R. Michael Scott
Boston Children's Hospital
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Stroke | 2008
E. Steve Roach; Meredith R. Golomb; Robert J. Adams; José Biller; Stephen R. Daniels; Gabrielle deVeber; Donna M. Ferriero; Blaise V. Jones; Fenella J. Kirkham; R. Michael Scott; Edward R. Smith
PURPOSE The purpose of this statement is to review the literature on childhood stroke and to provide recommendations for optimal diagnosis and treatment. This statement is intended for physicians who are responsible for diagnosing and treating infants, children, and adolescents with cerebrovascular disease. METHODS The Writing Group members were appointed by the American Heart Association Stroke Councils Scientific Statement Oversight Committee. The panel included members with several different areas of expertise. Each of the panels recommendations was weighted by applying the American Heart Association Stroke Councils Levels of Evidence grading algorithm. After being reviewed by panel members, the manuscript was reviewed by 4 expert peer reviewers and by members of the Stroke Council Leadership Committee and was approved by the American Heart Association Science Advisory and Coordinating Committee. We anticipate that this statement will need to be updated in 4 years. RESULTS Evidence-based recommendations are provided for the prevention of ischemic stroke caused by sickle cell disease, moyamoya disease, cervicocephalic arterial dissection, and cardiogenic embolism. Recommendations on the evaluation and management of hemorrhagic stroke also are provided. Protocols for dosing of heparin and warfarin in children are suggested. Also included are recommendations on the evaluation and management of perinatal stroke and cerebral sinovenous thrombosis in children.
The New England Journal of Medicine | 2009
R. Michael Scott; Edward R. Smith
Moyamoya disease is a cerebrovascular condition predisposing affected patients to stroke in association with progressive stenosis of the intracranial internal carotid arteries and their proximal branches. Patients with characteristic moyamoya vasculopathy plus associated conditions are categorized as having moyamoya syndrome. This review describes the demographic characteristics, pathogenesis, evaluation, and treatment of moyamoya disease and syndrome.
International Journal of Radiation Oncology Biology Physics | 1993
Stella Hetelekidis; Patrick D. Barnes; May L. Tao; Edwin G. Fischer; Lindsey Schneider; R. Michael Scott; Nancy J. Tarbell
PURPOSE The management of craniopharyngioma is controversial, and surgery alone is frequently advocated. The purpose of this study was to assess the long-term impact of various treatments in childhood craniopharyngioma. METHODS AND MATERIALS Sixty-one children < or = 21 years of age at diagnosis were treated for craniopharyngioma at Childrens Hospital and the Joint Center for Radiation Therapy in Boston from 1970 to 1990. The median age was 7.5 years (range 10 months-21 years). There were 33 females and 28 males. The median follow-up was 10 years (range 2-20.5 years). Neuroimaging was available for detailed review in 53. Nine children were treated with radiotherapy alone, 15 were treated with surgery alone, and 37 were treated with both surgery and radiotherapy. All patients in the radiotherapy and surgery plus radiotherapy groups were treated with megavoltage radiation with a median dose of 5464 cGy. RESULTS All nine of the children treated with radiation therapy alone are alive; none have recurred. Nine of the 15 children treated with surgery alone have recurred (p = 0.007 Fisher exact test). Two are alive with disease, and seven are alive without disease after treatment at relapse with radiation therapy, surgery, or both. Seven of the 37 patients treated with surgery plus radiotherapy have recurred. Three of the seven patients are dead of disease, three patients are alive with disease, and one patient is alive without disease after further treatment. The 10-year actuarial overall survival was 91% for all patients. The 10-year actuarial freedom from progression for the surgery group was 31% compared with 100% for patients treated with radiation therapy only (log rank p = 0.01), and 86% for patients treated with surgery plus radiotherapy at diagnosis (p = 0.001). There were two treatment related deaths, both in the surgery plus radiotherapy group. A higher incidence of visual loss and diabetes insipidus was associated with the use of aggressive surgery. The size of the tumor at presentation correlated with an increased risk of recurrence; 5 of 6 patients with tumors > or = 5 cm experienced recurrences while only 6 of 30 recurred when the tumor was < 5 cm. CONCLUSIONS Overall survival in childhood craniopharyngioma is excellent. However, patients treated with surgery alone have a significantly worse freedom from progression when compared to patients treated with surgery and radiation therapy or radiation therapy alone.
