Resection of parietal lobe gliomas： incidence and evolution of neurological deficits in 28 consecutive patients correlated to the location and morphological characteristics of the tumor

OBJECT： The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS： Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance （MR） images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients （64%）; had a mean diameter of 39 mm （range 14-69 mm）; were isolated to the superior parietal lobule in six patients （21%） and to the inferior parietal lobule in eight patients （29%）; and involved both lobules in 14 patients （50%）. Gross-total resection, documented by MR imaging, was achieved in 24 patients （86%）. Postoperatively, nine patients （32%） experienced new neurological deficits, whereas seven （25%） had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level （association） parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS： Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits （for example, a visual field loss or cortical sensory syndrome） occurred in patients regardless of hemispheric dominance.     

Functional connectivity of the default mode,dorsal attention and fronto-parietal executive control networks in glial tumor patients

Journal of Neuro-Oncology - Resting state functional magnetic resonance imaging (rsfMRI) is an emerging tool to explore the functional connectivity of different brain regions. We aimed to assess...     

Challenging the current paradigm of melanoma progression: brain metastasis as isolated first visceral site

Melanoma brain metastasis that develops as the isolated first visceral site challenges the current paradigm of tumor progression in which brain metastasis is regarded as the final stage. Here we test the hypothesis that melanoma patients who develop brain metastasis as the isolated first visceral site have distinct clinicopathological features at the time of primary melanoma diagnosis. Cutaneous melanoma patients enrolled in 2 prospectively collected databases were studied (Cohort 1: 1972-1982, Cohort 2: 2002-2009). Patients who developed brain metastasis as isolated first visceral site were compared with (1) all other patients, (2) patients who developed visceral metastasis: extracranial only or extracranial and brain, and (3) patients who progressed to other isolated visceral sites first. Two hundred seven of 2280 (9.1%) patients developed brain metastasis (median follow-up, 5.2 y). Seventy-four of 207 (35.7%) brain metastasis patients progressed to brain metastasis as the isolated first visceral site. These patients presented with primaries that were thinner and had no mitosis compared with all other visceral metastasis patients (Fisher's combined P = .02, .05, respectively), and there was a significant difference in American Joint Committee on Cancer stage distribution at initial melanoma diagnosis (combined P = .02). Post-visceral metastasis survival, however, was shorter in patients with brain metastasis as isolated first visceral site than in patients with visceral metastasis: extracranial and brain (combined P = .03). Brain metastasis as isolated first visceral site is a distinct clinicopathological entity. Studies are needed to better understand the biological factors driving this phenotype at the time of primary melanoma diagnosis and to determine its clinical implications.     

A comparison of survival rates for treatment of melanoma metastatic to the brain

Introduction: A retrospective review of 91 patients with brain metastases from malignant melanoma treated at New York University Medical Center between 1989-1999. Overall survival was the outcome evaluated. Methods: Charts of 91 patients having malignant melanoma with brain metastases were reviewed. Cases were stratified according to therapy: surgical excision, surgical excision plus whole brain radiation therapy, gamma knife stereotactic radiosurgery, gamma knife stereotactic radiosurgery plus whole brain radiation therapy, and whole brain radiation therapy alone. Patients treated with gamma knife stereotactic radiosurgery plus radiation therapy were combined with patients treated with surgical excision plus radiation therapy and compared to those treated with radiation therapy alone. Prognostic characteristics of the two groups were compared and survival curves were generated using the Kaplan-Meier method. The Cox proportional hazards model was used to control for prognostic factors that differed between the groups. Results: Patients treated with gamma knife stereotactic radiosurgery or surgical excision plus radiation therapy were younger, less likely to present with symptoms, and presented with fewer metastases to the brain than patients treated with radiation therapy alone. A survival benefit of 7.3 months (p = 0.05) was found to be associated with gamma knife radiosurgery or surgical excision plus radiation therapy over radiation therapy alone after controlling for differences in age, number of brain lesions, and presence of symptoms. Discussion: This retrospective study of 91 patients treated for melanoma metastases to the brain attempts to examine the effectiveness of different treatments in prolonging survival. Our results suggest that surgical excision or stereotactic radiosurgery with gamma knife in addition to radiation therapy may be more effective than radiation alone at prolonging survival for patients with a limited number of brain lesions. Conclusion: Survival of patients with melanoma metastases to the brain may be prolonged by treatment with gamma knife stereotactic radiosurgery or surgical excision plus whole brain radiation therapy.     

