostic imaging was reviewed for evidence of hemorrhage (melanin-containing or clearly hemorrhagic). RESULTS: The cohort consisted of 92 men and 42 women with a mea age of 61.7 years (range 21.2-84.9) at the time of radiosurgery. Overall survival of patients with brain metastases from malignant melanoma was 42, 31, 12% at 12, 24, and 72 months from date of first SRS. At 6 months, 43% of the patients with hemorrhagic metastases had local tumor control compared to 83% of solid melanoma metastases (p < 0.001). No significant difference in toxicity was noted between the two groups. Factors that were significantly associated with time to local tumor progression on multivariate analysis include prior WBRT (HR 1.62, p = 0.003), prior chemotherapy (HR 0.69, p = 0.011), margin dose (HR 0.88, p < 0.001) and radiographic features of melanin deposition (HR 3.73, p < 0.001), or clear hemorrhage (HR 2.20, p < 0.001). CONCLUSIONS: Our findings demonstrate that hemorrhagic intracranial melanoma metastases are associated with inferior local tumor control when treated with SRS, as compared to solid tumors. These results highlight the importance of early radiosurgery among patients with melanoma brain metastases before hemorrhage occurs.

Management and Survival of Adult Patients with Pilocytic Astrocytoma in the National Cancer Database.

BACKGROUND: Adult pilocytic astrocytomas (PAs) are relatively rare central nervous system (CNS) tumors with a favorable prognosis. We sought to investigate existing clinical management strategies and overall survival (OS) as a function of various clinical characteristics in a cohort of adult patients with PA. METHODS: The study cohort comprised all patients age >18 years diagnosed with a CNS PA diagnosed between 2004 and 2014 and included in the National Cancer Database. Clinical and treatment-related characteristics were recorded and analyzed for associations with OS following diagnosis using univariate and multivariate analyses. RESULTS: A total of 3057 adult patients, with a median age of 32 years, met the inclusion criteria. At diagnosis, 1138 patients (41%) had cerebral tumors, 832 (30%) had cerebellar tumors, 252 (9%) had tumors of the spinal cord, and 534 (19%) had tumors of unspecified location. More than three-quarters (77%) of the patients underwent surgery alone as local therapy, with the remainder split among surgery plus radiation (11.9%), radiation alone (4.5%), and biopsy alone (6.9%). On multivariate analysis, factors associated with inferior OS included older age (hazard ratio [HR], 1.05; P < 0.001), lower income (P < 0.001), higher Charlson/Deyo score (P = 0.023), larger tumor size (P = 0.023), and radiation therapy technique (P < 0.001; HR, 3.37 for external beam radiation therapy [EBRT]). CONCLUSIONS: Our data provide large-scale prognostic information from a contemporary cohort of patients with PA, confirming that age, median income, Charlson/Deyo Score, and tumor size have significant effects on OS. Although resection status, tumor size, and location likely bias against EBRT, novel therapeutics are clearly needed in patients with tumors not amenable to resection or radiosurgery.