Nature Genetics | 2014
Priscilla K. Brastianos; Amaro Taylor-Weiner; Peter Manley; Robert T. Jones; Dora Dias-Santagata; Aaron R. Thorner; Michael S. Lawrence; Fausto J. Rodriguez; Lindsay A. Bernardo; Laura Schubert; Ashwini Sunkavalli; Nick Shillingford; Monica L. Calicchio; Hart G.W. Lidov; Hala Taha; Maria Martinez-Lage; Mariarita Santi; Phillip B. Storm; John Y. K. Lee; James N. Palmer; Nithin D. Adappa; R. Michael Scott; Ian F. Dunn; Edward R. Laws; Chip Stewart; Keith L. Ligon; Mai P. Hoang; Paul Van Hummelen; William C. Hahn; David N. Louis
Craniopharyngiomas are epithelial tumors that typically arise in the suprasellar region of the brain. Patients experience substantial clinical sequelae from both extension of the tumors and therapeutic interventions that damage the optic chiasm, the pituitary stalk and the hypothalamic area. Using whole-exome sequencing, we identified mutations in CTNNB1 (β-catenin) in nearly all adamantinomatous craniopharyngiomas examined (11/12, 92%) and recurrent mutations in BRAF (resulting in p.Val600Glu) in all papillary craniopharyngiomas (3/3, 100%). Targeted genotyping revealed BRAF p.Val600Glu in 95% of papillary craniopharyngiomas (36 of 39 tumors) and mutation of CTNNB1 in 96% of adamantinomatous craniopharyngiomas (51 of 53 tumors). The CTNNB1 and BRAF mutations were clonal in each tumor subtype, and we detected no other recurrent mutations or genomic aberrations in either subtype. Adamantinomatous and papillary craniopharyngiomas harbor mutations that are mutually exclusive and clonal. These findings have important implications for the diagnosis and treatment of these neoplasms.
Clinical Cancer Research | 2008
Edward R. Smith; David Zurakowski; Ali Saad; R. Michael Scott; Marsha A. Moses
Purpose: A major difficulty in treating brain tumors is the lack of effective methods of identifying novel or recurrent disease. In this study, we have evaluated the efficacy of urinary matrix metalloproteinases (MMP) as diagnostic biomarkers for brain tumors. Experimental Design: Urine, cerebrospinal fluid, and tissue specimens were collected from patients with brain tumors. Zymography, ELISA, and immunohistochemistry were used to characterize the presence of MMP-2, MMP-9, MMP-9/neutrophil gelatinase–associated lipocalin (NGAL), and vascular endothelial growth factor (VEGF). Results were compared between age- and sex-matched controls and subjected to univariate and multivariate statistical analyses. Results: Evaluation of a specific panel of urinary biomarkers by ELISA showed significant elevations of MMP-2, MMP-9, MMP-9/NGAL, and VEGF (all P < 0.001) in samples from brain tumor patients compared with controls. Multiplexing MMP-2 and VEGF provided superior accuracy compared with any other combination or individual biomarker. Receiver-operating characteristics curves for MMP-2 and VEGF showed excellent discrimination. Immunohistochemistry identified these same proteins in the source tumor tissue. A subset of patients with longitudinal follow-up revealed subsequent clearing of biomarkers after tumor resection. Conclusion: We report, for the first time, the identification of a panel of urinary biomarkers that predicts the presence of brain tumors. These biomarkers correlate with presence of disease, decrease with treatment, and can be tracked from source tissue to urine. These data support the hypothesis that urinary MMPs and associated proteins are useful predictors of the presence of brain tumors and may provide a basis for a novel, noninvasive method to identify new brain tumors and monitor known tumors after treatment.