Importance of MR technique for stereotactic radiosurgery

We investigated how frequently the imaging procedure we use immediately prior to radiosurgery--triple-dose gadolinium-enhanced MR performed with the patient immobilized in a nonrelocatable head frame and 1-mm-thick MPRAGE (magnetization-prepared rapid gradient echo) images (SRS3xGado)-identifies previously unrecognized cerebral metastases in patients initially imaged by conventional MR with single-dose gadolinium (1xGado). Between July 1998 and July 2000, the diagnoses established for 47 patients who underwent radio-surgical procedures for treatment of cerebral metastases at The Gamma Knife Center of New York University were based initially on the 1xGado protocol. In July 1998, we began using SRS3xGado as our routine imaging protocol in preparation for targeting lesions for radio-surgery, using triple-dose gadolinium and acquisition of contiguous 1-mm Tl-weighted axial images. Because our SRS3xGado scans sometimes unexpectedly revealed additional metastases, we sought to learn how frequently the initial 1xGado scans would underestimate the number of metastases. We therefore reviewed the number of brain metastases identified on the SRS3xGado studies and compared the results to the number found by the 1xGado protocol, which had initially identified the brain metastases. Additional metastases, ranging from 1 to 23 lesions per patient, were identified on the SRS3xGado scan in 23 of 47 patients (49%). In 57% of the 23 patients, only one additional lesion was identified. The mean time interval between the 1xGado and the SRS3xGado scans was 20.6 days (range, 4-83 days), and the number of additional lesions detected and the time interval between two scans were negatively correlated (-0.11). The number of lesions detected on the SRS3xGado was associated only with the number of lesions on the 1xGado and not with any other patient or tumor pretreatment characteristics such as age, gender, largest tumor volume on the 1xGado, or number of days between the 1xGado and the SRS3xGado or prior surgery. The identification of additional lesions with SRS3xGado MR may have implications for patients who are treated with stereotactic radiosurgery alone (without whole-brain irradiation) with single-dose gadolinium imaging, in that unidentified lesions may go untreated. As a result of these findings we continue to use and advocate SRS3xGado scans for radiosurgery.     

Glial neoplasms: dynamic contrast-enhanced T2*-weighted MR imaging.

PURPOSE: To evaluate the role of T2*-weighted echo-planar perfusion imaging by using a first-pass gadopentetate dimeglumine technique to determine the association of magnetic resonance (MR) imaging-derived cerebral blood volume (CBV) maps with histopathologic grading of astrocytomas and to improve the accuracy of targeting of stereotactic biopsy. MATERIALS AND METHODS: MR imaging was performed in 29 patients by using a first-pass gadopentetate dimeglumine T2*-weighted echo-planar perfusion sequence followed by conventional imaging. The perfusion data were processed to obtain a color map of relative regional CBV. This information formed the basis for targeting the stereotactic biopsy. Relative CBV values were computed with a nondiffusible tracer model. The relative CBV of lesions was expressed as a percentage of the relative CBV of normal white matter. The maximum relative CBV of each lesion was correlated with the histopathologic grading of astrocytomas obtained from samples from stereotactic biopsy or volumetric resection. RESULTS: The maximum relative CBV in high-grade astrocytomas (n = 26) varied from 1.73 to 13.7, with a mean of 5.07 +/- 2.79 (+/- SD), and in the low-grade cohort (n = 3) varied from 0.92 to 2.19, with a mean of 1.44 +/- 0.68. This difference in relative CBV was statistically significant (P < .001; Student t test). CONCLUSION: Echo-planar perfusion imaging is useful in the preoperative assessment of tumor grade and in providing diagnostic information not available with conventional MR imaging. The areas of perfusion abnormality are invaluable in the precise targeting of the stereotactic biopsy.