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Purpose To assess the role of Gamma Knife radiosurgery (GKRS) in the treatment of nonsurgical cystic brain metastasis, and to determine predictors of response to GKRS. Methods We reviewed a prospectively maintained database of brain metastases patients treated at our institution between 2006 and 2010. All lesions with a cystic component were identified, and volumetric analysis was done to measure percentage of cystic volume on day of treatment and consecutive follow-up MRI scans. Clinical, radiologic, and dosimetry parameters were reviewed to establish the overall response of cystic metastases to GKRS as well as identify potential predictive factors of response. Results A total of 111 lesions in 73 patients were analyzed; 57% of lesions received prior whole-brain radiation therapy (WBRT). Lung carcinoma was the primary cancer in 51% of patients, 10% breast, 10% colorectal, 4% melanoma, and 26% other. Fifty-seven percent of the patients were recursive partitioning analysis class 1, the remainder class 2. Mean target volume was 3.3 mL (range, 0.1-23 mL). Median prescription dose was 21 Gy (range, 15-24 Gy). Local control rates were 91%, 63%, and 37% at 6, 12, and 18 months, respectively. Local control was improved in lung primary and worse in patients with prior WBRT (univariate). Only lung primary predicted local control in multivariate analysis, whereas age and tumor volume did not. Lesions with a large cystic component did not show a poorer response compared with those with a small cystic component. Conclusions This study supports the use of GKRS in the management of nonsurgical cystic metastases, despite a traditionally perceived poorer response. Our local control rates are comparable to a matched cohort of noncystic brain metastases, and therefore the presence of a large cystic component should not deter the use of GKRS. Predictors of response included tumor subtype. Prior WBRT decreased effectiveness of SRS for local control rates.

Renal cell carcinoma (RCC) and melanoma brain metastases have traditionally been considered radioresistant lesions when treated with conventional radiotherapeutic modalities. Radiosurgery provides high-dose radiation to a defined target volume with steep fall off in dose at lesion margins. Recent evidence suggests that stereotactic radiosurgery (SRS) is effective in improving local control and overall survival for a number of tumor subtypes including RCC and melanoma brain metastases. The purpose of this study was to compare the response rate to SRS between RCC and melanoma patients and to identify predictors of response to SRS for these 2 specific subtypes of brain metastases. We retrospectively reviewed a prospectively maintained database of all brain metastases treated with Gamma Knife SRS at the University Health Network (Toronto, Ontario) between October 2007 and June 2010, studying RCC and melanoma patients. Demographics, treatment history and dosimetry data were collected; and MRIs were reviewed for treatment response. Log rank, Cox proportional hazard ratio and Kaplan-Meier survival analysis using SPSS were performed. A total of 103 brain metastases patients (41 RCC; 62 melanoma) were included in the study. The median age, Karnofsky performance status score and Eastern Cooperative Oncology Group performance score was 52 years (range 27-81), 90 (range 70-100) and 1 (range 0-2), respectively. Thirty-four lesions received adjuvant chemotherapy and 56 received pre-SRS whole brain radiation therapy. The median follow-up, prescription dose, Radiation Therapy Oncology Group conformity index, target volume and number of shots was 6 months (range 1-41 months), 21 Gy (range 15-25 Gy), 1.93 (range 1.04-9.76), 0.4 cm3 (range 0.005-13.36 cm3) and 2 (range 1-22), respectively. Smaller tumor volume (P=0.007) and RCC pathology (P=0.04) were found to be positive predictors of response. Actuarial local control rate for RCC and melanoma combined was 89% at 6 months, 84% at 12 months, 76% at 18 months and 61% at 24 months. Local control at 12 months was 91 and 75% for RCC and melanoma, respectively. SRS is a valuable treatment option for local control of RCC and melanoma brain metastases. Smaller tumor volume and RCC pathology, predictors of response, suggest distinct differences in tumor biology and the extent of radioresponse between RCC and melanoma.

Background Microscopic and endoscopic approaches are both utilized for transsphenoidal resection of sellar/parasellar lesions. The endoscopic approach has been gaining popularity over the past decade; however, quality-of-life studies comparing the microscopic and endoscopic approaches are lacking. We aimed to compare the patients’ perceptions of their postoperative recovery periods following microscopic and endoscopic procedures. Methods Qualitative research methodology was used for this study. Each participant underwent a single semi-structured, open-ended interview based on an interview guide. Each participant had undergone at least one microscopic and one endoscopictranssphenoidal procedurefor resectionofa sellar/ parasellar lesion. The interviews were audiotaped and transcribed. The transcripts were then analyzed for overarching themes. Demographic information was also collected. Results The following five overarching themes emerged from the data: (1) the endoscopic procedure was better tolerated than the microscopic procedure and was the preferred approach by 22 out of 27 patients should they require another surgery in the future; (2) most patients did not know that they had undergone two different surgical approaches; (3) other than an unpleasant malodorous smell, rhinologic complications (including drainage, crusting, and alterations in smell) following the endoscopic procedures were comparable to those following the microscopic procedures; (4) the patient’s postoperative experience after the microscopic procedure had an impact on his/her expectations of the endoscopic procedure; (5) any significant pain or discomfort experienced from either procedure was mainly related to the nasal packing or fascia lata graft donor site. Conclusions The endoscopic procedure was the preferred approach over the microscopic approach by the majority of patients because of its better tolerability, despite comparable rhinologic complications.