International Journal of Radiation Oncology Biology Physics | 1997
Patricia Harrigan Hardenbergh; Jeffrey A. Golden; Amy L. Billet; R. Michael Scott; Dennis C. Shrieve; Barbara Silver; Jay S. Loeffler; Nancy J. Tarbell
PURPOSE To determine the optimal dose and treatment outcome of patients treated with radiation for intracranial germinoma. METHODS AND MATERIALS Between 1975 and 1995, 40 patients with the diagnosis of intracranial germinoma were treated with radiation (RT) to the central nervous system. All patients received whole-brain (WB) RT (median dose: 32.4 Gy, range: 15-44.37 Gy) and a boost to the tumor volume (median total tumor volume dose: 52 Gy, range: 45-59.5 Gy). Thirty patients received RT to the spine (median dose: 26 Gy, range: 18.75-37.5 Gy). Four patients were treated with cisplatin-based chemotherapy and WB RT with a boost to the tumor volume (dose range: 51-54 Gy). A low-dose RT only group was defined as < or = 25.5 Gy to the WB (9 patients); < 50 Gy to the primary site (14 patients); and < 22 Gy to the spine (9 patients). Seventeen tumors were biopsy-proven germinoma, and 17 patients presented with multiple midline germinomas (MMG). Among 26 patients who had tumor markers measured, 27% had elevation of beta-human chorionic gonadotropin and by definition, no patient had an elevation of AFP. Twenty-four percent of 26 patients who had spine imaging or cerebral spinal fluid cytology had evidence of tumor seeding at diagnosis. The male to female ratio was 1.9:1. Median age at diagnosis was 14 years for male patients and 9.5 years for female patients (p = 0.02), (overall age ranges: 0.5-31 years). Median follow-up was 62 months (range: 3-226 months). Late effects of 29 patients with follow-up of > or = 20 months and adequate documentation in their medical records were analyzed. RESULTS The 5-year actuarial rate of disease-free survival (DFS) and overall survival (OS) for biopsy-proven germinomas and presumed germinomas was 97%. No patient died of germinoma. There were no local failures regardless of the dose of RT, elevation of HCG tumor marker, or CSF dissemination at presentation. At presentation 22 patients had evidence of at least one endocrine abnormality. At follow-up there were no new patients diagnosed with an endocrine abnormality; however, 13 out of 22 patients had an increase in the number of endocrine deficiencies requiring hormone replacement. At presentation, 14 patients showed evidence of growth retardation. At follow-up there were no new cases of growth failure in the remaining patients. CONCLUSIONS Germinomas are highly curable with RT alone. Lower doses of RT to the craniospinal axis without chemotherapy appear to produce equally effective DFS and OS as do higher doses of RT or combination chemotherapy and RT. Craniospinal RT may be indicated for patients with MMG or patients with evidence of spinal seeding. Long-term effects of growth retardation, and other endocrine deficiencies appear to be correlated with disease at presentation rather than solely with treatment.
