Stereotactic radiosurgery and radiotherapy for meningiomas: biomarker predictors of patient outcome and response to therapy.

Although surgery has traditionally been the primary treatment of meningiomas, stereotactic radiosurgery (SRS) and radiotherapy (SRT) techniques have become a standard part of the treatment approach to intracranial meningiomas. For incompletely resected or inoperable benign meningiomas, SRT and SRS can provide excellent 5-year tumor control rates in 90% to 95% of benign meningioma cases. The current data on prognostic factors in meningioma SRT and SRS treatment outcomes are sparse. Our study aims to define prognostic factors that may help determine meningioma SRT and SRS treatment outcomes. Outcomes of 162 patients with 166 intracranial meningiomas treated with SRT (80 treatments) or SRS (92 treatments) were examined. Patient characteristics and tumor hypoxia-regulated biomarkers were correlated with tumor local control and overall survival. Median follow-up was 52 months, with median tumor volumes and treatment doses of 2.72 cm3/15 Gy and 12.54 cm3/54 Gy for SRS- and SRT-treated patients, respectively. Local control occurred in 68/77 (88.3%) SRT-treated patients and 80/89 (89.9%) SRS-treated patients. Tumor volume was predictive of overall survival for patients treated with SRT. The hypoxia-related biomarkers VEGF, HIF-1, and MIB-1 were useful in predicting outcome after SRT and SRS. SRS and SRT are successful in controlling intracranial meningioma growth. With further study, HIF-1, VEGF, and MIB-1 may be useful as predictive markers for response to SRT and SRS.

Overall and progression-free survival and visual and endocrine outcomes for patients with parasellar lesions treated with intensity-modulated stereotactic radiosurgery.

Linear accelerator single-fraction radiosurgery (SRS) for skull base lesions is usually delivered with dynamic conformal arcs (DCAs), but intensity-modulated radiosurgery (IMRS) is another option when SRS dose is limited by proximity of the optic nerve and chiasm. We review the long-term outcome of patients treated with IMRS for parasellar lesions. Fourteen patients with parasellar lesions were treated with IMRS when standard DCA radiosurgery was limited by optic nerve tolerance. Prospective patient data included endocrine function, visual acuity and field testing, nonoptic nerve cranial neuropathy, and overall survival. In addition, tumor control on serial magnetic resonance imaging is reported as progression-free survival (PFS). Six patients with cavernous sinus meningiomas and eight with recurrent pituitary adenomas were treated. Three of the pituitary tumors were hormonally active (two with Cushing disease, one with acromegaly). The median patient age was 50 years (range 24-70 years). Median follow-up was 54 months. Average tumor treatment volume was 4.99 ml (average dose 16 Gy, average of 10 IMRS fields). Tumor control was achieved in 11 of 14 (79%) patients. Median PFS has not been reached in our patient population. Thirteen patients are alive (one died of an unrelated cancer). No patients developed new endocrinological, ophthalmological, or cranial nerve deficits. IMRS allows for treatment of parasellar lesions when standard DCA SRS is limited by optic nerve tolerance. Although our follow-up period was relatively short and the number of patients was small, it appears that this can be accomplished with a high tumor control rate and survival without new endocrinopathies, optic neuropathies, or other complications in patients who have failed other therapies.

Multidisciplinary treatment of brain metastases derived from clear cell renal cancer incorporating stereotactic radiosurgery.

BACKGROUND: Brain metastases are a frequent complication in patients with metastatic clear cell renal cancer. Survival after whole-brain radiotherapy (WBRT) is disappointing. A retrospective analysis of multimodality treatment was performed in patients who had received linear accelerator (LINAC)-based stereotactic radiosurgery (SRS). METHODS: Thirty-two patients underwent SRS-based treatment for 71 metastatic foci between 2000 and 2006. All patients had a Karnofsky performance status >or=70 and all 32 patients had extracranial metastatic disease (Radiation Therapy Oncology Group recursive partitioning analysis [RPA] Class 2). Survival was calculated from the time of diagnosis of brain metastases. The minimum potential follow-up was 1 year after SRS. Univariate and multivariate analysis of potential prognostic factors affecting survival was performed. RESULTS: Twenty-six patients required only 1 SRS treatment (84%) to achieve central nervous system (CNS) control, whereas 5 patients received 2 to 3 treatments (16%). The median survival of renal cancer patients from the diagnosis of brain metastases was 10.1 months (95% confidence interval, 6.4-14.8 months). One-year and 3-year survival rates were 43% and 16%, respectively. The addition of surgery or WBRT did not appear to prolong survival. Immunotherapy after control of brain metastases with SRS appeared to result in significantly improved survival. Survival was also found to be strongly influenced by prognostic stratification of metastatic disease using Motzer or modified risk criteria. CONCLUSIONS: The results of the current study demonstrated that SRS-based treatment of patients with up to 5 brain metastases from clear cell renal cancer is feasible and results in excellent CNS control. Survival beyond 3 years from the time of diagnosis of brain metastases was achievable in 16% of patients and was associated with the use of systemic immunotherapy with interleukin-2 and interferon but not antiangiogenic agents.