Endoscopic transsphenoidal surgery has been shown to be a safe and effective treatment option for patients with pituitary tumours, but no study has explored patients' perceptions before and after this surgery.The authors in this study aim to explore patients' perceptions on endoscopic transsphenoidal surgery.Using qualitative research methodology, two semi-structured interviews were conducted with 30 participants who were adults aged18 undergoing endoscopic transsphenoidal surgery for the resection of a pituitary tumour between December 2008 and June 2011. The interviews were audiotaped and transcribed. The resulting data was analyzed using a modified thematic analysis.Seven overarching themes were identified: (1) Patients had a positive surgical experience; (2) patients were satisfied with the results of the procedure; (3) patients were initially surprised that neurosurgery could be performed endonasally; (4) patients expected a cure and to feel better after the surgery; (5) many patients feared that something might go wrong during the surgery; (6) patients were psychologically prepared for the surgery; (7) most patients reported receiving adequate pre-op and post-op information.This is the first qualitative study reporting on patients' perceptions before and after an endoscopic endonasal transsphenoidal pituitary surgery, which is increasingly used as a standard surgical approach for patients with pituitary tumours. Patients report a positive perception and general satisfaction with the endoscopic transsphenoidal surgical experience. However, there is still room for improvement in post-surgical care. Overall, patients' perceptions can help improve the delivery of comprehensive care to future patients undergoing pituitary tumour surgery.

An American Academy of Neurology practice parameter recommends that long-term prophylactic anti-epileptic drugs (AED) should not be routine in patients with newly diagnosed brain tumors. However, prospective multi-center North American data shows that most newly diagnosed glioma patients receive prophylactic AED. We examined our own peri-operative AED practice patterns in newly-diagnosed patients with malignant glioma to determine if we deviate from published guidelines. A retrospective chart review was performed in adult patients with newly diagnosed malignant gliomas undergoing surgery in southern Alberta between January 2003 and December 2005. Demographic information, AED use, seizure incidence, adverse effects, tumor size, and tumor location were recorded. Of 164 eligible patients, 54 (33%) presented with seizures and all received AED. Prophylactic AED were given to 44 patients (27%). Peri-operative seizures (within 1 week) occurred in two patients without (3%) and no patients with seizure prophylaxis. Adverse AED reactions and adverse effects attributable to seizures were both rare. Prophylactic AED were continued >1 week post-op in 30 patients (18%). Patients receiving prophylactic AED were more likely to have had tumors involving the temporal lobe than those who did not (50 vs. 20%; P < 0.01). Patients receiving peri-operative AED prophylaxis were common, had a trend to reduced peri-operative seizures, and had few adverse effects. However, most of these patients were maintained on prophylactic AED continued beyond the first peri-operative week, contradicting published guidelines. Increased awareness of practice guidelines may help modify AED prescription patterns in malignant glioma patients.

Background Bone invasive skull base meningiomas are a subset of meningiomas that present a unique clinical challenge due to brain and neural structure involvement and limitations in complete surgical resection, resulting in higher recurrence and need for repeat surgery. To date, the pathogenesis of meningioma bone invasion has not been investigated. We investigated immunoexpression of proteins implicated in bone invasion in other tumor types to establish their involvement in meningioma bone invasion. Methods Retrospective review of our database identified bone invasive meningiomas operated on at our institution over the past 20 years. Using high-throughput tissue microarray (TMA), we established the expression profile of osteopontin (OPN), matrix metalloproteinase-2 (MMP2), and integrin beta-1 (ITGB1). Differential expression in tumor cell and vasculature was evaluated and comparisons were made between meningioma anatomical locations. Results MMP2, OPN, and ITGB1 immunoreactivity was cytoplasmic in tumor and/or endothelial cells. Noninvasive transbasal meningiomas exhibited higher vascular endothelial cell MMP2 immunoexpression compared to invasive meningiomas. We found higher expression levels of OPN and ITGB1 in bone invasive transbasal compared to noninvasive meningiomas. Strong vascular ITGB1 expression extending from the endothelium through the media and into the adventitia was found in a subset of meningiomas. Conclusions We have demonstrated that key proteins are differentially expressed in bone invasive meningiomas and that the anatomical location of bone invasion is a key determinant of expression pattern of MMP1, OPN, and ITGB1. This data provides initial insights into the pathophysiology of bone invasion in meningiomas and identifies factors that can be pursued as potential therapeutic targets.