International Journal of Radiation Oncology Biology Physics | 1994
Susan F. Dunbar; Nancy J. Tarbell; Hanne M. Kooy; Eben Alexander; Peter McL. Black; Patrick D. Barnes; Liliana Goumnerova; R. Michael Scott; Scott L. Pomeroy; Beverly La Vally; Stephen E. Sallan; Jay S. Loeffler
PURPOSE Stereotactic radiotherapy is a new modality that combines the accurate focal dose delivery of stereotactic radiosurgery with the biological advantages of conventional radiotherapy (1.8-2.0 Gy/day using 25-30 fractions). The modality requires sophisticated treatment planning, dedicated high-energy linear accelerator, and relocatable immobilization devices. We report here our early experience using stereotactic radiotherapy for intracranial neoplasms. METHODS AND MATERIALS Between June 1992 and September 1993, we treated 82 patients with central nervous system lesions using stereotactic radiotherapy, delivered from a dedicated 6 MV stereotactic linear accelerator. A head fixation frame provided daily relocatable setup using a dental plate for all patients over 8 years of age. A modified head frame, which does not require a mouthpiece, was used for children requiring anesthesia. The patients ranged in age from 9 months to 76 years. Thirty-three patients were children less than 21 years of age. Selection criteria for the protocol included: (a) focal, small (< 5 cm) radiographically distinct lesions known to be radiocurable (pituitary adenoma, craniopharyngioma, meningioma, acoustic neuroma, pilocytic astrocytoma, retinoblastoma), and (b) lesions located in regions not amenable to surgery or radiosurgery such as the brain stem or chiasm. Standard fractionation and conventional doses were delivered. Patients with low-grade astrocytoma, oligodendroglioma, or ependymoma were treated using a dose escalation regime consisting of conventional doses plus a 10% increase. RESULTS Although follow-up is 16 months (range 3-16 months), posttreatment radiographic studies in 77 patients have been consistent with changes similar to those found after conventional radiation therapy. To date, reduction of up to 50% of the original volume has been noted in 19 out of 77 patients, and 4 patients had a complete response, 2 with dysgerminoma, and 1 each with astrocytoma and retinoblastoma. In 56 patients disease was either stable or the follow-up was too short for evaluation. While the follow-up is relatively short, there have been no in-field or marginal recurrences. The only unexpected radiographic findings were in three patients with pilocytic astrocytomas, who developed asymptomatic edema in the treatment volume. Accuracy in daily fractionation was excellent. In over 2000 patient setups with 41,000 scalp measurements, reproducibility was found to be within 0.41 mm (median) of baseline readings, allowing for precise immobilization throughout the treatment course. The treatment in all cases was well tolerated with minimal acute effects. Our stereotactic radiotherapy facility can provide fractionated therapy for 10-12 patients a day efficiently and accurately. CONCLUSIONS The treatment and relocatable stereotactic head frames were well tolerated with minimal acute effects. No long-term sequelae have been noted, although the observation period is short. To fully define the role of stereotactic radiotherapy, we are conducting prospective studies to evaluate neurocognitive and neuroendocrine effects. We expect that this innovative approach will make a significant impact on the treatment of intracranial neoplasms, particularly in children.
Pediatrics | 2005
Andrew Jea; Edward R. Smith; Richard L. Robertson; R. Michael Scott
Objectives. This study was undertaken to describe the clinical, radiologic, and angiographic features of moyamoya syndrome in a surgical series of children and adults with Down syndrome. We wished to define the features of moyamoya syndrome associated with Down syndrome and to determine the results of surgical revascularization among these patients at early and late follow-up times. Methods. We reviewed the clinical, radiologic, and angiographic records of all patients with moyamoya syndrome associated with Down syndrome, as a subset of a previously reported, consecutive series of patients who underwent cerebral revascularization surgery with a standardized surgical procedure, pial synangiosis, between January 1, 1985, and June 30, 2004. Results. Of 181 patients with moyamoya syndrome from the initial series who were treated surgically during the study period, 16 patients had Down syndrome (10 female patients and 6 male patients). The average age at onset was 9.3 years (range: 1–29 years); the average age at the time of surgery was 9.8 years (range: 2–29 years). Although the presenting symptoms were transient ischemic attacks for 10 patients and strokes for 6 patients, computed tomographic and/or MRI scans demonstrated bilateral infarctions for 9 patients and unilateral infarctions for 6, with only 1 patient having no imaging evidence of a previous stroke. No cases presented with intracerebral hemorrhage. Preoperative angiography showed the presence of bilateral moyamoya syndrome changes for all patients, including posterior circulation involvement for 8 patients. Surgical treatment included pial synangiosis for all patients, although 1 patient underwent a superficial temporal artery-middle cerebral artery bypass in the contralateral hemisphere. Surgical complications included symptomatic subdural hematomas requiring evacuation, at 48 days and 54 days postoperatively (2 cases), seizures (2 cases), and strokes within 30 days after surgery, at 1 day and 7 days postoperatively (2 cases). Late clinical and radiologic follow-up data (average: 67.6 months; range: 6–146 months) demonstrated no worsening in neurologic status for any patient except for 1 patient who developed a seizure disorder with associated chronic hypocalcemia; she was totally dependent at the 10-year follow-up evaluation, despite no evidence of new infarction since her surgery. There was no clinical or radiologic evidence of new infarction for any patient in late follow-up evaluations. Postoperative angiography, conducted 1 year after surgery for 11 patients, revealed radiologic evidence of good to excellent cerebral revascularization in 85% of the surgically treated hemispheres. Patients were maintained on lifetime aspirin therapy. Conclusions. The clinical, radiologic, and angiographic features of moyamoya syndrome associated with Down syndrome seem comparable to those of primary moyamoya disease. Cerebral revascularization surgery with the pial synangiosis technique seems to confer long-lasting protection against additional strokes in this patient population. The presence of moyamoya syndrome should be considered in the evaluation of patients with Down syndrome who present with transient ischemic attack-like symptoms.
Cancer | 1991
Nancy J. Tarbell; Jay S. Loeffler; Barbara Silver; Elizabeth A. Lynch; Beverly Lavally; William J. Kupsky; R. Michael Scott; Stephen E. Sallan
The authors reviewed 89 patients treated for cerebellar medulloblastoma between 1970 and 1989 to determine the impact of changing treatment (high‐dose posterior fossa radiation therapy and chemotherapy) on the pattern of failure in medulloblastoma. Between 1970 and 1983, 50 patients (median follow‐up, 110 months) were treated with surgery and postoperative craniospinal irradiation (CSI). Nineteen of the 50 (38%) recurred in the central nervous system (CNS). Isolated systemic (bone) metastases occurred in six. The median time to the development of bone metastases was 12 months. Since 1984, 39 patients (median follow‐up, 27 months) were treated with preradiation chemotherapy consisting of cisplatin and vincristine for 9 weeks before initiation of CSI. Nine of the 39 (23%) patients recurred in the CNS. There were no systemic failures in this cohort. The actuarial 5‐year disease‐free survival was 55 ± 7% for the earlier cohort and 72 ± 8% for the later cohort (P equals 0.3). Posterior fossa recurrence was associated with radiation therapy to this area. The cumulative incidence of posterior fossa relapse was 50 ± 13% in patients who received less than 5300 cGy and 18 ± 7% in those who received 5300 cGy or more (P equals 0.005). All six bone relapses were in patients treated with CSI alone and 5300 cGy or more to the posterior fossa for a 5‐year cumulative incidence of bone metastases of 18 ± 7% compared with 0% for patients treated with 5300 cGy or more and chemotherapy (P equals 0.03). The authors concluded that high‐dose radiation therapy has altered the pattern of relapse with an increase in systemic recurrence after radiation therapy alone that is now equivalent to the risk of recurrence in the posterior fossa. Chemotherapy may be indicated in an attempt to decrease this high risk of systemic metastases.
Neurosurgery | 2001
Sarah C. Carpentieri; Deborah P. Waber; R. Michael Scott; Liliana Goumnerova; Mark W. Kieran; Laurie E. Cohen; Francine Kim; Amy L. Billett; Nancy J. Tarbell; Scott L. Pomeroy
OBJECTIVETo describe neuropsychological functioning (with a specific focus on cognition and memory) after surgical treatment of craniopharyngiomas. METHODSSixteen patients who were between 6 and 15 years of age at the time of surgery comprised the sample. Each child had been treated for a craniopharyngioma with surgery only, on Dana-Farber Cancer Institute Protocol 92-077. RESULTSThe overall level of cognitive functioning was well within the average range, with both language and visuospatial functioning being generally intact; however, specific memory problems, in both the language and visuospatial domains, were evident. CONCLUSIONAlthough general cognitive functioning was intact after the surgical treatment of craniopharyngiomas, difficulties in the retrieval of learned information were observed. Neuropsychological assessments, with a focus on memory recall, should be a component of the medical management plan for each child.